19-0885; Rev 0; 8/07
KIT
ATION
EVALU
E
L
B
AVAILA
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
The MAX8671X integrated power-management IC
(PMIC) is ideal for use in portable media players and
other handheld devices. In addition to five regulated
output voltages, the MAX8671X integrates a 1-cell lithium ion (Li+) or lithium polymer (Li-Poly) charger and
Smart Power Selector™ with dual (AC-to-DC adapter
and USB) power inputs. The dual-input Smart Power
Selector supports end products with dual or single
power connectors. All power switches for charging and
switching the system load between battery and external
power are included on-chip. No external MOSFETs are
required.
Maxim’s Smart Power Selector makes the best use of
limited USB or AC-to-DC adapter power. Battery
charge current and input current limit are independently set. Input power not used by the system charges the
battery. Charge current and DC current limit are programmable up to 1A while USB input current can be set
to 100mA or 500mA. Automatic input selection switches
the system load from battery to external power. Other
features include overvoltage protection, charge status
and fault outputs, power-OK monitors, charge timer,
and battery thermistor monitor. In addition, on-chip
thermal limiting reduces battery charge rate to prevent
charger overheating.
The MAX8671X offers adjustable voltages for all outputs. Similar parts with factory-preset output voltages
are also available (contact factory for availability).
Features
♦ 16V-Tolerant USB and DC Inputs
♦ Automatically Powers from External Power or
Battery
♦ Operates with No Battery Present
♦ Single-Cell Li+/Li-Poly Charger
♦ Three 2MHz Step-Down Regulators
Up to 96% Efficiency
♦ Two Low IQ Linear Regulators
♦ Output Power-Up Sequencing
♦ Thermal-Overload Protection
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX8671XETL+ -40°C to +85°C
40 Thin QFN-EP*
5mm x 5mm
PKG
CODE
T4055-1
+Denotes a lead-free package.
*EP = Exposed paddle.
Simplified Applications Circuit
AC-TO-DC
ADAPTER
Applications
Portable Audio Players
USB
GPS Portable Navigators
ON
OFF
DC
MAX8671X
SYS
USB
+
Li+/LiPo
BATTERY
EN
PWM
OUT1
OUT1
1V TO VSYS
425mA
PEN1
OUT2
OUT2
1V TO VSYS
425mA
OUT3
OUT3
1V TO VSYS
425mA
PEN2
USUS
CEN
μP
OUT4
OUT4
0.6V TO VSYS
180mA
OUT5
OUT5
0.6V TO VSYS
180mA
CST1
CST2
DOK
UOK
Smart Power Selector is a trademark of Maxim Integrated
Products, Inc.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim's website at www.maxim-ic.com.
1
MAX8671X
General Description
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Table of Contents
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Simplified Applications Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Typical Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Smart Power Selector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
System Load Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
USB Power Input (USB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
USB Power-OK Output (UOK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
USB Suspend (USUS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
DC Power Input (DC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
DC Power-OK Output (DOK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Battery Charger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Battery Regulation Voltage (BVSET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Charge Enable Input (CEN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Charge Status Outputs (CST1, CST2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Charge Timer (CT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Setting The Charger Currents (CISET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Step-Down Converters (REG1, REG2, REG3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
PWM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Step-Down Dropout and Minimum Duty Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Step-Down Input Capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Step-Down Output Capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Step-Down Inductor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Step-Down Converter Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Linear Regulators (REG4, REG5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
VL Linear Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Enable/Disable (EN) and Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Soft-Start/Inrush Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Active Discharge in Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Undervoltage and Overvoltage Lockout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
USB/DC UVLO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
USB/DC OVLO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
SYS UVLO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
REG4/REG5 UVLO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Thermal Limiting and Overload Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Smart Power Selector Thermal-Overload Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Regulator Thermal-Overload Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Battery Charger Thermistor Input (THM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
PCB Layout and Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Package Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Chip Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
2
_______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Tables
Table 1. Input Limiter Control Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 2. DC Current Limit for Standard Values of RDISET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 3. Charge Status Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Table 4. Charge Times vs. CCT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Table 5. Ideal Charge Currents vs. Charge Setting Resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Table 6. Suggested Inductors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Table 7. 5mm x 5mm x 0.8mm Thin QFN Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Table 8. Trip Temperatures for Different Thermistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Figures
Figure 1. MAX8671X Typical Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 2. Functional Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 3. USB Power-OK Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Figure 4. Programming DC Current Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 5. DC Power-OK Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 6. Li+/Li-Poly Charge Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Figure 7. Charger State Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Figure 8. Programming Charge Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 9. Monitoring the Battery Charge Current with the Voltage from CISET to AGND . . . . . . . . . . . . . . . . . . 32
Figure 10. Step-Down Converter Maximum Output Current Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 11. Enable/Disable Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Figure 12. Enable and Disable Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Figure 13. REG5 Disable Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Figure 14. Thermistor Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Figure 15. Package Marking Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
_______________________________________________________________________________________
3
MAX8671X
Table of Contents (continued)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
ABSOLUTE MAXIMUM RATINGS
USB, DC, PEN1 to AGND.......................................-0.3V to +16V
SYS, BAT, PV1, PV2, PV3 to AGND..........................-0.3V to +6V
PG1, PG2, PG3, AGND .........................................-0.3V to +0.3V
PV1, PV2, PV3 to SYS............................................-0.3V to +0.3V
VL to AGND ...........................................................-0.3V to +4.0V
CISET, DISET, BVSET, CT, THM to AGND..-0.3V to (VVL + 0.3V)
PV4, PV5, BP, FB1, FB2, FB3 to AGND ....-0.3V to (VSYS + 0.3V)
PEN2, USUS, CEN, EN, PWM to AGND ..................-0.3V to +6V
CST1, CST2, DOK, UOK to AGND ...........................-0.3V to +6V
OUT4, FB4 to AGND .................................-0.3V to (VPV4 + 0.3V)
OUT5, FB5 to AGND .................................-0.3V to (VPV5 + 0.3V)
LX1, LX2, LX3 Continuous RMS Current (Note 1).................1.5A
BAT Continuous Current .......................................................1.5A
SYS Continuous Current .......................................................1.5A
Continuous Power Dissipation (TA = +70°C)
40-Pin, 5mm x 5mm, Thin QFN (derate 35.7mW/°C
above +70°C)..............................................................2857mW
Operating Junction Temperature.....................................+150°C
Storage Junction Temperature Range ..............-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1: LX_ has internal clamp diodes to PG_ and PV_. Applications that forward bias these diodes must take care not to exceed
the package power dissipation limits.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC POWER INPUT (VDC = 5.0V, EN = low)
DC Voltage Range
SYS Regulation Voltage
VDC
VSYS_REG
Operating voltage
4.1
6.6
Withstand voltage
0
14
V
VDC = 6V, USUS = low, CEN = high, system
current is less than the input current limit
5.2
5.3
5.4
V
DC Undervoltage Threshold
VDCL
VDC rising, 500mV typical hysteresis
3.95
4.00
4.05
V
DC Overvoltage Threshold
VDCH
VDC rising, 400mV typical hysteresis
PEN1 = low,
VDC = 6V, VSYS = 5V PEN2 = low,
USUS = low
USB unconnected,
CEN = low,
PEN1 = low,
TA = +25°C,
PEN2 = high,
VL = no load
USUS = low
(Note 3)
PEN1 = high,
RDISET = 3kΩ
6.8
6.9
7.0
V
90
95
100
450
475
500
950
1000
1050
DC Current Limit
IDCLIM
RDISET Resistance Range
DC Quiescent Current
3
IDCIQ
PEN1 = low, USUS = high
USUS = low, CEN = low;
ISYS = 0mA, IBAT = 0mA, EN = low;
VL no load
6
mA
kΩ
0.11
1.1
USUS = low, CEN = high;
ISYS = 0mA, VEN = 0V, VL no load
mA
0.7
Minimum DC-to-BAT Voltage
Headroom
VDC falling, 200mV hysteresis
0
15
30
mV
Minimum DC-to-SYS Voltage
Headroom
VDC falling, 200mV hysteresis
0
15
30
mV
0.325
0.600
Ω
DC-to-SYS Dropout Resistance
4
RDS
VDC = 5V, ISYS = 400mA, USUS = low
_______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
DC-to-SYS Soft-Start Time
SYMBOL
tSS-D-S
CONDITIONS
MIN
TYP
MAX
UNITS
Starting DC when no USB present
1.0
ms
Starting DC with USB present
35
µs
DC Thermal-Limit Temperature
Die temperature at which current limit is
reduced
+100
°C
DC Thermal-Limit Gain
Amount of input current reduction above
thermal-limit temperature
5
%/°C
USB POWER INPUT (VUSB = 5.0V, EN = low)
USB Voltage Range
VUSB
SYS Regulation Voltage
VSYS_REG
Operating voltage
4.1
6.6
Withstand voltage
0
14
VUSB = 6V, USUS = low, CEN = high,
system current is less than the input current
limit
5.2
5.3
5.4
V
V
USB Undervoltage Threshold
VUSBL
VUSB rising, 500mV hysteresis
3.95
4.0
4.05
V
USB Overvoltage Threshold
VUSBH
VUSB rising, 400mV hysteresis
6.8
6.9
7.0
V
PEN2 = low,
USUS = low
90
95
100
IUSBLIM
VUSB = 6V, VSYS = 5V, DC
unconnected, CEN = low,
TA = +25°C,
IVL = 0A (Note 3)
PEN2 = high,
USUS = low
450
475
500
USB Current Limit
USB Quiescent Current
IUSBIQ
mA
USUS = high
0.11
USUS = low, CEN = low;
ISYS = 0mA, IBAT = 0mA, VL no load
1.1
2.0
USUS = low, CEN = high;
ISYS = 0mA, VL no load
0.7
1.3
mA
Minimum USB-to-BAT Voltage
Headroom
VUSB falling, 200mV hysteresis
0
15
30
mV
Minimum USB-to-SYS Voltage
Headroom
VUSB falling, 200mV hysteresis
0
15
30
mV
0.325
0.600
Ω
USB-to-SYS Dropout Resistance
USB-to-SYS Soft-Start Time
RUS
VUSB = 5V, ISYS = 400mA, USUS = low
tSS-U-S
1.0
ms
USB Thermal-Limit Temperature
Die temperature at which current limit is
reduced
100
°C
USB Thermal-Limit Gain
Amount of input current reduction above
thermal-limit temperature
5
%/°C
SYSTEM (VDC = 5.0V, EN = low)
System Operating Voltage Range
System Undervoltage Threshold
VSYS
VUVLO_SYS SYS falling, 100mV hysteresis
2.6
2.45
2.50
5.5
V
2.55
V
_______________________________________________________________________________________
5
MAX8671X
ELECTRICAL CHARACTERISTICS (continued)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
ELECTRICAL CHARACTERISTICS (continued)
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
BAT-to-SYS Reverse Regulation
Voltage
Quiescent Current
SYMBOL
VBSREG
IPV1 +
IPV2 +
IPV3 +
IPV4 +
IPV5 +
ISYS
CONDITIONS
DC or USB and BAT
are sourcing current
BAT is sourcing
105mA
MIN
TYP
MAX
65
82
115
UNITS
mV
BAT is sourcing
905mA
130
DC and USB unconnected, EN = low,
VBAT = 4V
0
10
VDC = VUSB = 5V, USUS = high,
PEN1 = low, EN = low, VBAT = 4V
0
10
155
285
425
550
180
320
DC and USB unconnected, EN = high,
VBAT = 4V (step-down converters are not in
dropout), PWM = low (Note 4)
DC and USB unconnected, EN = high,
VBAT = 2.8V (at least one step-down
converter is in dropout), PWM = low (Note 4)
VDC = VUSB = 5V, USUS = high, EN = high,
VBAT = 4V, PWM = low (Note 4)
DC and USB unconnected, EN = high,
VBAT = 4.0V, PWM = high
9
µA
mA
BATTERY CHARGER (VDC = 5.0V, EN = low)
BAT-to-SYS On-Resistance
RBS
VUSB = 0V, VBAT = 4.2V, ISYS = 1A
BVSET = VL or
BVSET unconnected
BAT Regulation Voltage
(Figure 6)
VBATREG
BAT Prequalification Threshold
6
4.200
4.221
TA = -40°C to +85°C
4.145
4.200
4.242
VBATPRQ
VCISET
Ω
TA = +25°C
4.073
4.100
4.121
4.047
4.100
4.141
TA = +25°C
4.325
4.350
4.376
TA = -40°C to +85°C
4.297
4.350
4.398
-170
-120
-70
mV
VBAT rising, 180mV hysteresis, Figure 6
2.9
3.0
3.1
V
Guaranteed by BAT fast-charge current
limit
3
15
kΩ
RCISET = 7.5kΩ, IBAT = 267mA, Figure 9
0.9
1.1
V
VBATRCHG (Note 5)
RCISET Resistance Range
CISET Voltage
0.16
4.174
TA = -40°C to +85°C
BVSET = AGND
RBVSET = 49.9kΩ to
AGND
BAT Recharge Threshold
0.08
TA = +25°C
1.0
_______________________________________________________________________________________
V
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
BAT Prequalification Current
Low-power USB charging from the USB
input, DC unconnected, RCISET = 3kΩ,
PEN2 = low, USUS = low
Low-power USB charging from the DC
input, RCISET = 3kΩ, PEN1 = low,
PEN2 = low, USUS = low
High-power USB charging from the USB
input, DC unconnected, RCISET = 3kΩ,
PEN2 = high, USUS = low
High-power USB charging from the DC
input, RCISET = 3kΩ, PEN2 = high,
USUS = low
AC-to-DC adapter charging from the DC
input, RDISET = 3kΩ, RCISET = 15kΩ,
PEN1 = high
AC-to-DC adapter charging from the DC
input, RDISET = 3kΩ, RCISET = 7.5kΩ,
PEN1 = high
AC-to-DC adapter charging from the DC
input, RDISET = 3kΩ, RCISET = 3.74kΩ,
PEN1 = high
VBAT = 2.5V, RCISET = 3.74kΩ
Top-Off Threshold
TA = +25°C, RCISET = 3.74kΩ (Note 6)
BAT Fast-Charge Current Limit
EN = low,
TA = +25°C
BAT Leakage Current
Charger Soft-Start Time
tSS_CHG
MIN
TYP
MAX
87
92
100
87
92
100
450
472
500
450
472
500
170
200
230
375
400
425
750
802
850
65
82
100
mA
20
30
40
mA
0
+5
1
+5
No DC or USB power
connected
UNITS
mA
µA
DC and/or USB power
connected, CEN = high
-5
Slew rate
450
Time from 0mA to 500mA
1.10
Time from 0mA to 100mA
0.22
Time from 100mA to 500mA
mA/ms
ms
0.88
Timer Accuracy
CCT = 0.15µF
-20
Timer Suspend Threshold
CISET voltage when the fast-charge timer
suspends; 300mV translates to 20% of the
maximum fast-charge current limit
250
Timer Extend Threshold
CISET voltage when the fast-charge timer
suspends; 750mV translates to 50% of the
maximum fast-charge current limit
700
+20
%
300
350
mV
750
800
mV
_______________________________________________________________________________________
7
MAX8671X
ELECTRICAL CHARACTERISTICS (continued)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
ELECTRICAL CHARACTERISTICS (continued)
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Prequalification Time
tPQ
CCT = 0.15µF
33
min
Fast-Charge Time
tFC
CCT = 0.15µF
660
min
Top-Off Time
tTO
15
s
THERMISTOR INPUT (THM) (VDC = 5.0V, EN = low)
THM Threshold, Cold
VTHMC
VTHM rising, 65mV hysteresis
73.0
74.0
75.5
% of
VVL
THM Threshold, Hot
VTHMH
VTHM falling, 65mV hysteresis
27.0
28.4
30.0
% of
VVL
-0.100
0.001
+0.200
THM Input Leakage Current
ITHM
THM = AGND or VL, TA = +25°C
THM = AGND or VL, TA = +85°C
0.01
µA
POWER SEQUENCING (Figures 11 and 12)
EN to REG3 Enable Delay
tD1
120
µs
REG1 Soft-Start Time
tSS1
2.6
ms
REG3 to REG1/2 Delay
tD2
0.4
ms
REG2 Soft-Start Time
tSS2
2.6
ms
REG3 Soft-Start Time
tSS3
2.6
ms
REG1/2 to REG4 Delay
tD3
0.3
ms
REG4 Soft-Start Time
tSS4
3.0
ms
REG5 Soft-Start Time
tSS5
3.0
ms
REGULATOR THERMAL SHUTDOWN
Thermal Shutdown Temperature
TJ rising
Thermal Shutdown Hysteresis
+165
°C
15
°C
REG1—SYNCHRONOUS STEP-DOWN CONVERTER
Input Voltage
PV1 supplied from SYS
Maximum Output Current
L = 4.7µH, RL = 0.13Ω (Note 7)
VSYS
FB1 Voltage
(Note 8)
0.997
Adjustable Output Voltage Range
mA
1.012
1
TA = +25°C
V
425
-50
-5
1.028
V
VSYS
V
+50
FB1 Leakage Current
VFB1 = 1.012V
Load Regulation
PWM mode
Line Regulation
PWM mode (Note 9)
p-Channel On-Resistance
VPV1 = 4V, ILX1 = 180mA
165
330
mΩ
n-Channel On-Resistance
VPV1 = 4V, ILX1 = 180mA
200
400
mΩ
0.615
0.675
A
p-Channel Current-Limit
Threshold
8
TA = +85°C
-5
0.555
nA
4.4
%/A
1
%/D
_______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
Skip Mode Transition Current
SYMBOL
CONDITIONS
MIN
(Note 10)
n-Channel Zero-Crossing
Threshold
Maximum Duty Cycle
Minimum Duty Cycle
PWM mode
Internal Oscillator Frequency
Internal Discharge Resistance in
Shutdown
EN = low, resistance from LX1 to PG1
TYP
MAX
UNITS
60
mA
10
mA
100
%
12.5
%
1.8
2.0
2.2
MHz
0.5
1.0
2.0
kΩ
REG2—SYNCHRONOUS STEP-DOWN CONVERTER
Input Voltage
PV2 supplied from SYS
VSYS
Maximum Output Current
L = 4.7µH, RL = 0.13Ω (Note 7)
FB2 Voltage
(Note 8)
425
0.997
Adjustable Output Voltage Range
mA
1.012
1
TA = +25°C
V
-50
-5
1.028
V
VSYS
V
+50
nA
FB2 Leakage Current
VFB2 = 1.012V
Load Regulation
PWM mode
Line Regulation
PWM mode (Note 9)
p-Channel On-Resistance
VPV2 = 4V, ILX2 = 180mA
200
400
mΩ
n-Channel On-Resistance
VPV2 = 4V, ILX2 = 180mA
150
265
mΩ
0.615
0.675
A
TA = +85°C
4.4
%/A
1
p-Channel Current-Limit
Threshold
Skip Mode Transition Current
-50
0.555
60
mA
n-Channel Zero-Crossing
Threshold
10
mA
Maximum Duty Cycle
100
%
Minimum Duty Cycle
(Note 10)
%/D
PWM mode
12.5
Internal Oscillator Frequency
Internal Discharge Resistance in
Shutdown
EN = low, resistance from LX2 to PG2
%
1.8
2.0
2.2
MHz
0.5
1.0
2.0
kΩ
REG3—SYNCHRONOUS STEP-DOWN CONVERTER
Input Voltage
PV3 supplied from SYS
VSYS
Maximum Output Current
L = 4.7µH, RL = 0.13Ω (Note 7)
FB3 Voltage
(Note 8)
425
0.997
Adjustable Output Voltage Range
mA
1.012
1
FB3 Leakage Current
VFB2 = 1.012V
Load Regulation
PWM mode
TA = +25°C
TA = +85°C
V
-50
-5
-50
4.4
1.028
V
VSYS
V
+50
nA
%/A
_______________________________________________________________________________________
9
MAX8671X
ELECTRICAL CHARACTERISTICS (continued)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
ELECTRICAL CHARACTERISTICS (continued)
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
Line Regulation
CONDITIONS
MIN
PWM mode (Note 9)
MAX
1
p-Channel Current-Limit
Threshold
0.555
Skip Mode Transition Current
TYP
(Note 10)
n-Channel Zero-Crossing
Threshold
0.615
UNITS
%/D
0.675
A
60
mA
10
mA
p-Channel On-Resistance
VPV3 = 4V, ILX3 = 180mA
230
460
mΩ
n-Channel On-Resistance
VPV3 = 4V, ILX3 = 180mA
120
210
mΩ
100
%
PWM mode
12.5
%
Maximum Duty Cycle
Minimum Duty Cycle
Internal Oscillator Frequency
Internal Discharge Resistance in
Shutdown
EN = low, resistance from LX3 to PG3
1.8
2.0
2.2
MHz
0.5
1.0
2.0
kΩ
VSYS
V
REG4—LINEAR REGULATOR
PV4 Operating Range
VPV4
1.7
PV4 Undervoltage Lockout
Threshold
VPV4 rising, 100mV hysteresis
1.55
1.60
1.65
V
FB4 Voltage
No load
0.582
0.600
0.618
V
-50
-5
+50
FB4 Leakage Current
Drop-Out Resistance
Current Limit
Output Noise
PSRR
Internal Discharge Resistance in
Shutdown
10
VFB4 = 0.6V
TA = +25°C
TA = +85°C
-5
PV4 to OUT4, VPV4 = 3.3V
0.45
PV4 to OUT4, VPV4 = 2.0V
0.75
1.8
230
265
VFB4 = 0.54V
200
VFB4 = 0V
235
10Hz to 100kHz;
COUT4 = 3.3µF, IOUT4 = 10mA, VPV4 = 2V,
VOUT4 set for 1.8V
120
f = 1kHz, IOUT4 = 10mA, VPV4 = 2V,
VOUT4 set for 1.8V
67
f = 10kHz, IOUT4 = 10mA, VPV4 = 2V,
VOUT4 set for 1.8V
50
EN = low, resistance from OUT4 to AGND
nA
Ω
mA
µVRMS
dB
0.5
1.0
______________________________________________________________________________________
2.0
kΩ
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
VSYS
V
REG5—LINEAR REGULATOR
PV5 Operating Range
VPV5
1.7
PV5 Undervoltage Lockout
Threshold
VPV5 rising, 100mV hysteresis
1.55
1.60
1.65
V
FB5 Voltage
No load
0.582
0.600
0.618
V
FB5 Leakage Current
VFB5 = 0.6V
-50
-5
+50
Drop-Out Resistance
TA = +25°C
TA = +85°C
VPV5 to OUT5, VPV5 = 3.3V
0.45
VPV5 to OUT5, VPV5 = 2.0V
0.75
1.8
230
265
VFB5 = 0.54V
Current Limit
Output Noise
PSRR
Internal Discharge Resistance in
Shutdown
-5
200
VFB5 = 0V
235
10Hz to 100kHz,
COUT5 = 2.2µF, IOUT5 = 10mA, VPV5 = 3.5V,
VOUT5 set for 3.3V
180
f = 1kHz, IOUT5 = 10mA, VPV5 = 3.5V,
VOUT5 set for 3.3V
62
f = 10kHz, IOUT5 = 10mA, VPV5 = 3.5V,
VOUT5 set for 3.3V
44
nA
Ω
mA
µVRMS
dB
EN = low, resistance from OUT5 to AGND
0.5
1.0
2.0
kΩ
IVL = 0mA to 3mA
3.0
3.3
3.6
V
0.6
V
VL—LINEAR REGULATOR
VL Voltage
VVL
LOGIC (UOK, DOK, PEN1, PEN2, USUS, CEN, CST1, CST2, EN, PWM)
Logic Input-Voltage Low
VUSB or VDC = 4.1V to 6.6V, VSYS = 2.6V to
5.5V
Logic Input-Voltage High
VUSB or VDC = 4.1V to 6.6V, VSYS = 2.6V to
5.5V
Logic Input Leakage Current
VLOGIC = 0V to 5.5V
Logic Output-Voltage Low
ISINK = 1mA
Logic Output-High Leakage
Current
VLOGIC = 5.5V
1.3
V
TA = +25°C
0.001
TA = +85°C
0.01
1
10
30
TA = +25°C
0.001
1
TA = +85°C
0.01
µA
mV
µA
TRI-STATE INPUT (BVSET)
BVSET Input-Voltage Low
BVSET Input-Voltage Mid
VUSB or VDC = 4.1V to 6.6V
0.3
V
VUSB or VDC = 4.1V to 6.6V
VVL 1.2
V
1.2
______________________________________________________________________________________
11
MAX8671X
ELECTRICAL CHARACTERISTICS (continued)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
ELECTRICAL CHARACTERISTICS (continued)
(DC, USB, BVSET, UOK, DOK, LX_ unconnected; VTHM = VL/2, VPG_ = VAGND = 0V, VBAT = 4V, CEN = low, USUS = low, EN = high,
VPEN1 = VPEN2 = 3.3V, VPWM = 0V, COUT4 = 1µF, COUT5 = 1µF, CSYS = 10µF, PV1 = PV2 = PV3 = PV4 = PV5 = SYS, RDISET = 3kΩ,
RCISET = 3kΩ, CVL = 0.1µF, CCT = 0.15µF, CBP = 0.01µF, VFB1 = 1.1V, VFB2 = 1.1V, VFB3 = 1.1V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
BVSET Input-Voltage High
CONDITIONS
VUSB or VDC = 4.1V to 6.6V
MIN
VVL 0.3
Internal BVSET Pullup Resistance
External BVSET Pulldown
Resistance for Midrange Voltage
TYP
MAX
UNITS
VVL +
0.3
V
52.5
RBVSET
45
50
kΩ
55
kΩ
Note 2: Limits are 100% production tested at TA = +25°C. Limits over the operating temperature range are guaranteed through correlation using statistical quality control (SQC) methods.
Note 3: The USB/DC current limit does not include the VL output current. See the VL Linear Regulator section for more information.
Note 4: Quiescent current excludes the energy needed for the REG1–REG5 external resistor-dividers. All typical operating characteristics include the energy for the REG1–REG5 external resistor-dividers. For the circuit of Figure 1, the typical quiescent
current with DC and USB unconnected, EN = high, VBAT = 4V, and PWM = low is 175µA.
Note 5: The charger transitions from done to fast-charge mode at this BAT recharge threshold (Figure 7).
Note 6: The charger transitions from fast-charge to top-off mode at this top-off threshold (Figure 7).
Note 7: The maximum output current is guaranteed by correlation to the p-channel current-limit threshold, p-channel on-resistance,
n-channel on-resistance, oscillator frequency, input voltage range, and output voltage range. The parameter is stated for a
4.7µH inductor with 0.13Ω series resistance. See the Step-Down Converter Output Current section for more information.
Note 8: The step-down output voltages are 1% high with no load due to the load-line architecture. When calculating the external
resistor-dividers, use an FB_ voltage of 1.000V.
Note 9: Line regulation for the step-down converters is measured as ΔVOUT/ΔD, where D is the duty cycle (approximately
VOUT/VIN).
Note 10: The skip mode current threshold is the transition point between fixed-frequency PWM operation and skip mode operation.
The specification is given in terms of output load current for inductor values shown in the typical application circuits.
12
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
FALLING
0.6
RISING
0.4
1.0
0.8
0.6
FALLING
0.4
RISING
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.2
0.2
0.05
0
0
0
4
6
8
10
12
14
16
0
2
4
INPUT VOLTAGE (V)
6
8
10
12
14
1.4
1.2
1.0
0.8
0.6
VUSB = 5V
VDC = 0V
PEN1 = PEN2 = 1
EN = 1
0.2
0
0
0
2
4
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
BATTERY VOLTAGE (V)
6
8
10
12
14
16
USB VOLTAGE (V)
BATTERY LEAKAGE CURRENT
vs. BATTERY VOLTAGE WHEN
REGULATORS ARE POWERED FROM USB
0.4
16
USB VOLTAGE RISING
INPUT VOLTAGE (V)
BATTERY LEAKAGE CURRENT
vs. BATTERY VOLTAGE
0.8
BATTERY LEAKAGE CURRENT (μA)
2
MAX8671X toc04
0
MAX8671X toc03
1.2
0.50
NO EXTERNAL POWER
EN = LOW
CEN = HIGH
0.7
MAX8671X toc05
0.8
CHARGER ENABLED
NO BATTERY INPUT
VOLTAGE AT DC OR
USB WITH THE
OTHER INPUT LEFT
UNCONNECTED
1.4
USB CURRENT (mA)
1.0
BATTERY LEAKAGE CURRENT (μA)
INPUT CURRENT (mA)
1.2
1.6
INPUT CURRENT (mA)
CHARGER ENABLED
NO BATTERY INPUT
VOLTAGE AT DC OR
USB WITH THE
OTHER INPUT LEFT
UNCONNECTED
1.4
MAX8671X toc01
1.6
USB QUIESCENT CURRENT
vs. USB SUPPLY VOLTAGE, USB SUSPEND
QUIESCENT CURRENT
vs. DC OR USB SUPPLY VOLTAGE
MAX8671X toc02
QUIESCENT CURRENT
vs. DC OR USB SUPPLY VOLTAGE
0.6
0.5
0.4
0.3
0.2
0.1
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
BATTERY VOLTAGE (V)
______________________________________________________________________________________
13
MAX8671X
Typical Operating Characteristics
(Circuit of Figure 1, IVL = 0mA, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(Circuit of Figure 1, IVL = 0mA, TA = +25°C, unless otherwise noted.)
CHARGE CURRENT vs. BATTERY
VOLTAGE WITH USB INPUT
PEN2 = 1
VUSB = 5.0V
VDC = 0V
PEN1 = 1, PEN2 = 1
450
400
CHARGE CURRENT (mA)
350
300
250
200
150
350
RCISET = 10kΩ
300
250
RCISET = 6.04kΩ
200
150
100
100
PEN2 = 0
50
50
0
0
2.5
3.0
3.5
4.0
2.0
4.5
2.5
BATTERY VOLTAGE (V)
CHARGE CURRENT vs. AMBIENT
TEMPERATURE, LOW POWER DISSIPATION
500
350
300
250
VUSB = 5.0V
VDC = 0V
VBAT = 4.0V
PEN1 = 1
200
150
450
PEN2 = 1
400
100
350
300
VUSB = 6.5V
VDC = 0V
VBAT = 3.1V
PEN1 = 1
250
200
150
PEN2 = 0
4.40
-15
10
35
60
85
4.20
4.15
-15
10
35
60
-40
85
VSYS vs. SYS CURRENT
5.00
10
35
60
85
VSYS vs. SYS CURRENT
5.50
MAX8671X toc12
MAX8671X toc11
5.50
-15
AMBIENT TEMPERATURE (°C)
AMBIENT TEMPERATURE (°C)
VSYS vs. SYS CURRENT
4.05
4.25
4.00
-40
AMBIENT TEMPERATURE (°C)
4.10
4.30
4.05
0
-40
4.35
4.10
PEN2 = 0
50
0
VUSB = 5V
VDC = 0V
PEN1 = 1
PEN2 = 0
BVSET = VL
NO LOAD
4.45
100
50
4.5
4.50
BATTERY VOLTAGE (V)
CHARGE CURRENT (mA)
400
4.0
BATTERY REGULATION VOLTAGE
vs. TEMPERATURE
MAX8671X toc09
PEN2 = 1
CHARGE CURRENT (mA)
450
3.5
CHARGE CURRENT vs. AMBIENT
TEMPERATURE, HIGH IC POWER DISSIPATION
MAX8671X toc08
500
3.0
BATTERY VOLTAGE (V)
MAX8671X toc10
2.0
MAX8671X toc13
CHARGE CURRENT (mA)
400
500
MAX8671X toc07
VUSB = 5.0V
VDC = 0V
PEN1 = 1
450
CHARGE CURRENT
vs. BATTERY VOLTAGE
MAX8671X toc06
500
5.00
3.95
4.50
VSYS (V)
VSYS (V)
4.00
VSYS (V)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
4.00
4.50
4.00
3.90
DC OPEN, USB OPEN, VBAT = 4.0V
THE SLOPE SHOWS THE SYSTEM LOAD
SWITCH HAS AN ON-RESISTANCE OF 81mΩ.
3.85
3.50
3.80
0
200
400
600
SYS CURRENT (mA)
14
800
3.50
DC OPEN, VUSB = 5.1V, VBAT = 4.0V
PEN1 = 1, PEN2 = 0, CHARGER DISABLED
DC OPEN, VUSB = 5.1V, VBAT = 4.0V
PEN1 = 1, PEN2 = 0, CHARGER DISABLED
1000
3.00
3.00
0
200
400
600
SYS CURRENT (mA)
800
1000
0
200
400
600
SYS CURRENT (mA)
______________________________________________________________________________________
800
1000
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
USB CONNECT (50mA SYS LOAD)
USB CONNECT (NO SYS LOAD)
IUSB
VSYS
4.0V
4.14V
2V/div
VUOK
IBAT
5V/div
VSYS
4.14V
4.0V
2V/div
VUOK
IBAT
0mA
MAX8671X toc16
5V/div
VUSB
500mA/div
IUSB
VUSB
5V/div
500mA/div
IUSB
VUSB
USB DISCONNECT (50mA SYS LOAD)
MAX8671X toc15
MAX8671X toc14
5V/div
500mA/div
4.14V
4.0V
VSYS
2V/div
5V/div
5V/div
VUOK
+50mA
-425mA CHARGING
-475mA CHARGING
500mA/div
IBAT
500mA/div
+50mA
500mA/div
-425mA CHARGING
2ms/div
0mA LOAD ON SYS, 4.0V BATTERY, 5.0V USB INPUT
2ms/div
50mA LOAD ON SYS, 4.0V BATTERY, 5.0V USB INPUT
2ms/div
50mA LOAD ON SYS, 4.0V BATTERY, 5.0V USB INPUT
USB RESUME
USB SUSPEND
MAX8671X toc18
MAX8671X toc17
VUSB
5V/div
IUSB
500mA/div
VSYS
4.14V
4.0V
VSYS
5V/div
VCST2
+50mA
IBAT -425mA
500mA/div
400μs/div
50mA LOAD ON SYS, 4.0V BATTERY, 5.0V USB INPUT
5V/div
500mA/div
IUSB
2V/div
5V/div
VCST1
VUSUS
4.0V
4.14V
2V/div
VCST1
VCST2
IBAT
5V/div
5V/div
+50mA
-425mA
500mA/div
400μs/div
50mA LOAD ON SYS, 4.0V BATTERY, 5.0V USB INPUT
______________________________________________________________________________________
15
MAX8671X
Typical Operating Characteristics (continued)
(Circuit of Figure 1, IVL = 0mA, TA = +25°C, unless otherwise noted.)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Typical Operating Characteristics (continued)
(Circuit of Figure 1, IVL = 0mA, TA = +25°C, unless otherwise noted.)
4.0V
4.14V
1A
5V/div
VSYS
4.14V
4V
1A
500mA/div
2V/div
4V
VSYS
500mA/div
IBAT
2V/div
500mA/div
IDC
IUSB
IUSB
+160mA
-840mA
-330mA
500mA/div
500mA/div IBAT
500mA/div
+160mA
-330mA
500mA/div
-840mA
-840mA
20ms/div
25Ω LOAD ON SYS, PEN1 = PEN2 = HIGH 1A DC LIMIT
400μs/div
25Ω LOAD ON SYS, PEN1 = PEN2 = HIGH 1A DC
LIMIT
400μs/div
25Ω LOAD ON SYS, PEN1 = PEN2 = HIGH 1A DC
LIMIT, RDISET = 3.01kΩ
POWER-UP SEQUENCING
MAX8671X toc22
5V/div
VEN
5V/div
VOUT1
5V/div
VOUT2
2V/div
VOUT3
5V/div
VOUT4
5V/div
VOUT5
5V/div
VVL
IUSB
50mA/div
4ms/div
16
4.14V
1A
500mA/div
IDC
IDC
IBAT
MAX8671X toc21
MAX8671X toc20
MAX8671X toc19
VSYS
AC-TO-DC ADAPTER DISCONNECT
WITH USB
AC-TO-DC ADAPTER CONNECT
WITH NO USB
AC-TO-DC ADAPTER CONNECT WITH USB
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
2.860
70
OUTPUT VOLTAGE (V)
PWM = 0
VOUT1 = 2.8V
60
50
40
30
PWM = 1
VOUT1 = 2.8V
20
10
VBATT = 4V
0
160
2.840
2.820
2.800
2.780
2.760
140
120
100
80
60
2.740
40
2.720
20
0
2.700
1
10
1000
100
0
50
100
150
200
OUTPUT CURRENT (mA)
REG1 LIGHT-LOAD SWITCHING
WAVEFORMS (PWM = 0)
REG1 LIGHT-LOAD SWITCHING
WAVEFORMS (PWM = 1)
20mV/div
VOUT1
(AC-COUPLED)
200
300
400
500
REG1 HEAVY-LOAD SWITCHING
WAVEFORMS
MAX8671X toc28
VOUT1
10mV/div
VLX1
2V/div
ILI
100
MAX8671X toc27
MAX8671X toc26
VLX1
0
250
OUTPUT CURRENT (mA)
LOAD CURRENT (mA)
VOUT1
THE NOMINAL INDUCTOR DC RESISTANCE
IS 140mΩ. THE NOMINAL p-CHANNEL
RESISTANCE OF THE REGULATOR IS
200mΩ AT 2.8V AND 185mΩ AT 3.3V.
THE SLOPE OF THE LINE SHOWS
THAT THE TOTAL DROPOUT
RESISTANCE OF AN AVERAGE
PART, BOARD, INDUCTOR
COMBINATION IS
VOUT1 = 3.3V
330mΩ AT 3.3V
AND 354mΩ
VOUT1 = 2.8V
AT 2.8V.
SYS IS 100mV BELOW THE
REG1 NOMINAL REGULATION
VOLTAGE.
180
DROPOUT VOLTAGE (mV)
80
RFBH = 182kΩ
RFBL = 100kΩ
2.880
200
MAX8671X toc24
90
EFFICIENCY (%)
2.900
MAX8671X toc23
100
REG1 DROPOUT VOLTAGE
vs. LOAD CURRENT
REG1 LOAD REGULATION
MAX8671X toc25
REG1 EFFICIENCY vs. LOAD CURRENT
2V/div
10mV/div
(AC-COUPLED)
VLX1
2V/div
0
0
0
200mA/div
100mA/div
100mA/div
ILI
ILI
0
0
20mA LOAD
0
20mA LOAD
20mA LOAD
200ns/div
4μs/div
400ns/div
REG1 LINE TRANSIENT
REG1 LOAD TRANSIENT
MAX8671X toc29
MAX8671X toc30
5.3V
VSYS
3.3V
3.3V
2V/div
50mV/div
(AC-COUPLED)
VOUT1
250mA
VOUT1
20mV/div
IOUT1
25mA
25mA
100mA/div
25mA LOAD
100μs/div
20μs/div
______________________________________________________________________________________
17
MAX8671X
Typical Operating Characteristics (continued)
(Circuit of Figure 1, IVL = 0mA, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(Circuit of Figure 1, IVL = 0mA, TA = +25°C, unless otherwise noted.)
REG2 LOAD REGULATION
REG2 EFFICIENCY vs. LOAD CURRENT
90
OUTPUT VOLTAGE (V)
80
70
PWM = 0
VOUT2 = 1.5V
60
PWM = 1
VOUT2 = 1.5V
50
40
30
MAX8671X toc32
1.60
MAX8671X toc31
100
EFFICIENCY (%)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
1.55
1.50
1.45
20
10
VBATT = 4.0V
1.40
0
10
100
0
1000
50
REG3 EFFICIENCY vs. LOAD CURRENT
90
1.26
PWM = 1
VOUT2 = 1.2V
40
RFBH = 20kΩ
RFBL = 100kΩ
1.28
70
50
250
200
REG3 LOAD REGULATION
OUTPUT VOLTAGE (V)
EFFICIENCY (%)
80
PWM = 0
VOUT2 = 1.2V
150
1.30
MAX8671X toc33
100
60
100
OUTPUT CURRENT (mA)
LOAD CURRENT (mA)
30
20
MAX8671X toc34
1
1.24
1.22
1.20
1.18
1.16
1.14
10
1.12
VBATT = 4.0V
0
1.10
1
10
100
1000
0
50
LOAD CURRENT (mA)
OUT3 LIGHT-LOAD SWITCHING
WAVEFORMS (PWM = 0)
100
150
200
250
OUTPUT CURRENT (mA)
OUT3 HEAVY-LOAD SWITCHING
WAVEFORMS
MAX8671X toc35
OUT3 LOAD TRANSIENT
MAX8671X toc37
MAX8671X toc36
PWM = 0
20mV/div VOUT1
VOUT1
10mV/div
VOUT1
2V/div
VLX1
100mV/div
2V/div
VLX1
0
250mA
0
10mA LOAD
IL1
200mA/div
IL1
200mA/div
IOUT1
25mA
25mA
100mA/div
250mA LOAD
10μs/div
18
400ns/div
40μs/div
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
REG4 LOAD REGULATION
MAX8671X toc40
MAX8671X toc39
MAX8671X toc38
RFBH = 316kΩ
RFBL = 100kΩ
2.552
2.550
5.3V
VPV4
2V/div
3.3V
3.3V
50mV/div
VOUT4
2.548
2.546
2.544
2.542
150mA
2.540
10mV/div
VOUT4
2.538
2.536
2.534
100
50
150
50mA
50mA
100mV/div
VPV4 = VSYS = 4V
VOUT4 = 2.5V
40μs/div
100μs/div
OUTPUT CURRENT (mA)
REG5 LOAD TRANSIENT
REG5 LOAD REGULATION
MAX8671X toc42
3.260
MAX8671X toc41
0
IOUT4
PV = SYS
13.4Ω LOAD
VSYS = 4V
3.258
3.256
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
REG4 LOAD TRANSIENT
REG4 LINE TRANSIENT
2.554
50mV/div
VOUT5
3.254
3.252
3.250
3.248
150mA
3.246
3.244
IOUT5
3.242
0
50
100
OUTPUT CURRENT (mA)
100mV/div
VUSB = 5V,
VOUT5 = 3.3V
VUSB = 5V
3.240
50mA
50mA
150
40μs/div
______________________________________________________________________________________
19
MAX8671X
Typical Operating Characteristics (continued)
(Circuit of Figure 1, IVL = 0mA, TA = +25°C, unless otherwise noted.)
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
MAX8671X
Pin Description
PIN
20
NAME
FUNCTION
USB Suspend Digital Input. As shown in Table 1, driving USUS high suspends the DC or USB inputs
if they are configured as a USB power input.
1
USUS
2
DC
DC Power Input. DC is capable of delivering 1A to SYS. DC supports both AC adaptors and USB
inputs. As shown in Table 1, the DC current limit is controlled by PEN1, PEN2, USUS, and RDISET.
3
USB
USB Power Input. USB is capable of delivering 0.5A to SYS. As shown in Table 1, the USB current
limit is controlled by PEN1, PEN2, and USUS.
4
FB5
Feedback Input for REG5. Connect FB5 to the center of a resistor voltage-divider from OUT5 to
AGND to set the REG5 output voltage from 0.6V to VPV5.
5
PV5
Power Input for REG5. Connect PV5 to SYS, or a supply between 1.7V and VSYS. Bypass PV5 to
power ground with a 1µF ceramic capacitor.
6
OUT5
7
PG2
Power Ground for the REG2 Step-Down Regulator
8
LX2
Inductor Switching Node for REG2. LX2 is internally pulled to PG2 by 1kΩ in shutdown.
9
PV2
Power Input for the REG2 Step-Down Regulator. Connect PV2 to SYS. Bypass PV2 to PG2 with a
4.7µF ceramic capacitor.
10
CEN
Active-Low Charger Enable Input. Pull CEN low to enable the charger, or drive CEN high to disable
charging. The battery charger is also disabled when USUS is high.
11
FB2
Feedback Input for REG2. Connect FB2 to the center of a resistor voltage-divider from the REG2
output capacitors to AGND to set the output voltage from 1V to VSYS.
12
DOK
Active-Low, Open-Drain DC Power-OK Output. DOK is low when VDC is within its valid operating
range.
13
FB4
Feedback Input for REG4. Connect FB4 to the center of a resistor voltage-divider from the REG4
output capacitors to AGND to set the output voltage from 0.6V to VPV4.
14
BP
Reference Noise Bypass. Bypass BP with a low-leakage 0.01µF ceramic capacitor for reduced noise
on the LDO outputs.
15
OUT4
16
PV4
17
BVSET
18
AGND
Linear Regulator Power Output. OUT5 is internally pulled to AGND by 1kΩ in shutdown.
Linear Regulator Power Output. OUT4 is internally pulled to AGND in shutdown.
Power Input for REG4. Connect PV4 to SYS, or a supply between 1.7V and VSYS. Bypass PV4 to
power ground with a 1µF ceramic capacitor.
Battery Regulation Voltage Set Node. Drive BVSET low to set the regulation voltage to 4.1V. Connect
BVSET to VL or leave unconnected to set the regulation voltage to 4.2V. Connect BVSET to AGND
through a 50kΩ resistor to set the regulation voltage to 4.350V.
Ground. AGND is the low-noise ground connection for the internal circuitry.
19
FB1
Feedback Input for REG1. Connect FB1 to the center of a resistor voltage-divider from the REG1
output capacitors to AGND to set the output voltage from 1V to VSYS.
20
EN
Regulator Enable Input. Drive EN high to enable all regulator outputs. The sequencing is shown in
Figure 11. Drive EN low to disable the regulators.
21
PWM
Forced-PWM Input. Connect PWM high for forced-PWM operation on REG1, REG2, and REG3.
Connect PWM low for auto PWM operation. Do not change PWM on-the-fly. See the PWM section
for more information.
22
PV1
Power Input for the REG1 Step-Down Regulator. Connect PV1 to SYS. Bypass PV1 to PG1 with a
4.7µF ceramic capacitor.
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
PIN
NAME
FUNCTION
23
LX1
Inductor Switching Node for REG1. LX1 is internally pulled to PG1 by 1kΩ in shutdown.
24
PG1
Power Ground for the REG1 Step-Down Regulator
25
PG3
Power Ground for the REG3 Step-Down Regulator
26
LX3
Inductor Switching Node for REG3. LX3 is internally pulled to PG3 by 1kΩ in shutdown.
27
PV3
Power Input for the REG3 Step-Down Regulator. Connect PV3 to SYS. Bypass PV3 to PG3 with a
4.7µF ceramic capacitor.
28
VL
IC Supply Output. VL is an LDO output that powers the MAX8671X internal battery-charger circuitry.
VL provides 3.3V at 3mA to power external circuitry when DC or USB is present. Connect a 0.1µF
capacitor from VL to AGND.
29
FB3
30
DISET
DC Input Current-Limit Select Input. Connect a resistor from DISET to AGND (RDISET) to set the DC
current limit. See Table 2 for more information.
31
CISET
Charge Rate Select Input. Connect a resistor from CISET to AGND (RCISET) to set the fast-charge
current limit, prequalification-charge current limit, and top-off threshold.
32
CT
Feedback Input for REG3. Connect FB3 to the center of a resistor voltage-divider from the REG3
output capacitors to AGND to set the output voltage from 1V to VSYS.
Charge Timer Programming Node. Connect a capacitor from CT to AGND (CCT) to set the time
required for a fault to occur in fast-charge or prequalification modes. Connect CT to AGND to disable
the fast-charge and prequalification timers.
33
THM
Thermistor Input. Connect a negative temperature coefficient (NTC) thermistor that has a good
thermal contact with the battery from THM to AGND. Connect a resistor equal to the thermistor
resistance at +25°C from THM to VL. Charging is suspended when the battery is outside the hot or
cold limits.
34
BAT
Positive Battery Terminal Connection. Connect BAT to the positive terminal of a single-cell Li+/Li-Poly
battery.
System Supply Output. Bypass SYS to power ground with a 10µF ceramic capacitor.
35
SYS
When a valid voltage is present at USB or DC and not suspended (USUS = low), SYS is limited to
5.3V (VSYS-REG). When the system load (ISYS) exceeds the input current limit, SYS drops below VBAT
by VBSREG allowing both the external power source and the battery service SYS.
SYS is connected to BAT through an internal system load switch (RBS) when a valid source is not
present at USB or DC.
36
PEN1
Input Current-Limit Control 1. See Table 1 for more information.
37
CST2
Open-Drain Charger Status Output 2. CST1 and CST2 indicate four different charger states. See
Table 3 for more information.
38
UOK
Active-Low, Open-Drain USB Power-OK Output. UOK is low when VUSB is within its valid operating
range.
39
CST1
Open-Drain Charger Status Output 1. CST1 and CST2 indicate four different charger states. See
Table 3 for more information.
40
PEN2
Input Current-Limit Control 2. See Table 1 for more information.
—
EP
Exposed Paddle. Connect the exposed paddle to AGND. Connecting the exposed paddle does not
remove the requirement for proper ground connections to AGND, PG1, PG2, and PG3.
______________________________________________________________________________________
21
MAX8671X
Pin Description (continued)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
2
AC-TO-DC ADAPTER
SYS
DC
35
3
VBUS
USB
BAT
34
4.7μF
3.3V
3mA
VL
18
15
2.2μF
OUT2
1.0μF
16
VL
10kΩ
VL
THM
0.1μF
121kΩ
BAT
4.7μF
28
1.8V
180mA
OUT4
SYS
10μF
4.7μF
33
10kΩ
β = 3380K
AGND
MAX8671X
OUT4
PV4
LX1
23
T
+
4.7μH
0.6A
Li+/Li-Poly
2.8V
425mA
OUT1
182kΩ
13
60.4kΩ
3.3V
180mA
OUT5
6
FB4
FB1
PV1
2.2μF
100kΩ
PV5
SYS
1.0μF
PG1
LX2
60.4kΩ
ON
4
FB5
FB2
PV2
24
4.7μH
0.6A
11
9
40
1
10
PG2
PWM
7
4.7μH
0.6A
PEN1
PEN2
USUS
CEN
FB3
PV3
1.2V
425mA
OUT3
26
29
27
20kΩ
2x
10μF
SYS
100kΩ
4.7μF
IO
μP
4x
560kΩ
5%
2x
10μF
SYS
4.7μF
LX3
36
100kΩ
100kΩ
EN
21
2.0V
425mA
OUT2
8
20
OFF
2x
10μF
SYS
4.7μF
OUT5
5
274kΩ
19
22
PG3
39
37
12
38
BVSET
CST1
BP
CST2
DISET
DOK
25
17
14
30
31
UOK
0.01μF
3kΩ
CISET
CT
EP
32
3kΩ
0.15μF
Figure 1. MAX8671X Typical Application Circuit
22
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
MAX8671X
SYS
DC
DOK
DISET
PEN1
SMART
POWER
SELECTOR
PEN2
USUS
Li+/Li-Poly BATTERY
CHARGER AND
SYSTEM LOAD
SWITCH
BAT
BVSET
UOK
CST2
CST1
USB
THM
CEN
HIGHEST
VOLTAGE
SELECTOR
CT
CISET
VL
IN
OUT
SMART POWER
SELECTOR AND
CHARGER BIAS
3.3V
LDO
MAX8671X
AGND
PV4
OUT4
PV1
REG4
LDO
FB4
REG1
DC-DC
LX1
PG1
FB1
BP
PV2
REF
REG2
DC-DC
PV5
LX2
PG2
FB2
OUT5
REG5
LDO
FB5
EN
PWM
PV3
REG3
DC-DC
LX3
PG3
FB3
Figure 2. Functional Diagram
______________________________________________________________________________________
23
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Detailed Description
The MAX8671X highly integrated PMIC is ideally suited
for use in portable audio player and handheld applications. As shown in Figure 2, the MAX8671X integrates
USB power input, AC-to-DC adapter power input (DC),
Li+/Li-Poly battery charger, three step-down regulators,
two linear regulators, and various monitoring and status
outputs. The MAX8671X offers adjustable output voltages for all outputs.
Smart Power Selector
The MAX8671X Smart Power Selector seamlessly distributes power between the two current-limited external
inputs (USB and DC), the battery (BAT), and the system load (SYS). The basic functions performed are:
• With both an external power supply (USB or DC)
and battery (BAT) connected:
When the system load requirements are less than
the input current limit, the battery is charged with
residual power from the input.
When the system load requirements exceed the
input current limit, the battery supplies supplemental current to the load through the internal system load switch.
• When the battery is connected and there is no external power input, the system (SYS) is powered from
the battery.
• When an external power input is connected and
there is no battery, the system (SYS) is powered
from the external power input.
The dual-input Smart Power Selector supports end
products with dual and single external power inputs.
For end products with dual external power inputs, connect these inputs directly to the DC and USB nodes of
the MAX8671X. For end products with a single input,
connect the single input to the DC node and connect
USB to ground or leave it unconnected. In addition to
AC-to-DC adapters current limits, the DC input also
supports USB current limit to allow for end products
Table 1. Input Limiter Control Logic
POWER SOURCE
AC-to-DC Adapter at
DC Input
DOK
UOK
PEN1
PEN2
USUS
DC INPUT
CURRENT
LIMIT
USB INPUT
CURRENT
LIMIT
L
X
H
X
X
IDCLIM
L
X
L
L
L
100mA
L
X
L
H
L
500mA
Lower of ICHGMAX
and
500mA
L
X
L
X
H
Suspend
0
H
L
X
L
L
H
L
X
H
L
H
L
X
X
H
H
X
X
Lower of ICHGMAX
and
IDCLIM
USB input off,
DC input has
priority
USB Power at DC Input
Lower of ICHGMAX
and
100mA
100mA
Lower of ICHGMAX
and
100mA
500mA
Lower of ICHGMAX
and
500mA
H
Suspend
0
X
No USB input
0
USB Power at USB
Input, DC Unconnected
DC and USB
Unconnected
MAXIMUM
CHARGE
CURRENT*
No DC input
*Charge current cannot exceed the input current limit. Charge can be less than the maximum charge current if the total SYS load
exceeds the input current limit.
X = Don’t care.
24
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
A thermal-limiting circuit reduces the battery charger
rate and external power-source current to prevent the
MAX8671X from overheating.
System Load Switch
An internal 80mΩ (RBS) MOSFET connects SYS to BAT
when no voltage source is available at DC or USB.
When an external source is detected at DC or USB, this
switch is opened and SYS is powered from the valid
input source through the Smart Power Selector.
When the system load requirements exceed the input
current limit, the battery supplies supplemental current
to the load through the internal system load switch. If
the system load continuously exceeds the input current
limit, the battery does not charge, even though external
power is connected. This is not expected to occur in
most cases because high loads usually occur only in
short peaks. During these peaks, battery energy is
used, but at all other times the battery charges.
USB Power Input (USB)
USB is a current-limited power input that supplies the
system (SYS) up to 500mA. The USB to SYS switch is a
linear regulator designed to operate in dropout. This linear regulator prevents the SYS voltage from exceeding
5.3V. USB is typically connected to the VBUS line of the
universal serial bus (USB) interface. As shown in Table
1, USB supports three different current limits that are
set with the PEN2 and USUS digital inputs. These current limits are ideally suited for use with USB power.
The operating voltage range for USB is 4.1V to 6.6V,
but it can tolerate up to 14V without damage. When the
USB input voltage is below the undervoltage threshold
(VUSBL, 4V typ) it is considered invalid. Similarly, if the
USB voltage is above the overvoltage threshold
(VUSBH, 6.9V typ) it is considered invalid. When the
USB voltage is below the battery voltage, it is considered invalid. The USB power input is disconnected
when the USB voltage is invalid. As shown in Table 1,
when power is available at the DC input, it has priority
over the USB input. Bypass USB to ground with at least
a 4.7µF capacitor.
To support USB power sources at the USB input drive
PEN2 and USUS to select between three internally set
USB-related current limits as shown in Table 1. Choose
100mA for low-power USB mode. Choose 500mA for
high-power USB mode. Choose suspend to reduce the
USB current to 0.11mA (typ) for both USB suspend
mode and unconfigured OTG mode. To comply with
the USB 2.0 specification, each device must be initially
configured for low power. After USB enumeration, the
device can switch from low power to high power if
given permission from the USB host. The MAX8671X
does not perform enumeration. It is expected that the
system communicates with the USB host and commands the MAX8671X through its PEN1, PEN2, and
USUS inputs. When the load exceeds the input current
limit, SYS drops to 82mV below BAT and the battery
supplies supplemental load current.
The MAX8671X reduces the USB current limit by 5%/°C
when the die temperature exceeds +100°C. The system load (ISYS) has priority over the charger current, so
input current is first reduced by lowering charge current. If the junction temperature still reaches +120°C in
spite of charge current reduction, no input current is
drawn from USB; the battery supplies the entire load
and SYS is regulated below BAT by VBSREG. Note that
this on-chip thermal-limiting circuit is not related to and
operates independently from the thermistor input.
If the USB power input is not required, connect USB to
ground or leave it unconnected. When both DC and
USB inputs are powered, the DC input has priority.
______________________________________________________________________________________
25
MAX8671X
with a single power input to operate from either an ACto-DC adapter or USB host (see Table 1).
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
USB Power-OK Output (UOK)
As shown Figure 3, the USB power-OK output (UOK) is
an active-low open-drain output. The UOK output pulls
low when the voltage from USB to AGND (V USB) is
between VUSBH (typically 6.9V) and VUSBL (typically
4.0V).
The USB power-OK circuitry remains active in thermal
overload and USB suspend. If the USB power-OK output feature is not required, connect UOK to ground or
leave unconnected.
USB Suspend (USUS)
As shown in Table 1, driving USUS high suspends the
DC or USB inputs if they are configured as a USB
power input. The suspend current is 110µA when USUS
is driven high allowing the MAX8671X to comply with
the USB 1.1/2.0 specification for USB suspend as well
as the USB OTG specification for an unconfigured
device. If an external input (USB or DC) is connected to
the MAX8671X and suspended, the SYS node is supported by the battery. The DOK, UOK, and VL circuits
remain active in USB suspend mode.
A common assumption is that REG5 is disabled in USB
suspend. This is not true. REG5 is not affected by the
USB suspend mode. While in suspend, a USB device
must provide the 3.3V termination to the USB transceivers’ pullup resistors. This 3.3V termination can
come from the MAX8671X’s VL output or REG5. Both
remain enabled in USB suspend.
DC Power Input (DC)
DC is a current-limited power input that supplies the
system (SYS) up to 1A. The DC-to-SYS switch is a linear regulator designed to operate in dropout. This linear regulator prevents the SYS voltage from exceeding
5.3V. As shown in Table 1, DC supports four different
current limits that are set with the PEN1, PEN2, and
USUS digital inputs. These current limits are ideally
suited for use with AC-to-DC wall adapters and USB
power. The operating voltage range for DC is 4.1V to
6.6V, but it can tolerate up to 14V without damage.
When the DC input voltage is below the undervoltage
threshold (V DCL , 4V typ), it is considered invalid.
Similarly, if the DC voltage is above the overvoltage
threshold (VDCH, 6.9V typ), it is considered invalid.
When the DC voltage is below the battery voltage, it is
considered invalid. The DC power input is disconnected when the DC voltage is invalid. As shown in Table 1,
when power is available at the DC input, it has priority
over the USB input. Bypass DC to ground with at least
a 4.7µF capacitor.
USB
MAX8671X
VUSBL
4.0V RISING (typ)
500mV HYST
USB
UNDERVOLTAGE
UOK
USB
OVERVOLTAGE
VUSBH
6.9V RISING (typ)
400mV HYST
AGND
Figure 3. USB Power-OK Logic
26
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
1.5V
IADPTR
For the selected value of RDISET, calculate the DC current limit (IDCLIM) as follows (Table 2, Figure 4):
1.5V
IDCLIM = 2000 ×
RDISET
To support USB power sources at the DC input, pull
PEN1 low. With PEN1 low, drive PEN2 and USUS to
select between three internally set USB-related current
limits as shown in Table 1. Choose 100mA for lowpower USB mode. Choose 500mA for high-power USB
mode. Choose suspend to reduce the DC current to
0.11mA (typ) for both USB suspend mode and unconfigured OTG mode. To comply with the USB 2.0 specification, each device must be initially configured for low
power. After USB enumeration, the device can switch
from low power to high power if given permission from
the USB host. When the load exceeds the current limit,
SYS drops below BAT by VBSREG and the battery supplies supplemental load current.
If the DC power input is not required, connect DC to
ground or leave it unconnected.
The MAX8671X reduces the USB and DC current limits
by 5%/°C when the die temperature exceeds +100°C.
The system load (ISYS) has priority over the charger current, so input current is first reduced by lowering charge
current. If the junction temperature still reaches +120°C
in spite of charge-current reduction, no input current is
drawn from USB and DC; the battery supplies the entire
load and SYS is regulated below BAT by VBSREG. Note
that this on-chip thermal-limiting circuit is not related to
and operates independently from the thermistor input.
DC Power-OK Output (DOK)
As shown in Figure 5, the DC power-OK output (DOK)
is an open-drain, active-low output. The DOK output
pulls low when the voltage from DC to AGND (VDC) is
between V DCH (typically 6.9V) and V DCL (typically
4.0V).
RDISET (kΩ)
IDCLIM (mA)
RDISET (kΩ)
IDCLIM (mA)
3.01
997
4.32
694
3.09
971
4.42
679
3.16
949
4.53
662
3.24
926
4.64
647
3.32
904
4.75
632
3.40
882
4.87
616
3.48
862
4.99
601
3.57
840
5.11
587
3.65
822
5.23
574
3.74
802
5.36
560
3.83
783
5.49
546
3.92
765
5.62
534
4.02
746
5.76
521
4.12
728
5.90
508
4.22
711
6.04
497
DC INPUT CURRENT LIMIT vs.
DC INPUT CURRENT-LIMIT RESISTOR
1000
PEN1 = HIGH
900
IDCLIM (mA)
RDISET ≥ 2000 ×
Table 2. DC Current Limit for Standard
Values of RDISET
800
700
600
500
3.0
3.5
4.0
4.5
5.0
5.5
6.0
RDISET (kΩ)
Figure 4. Programming DC Current Limit
The DC power-OK circuitry remains active in thermal
overload and DC suspend. If the DC power-OK output
feature is not required, connect DOK to ground or leave
disconnected.
______________________________________________________________________________________
27
MAX8671X
To support common 500mA to 1000mA wall adapters
at the DC input, pull PEN1 high. With PEN1 pulled high,
the DC current limit is set by an external resistor from
DISET to AGND (RDISET). Choose RDISET based on the
current capability of the AC-to-DC adapter (IADPTR) as
follows:
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
DC
MAX8671X
VDCL
4.0V RISING (TYP)
500mV HYST
USB
UNDERVOLTAGE
DOK
USB
OVERVOLTAGE
VDCH
6.9V RISING (TYP)
400mV HYST
AGND
Figure 5. DC Power-OK Logic
Battery Charger
Figure 6 shows the typical Li+/Li-Poly charge profile for
the MAX8671X, and Figure 7 shows the battery charger
state diagram.
With a valid DC and/or USB input, the battery charger
initiates a charge cycle when the charger is enabled. It
first detects the battery voltage. If the battery voltage is
less than the prequalification threshold (3.0V), the
charger enters prequalification mode in which the battery charges at 10% of the maximum fast-charge current while deeply discharged. Once the battery voltage
rises to 3.0V, the charger transitions to fast-charge
mode and applies the maximum charge current. As
charging continues, the battery voltage rises until it
approaches the battery regulation voltage (selected
with BVSET) where charge current starts tapering
down. When charge current decreases to 4% of the
maximum fast-charge current, the charger enters a
brief 15s top-off state and then charging stops. If the
battery voltage subsequently drops below the battery
regulation voltage by VBATRCHG, charging restarts and
the timers reset.
The battery charge rate is set by several factors:
• Battery voltage
• USB/DC input current limit
• Charge setting resistor, RCISET
The MAX8671X automatically reduces charge current
to prevent input overload. MAX8671X also reduces
charge current when in thermal regulation (see the
Thermal Limiting and Overload Protection section for
more information).
Battery Regulation Voltage (BVSET)
BVSET allows the maximum battery charge voltage to
be set to 4.1V, 4.2V, or 4.350V. Drive BVSET low to set
the regulation voltage to 4.1V. Connect BVSET to VL or
leave unconnected to set the regulation voltage to 4.2V.
Connect BVSET to AGND through a 45kΩ to 55kΩ
resistor (R BVSET ) to set the regulation voltage to
4.350V. RBVSET accuracy is not critical. A 51kΩ ±5%
resistor is acceptable.
Charge Enable Input (CEN)
CEN is a digital input. Driving CEN high disables the
battery charger. CEN does not affect the USB or DC
current limit. Driving USUS high also disables the battery charger when charging from a USB source (PEN1
= low).
In many systems, there is no need for the system
controller (typically a microprocessor (µP)) to disable
the charger because the MAX8671X independently
manages the charger power path. In these situations,
CEN can be connected to ground. Do not leave
CEN unconnected.
• System load (ISYS)
• Die temperature
28
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
FAST-CHARGE
(CONSTANT CURRENT)
FAST-CHARGE
(CONSTANT VOLTAGE)
TOP-OFF
MAX8671X
PREQUALIFICATION
DONE
BATTERY VOLTAGE
VBATREG
VBATPRQ
BATTERY
CHARGE CURRENT
ICHGMAX
IPQ
ITO
0
CST[1:2]
HIGH-Z
CST[1:2] = 11
LOW
CST[1:2] = 00
FOR SIMPLICITY, THIS FIGURE ASSUMES THAT ISYS ~ 0mA
Figure 6. Li+/Li-Poly Charge Profile
______________________________________________________________________________________
29
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
ICHGMAX = 2000 x
NO INPUT POWER
CST [1:2] = 11
UOK = 0, DOK = 0
ICHG = 0mA
1.5V
RCISET
USB AND DC = INVALID
USB AND/OR DC = INVALID
CHARGER DISABLED
CST[1:2] = 11
UOK AND/OR DOK = 1
ICHG = 0mA
THERMISTOR SUSPEND
ICHG = 0mA
CST[1:2] = 01
UOK AND/OR DOK = 1
ANY STATE
CEN = 1
OR
USUS = 1
CEN = 0
USUS = 0
IC SETS TIMER = 0
THM OUT OF RANGE
IC SUSPENDS TIMER
t > tPREQUAL
PREQUALIFICATION
CST[1:2] = 00
UOK AND/OR DOK = 1
ICHG = ICHGMAX/10
THM WITHIN RANGE
IC RESUMES TIMER
THERMISTOR SUSPEND
ICHG = 0mA
CST[1:2] = 01
UOK AND/OR DOK = 1
VBAT < 2.82V
IC SETS TIMER = 0
THM OUT OF RANGE
IC SUSPENDS TIMER
VBAT > 3.0V
IC SETS TIMER = 0
t > tFST-CHG
FAST-CHARGE
CST[1:2] = 00
UOK AND/OR DOK = 1
THM WITHIN RANGE
IC RESUMES TIMER
ICHG > ICHGMAX x 7%
IC SETS TIMER = 0
THM OUT OF RANGE
THERMISTOR SUSPEND
ICHG = 0mA
CST[1:2] = 01
UOK AND/OR DOK = 1
TIMER FAULT
CST [1:2] = 10
ICHG = 0mA
UOK AND/OR DOK = 1
ICHG < ICHGMAX x 4%
AND VBAT = 4.2V
IC SETS TIMER = 0
TOP-OFF
CST[1:2] = 11
UOK AND/OR DOK = 1
VBAT = VBATREG
t > 15s
THM WITHIN RANGE
t > 15s
ICHG < ICHGMAX x 53%
OR VBAT = VBATREG
IC RESUMES TIMER
DONE
CST[1:2] = 11
UOK AND/OR DOK = 1
(VBATREG + VBATRCHG) < VBAT ≤ VBATREG
ICHG = 0mA
ICHG < ICHGMAX x 50%
AND VBAT < VBATREG
IC EXTENDS TIMER BY 2x
TIMER EXTEND
CST [1:2] = 00
(ISET x 20%) < ICHG < (ICHGMAX x 50%)
VBAT <
(VBATREG + VBATRCHG)
IC SETS TIMER = 0
ICHG < ICHGMAX x 20%
AND VBAT < VBATREG
IC SUSPENDS TIMER
ICHG < ICHGMAX x 23%
AND VBAT = VBATREG
IC RESUMES TIMER
TIMER SUSPEND
CST [1:2] = 00
ICHG < (ICHGMAX x 20%)
Figure 7. Charger State Diagram
Charge Status Outputs (CST1, CST2)
CST1 and CST2 are open-drain charger status outputs.
Their function is shown in Table 3 and Figure 7. When
the MAX8671X is used with a µP, pull CST1 and CST2
up to the system logic voltage with resistors to indicate
30
charge status to the µP. Alternatively, CST1 and CST2
sink up to 20mA each for LED charge indicators.
If the charge status output feature is not required, connect
CST1 and CST2 to ground or leave them unconnected.
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Table 4. Charge Times vs. CCT
CCT (nF)
tPQ (min)
Prequalification or
fast charge
tFC (min)
100% to 50%
tFC (min)
50% to 20%
68
15.0
299
598
Thermistor suspend
100
22.0
440
880
No
Timer fault
150
33.0
660
1320
220
48.4
968
1936
No
No input power or
top-off or
done
470
103.4
2068
4136
CST1
CST2
CHARGING
STATE
0
0
Yes
0
1
No
1
1
0
1
Note: CST1 and CST2 are active-low, open-drain outputs. “0”
indicates that the output device is pulling low. “1” indicates
that the output is high impedance.
CHARGE, PREQUALIFICATION,
AND TOP-OFF CURRENT
vs. CHARGE SETTING RESISTOR
Charge Timer (CT)
CCT
0.15μF
CCT
tFC = 660 min ×
0.15μF
tPQ = 33 min ×
1000
ICHGMAX
CURRENT (mA)
As shown in Figure 7, a fault timer prevents the battery
from charging indefinitely. In prequalification and fastcharge modes, the timer is controlled by the capacitance at CT (CCT). The MAX8671X supports values of
CCT from 0.01µF to 1µF. Calculate the prequalification
and fast-charge times as follows (Table 4, Figure 8):
100
IPQ
ITO
10
1
0
When the charger exits fast-charge mode, a fixed 15s
top-off mode is entered:
t TO = 15s
While in the constant-current fast-charge mode (Figure
6), if the MAX8671X reduces the battery charge current
due to its internal die temperature or large system
loads, it slows down the charge timer. This feature eliminates nuisance charge timer faults. When the battery
charge current is between 100% and 50% of its programmed fast-charge level, the fast-charge timer runs
at full speed. When the battery charge current is
between 50% and 20% of the programmed fast-charge
level, the fast-charge timer is slowed by 2x. Similarly,
when the battery charge current is below 20% of the
programmed fast-charge level, the fast-charge timer is
paused. The fast-charge timer is not slowed or paused
when the charger is in the constant voltage portion of
its fast-charge mode (Figure 6) where charge current
reduces normally.
5
10
15
RCISET (kΩ)
Figure 8. Programming Charge Current
Connect CT to AGND to disable the prequalification
and fast-charge timers. With the internal timers of the
MAX8671X disabled, an external device, such as a µP,
can control the charge time through the CEN input.
Setting the Charger Currents (CISET)
As shown in Table 5 and Figure 9, a resistor from
CISET to ground (R CISET ) sets the maximum fastcharge current (ICHGMAX), the charge current in prequalification mode (IPQ), and the top-off threshold (ITO).
The MAX8671X supports values of I CHGMAX from
200mA to 1000mA. Select the RCISET as follows:
RCISET = 2000 ×
1.5V
ICHGMAX
______________________________________________________________________________________
31
MAX8671X
Table 3. Charge Status Outputs
Table 5. Ideal Charge Currents vs.
Charge Setting Resistor
MONITORING THE BATTERY CHARGE
CURRENT WITH VCISET
RCISET (kΩ)
ICHGMAX (mA)
IPQ (mA)
ITO (mA)
3.01
1000
100
40
4.02
746
75
30
4.99
601
60
24
6.04
497
50
20
6.98
430
43
17
8.06
372
37
15
9.09
330
33
13
10.0
300
30
12
11.0
273
27
11
12.1
248
25
10
13.0
231
23
9
14.0
214
21
9
15.0
200
20
8
VCISET =
VCISET (V)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
RCISET
x IBAT
2000
1.5
0
DISCHARGING
1.5V
2000 x R
CISET
0
BATTERY CHARGING CURRENT (A)
Figure 9. Monitoring the Battery Charge Current with the
Voltage from CISET to AGND
Determine ICHGMAX by considering the characteristics
of the battery. It is not necessary to limit the charge current based on the capabilities of the expected AC-toDC adapter or USB charging input, the system load, or
thermal limitations of the PCB. The MAX8671X automatically lowers the charging current as necessary to
accommodate these factors.
For the selected value of RCISET, calculate ICHGMAX,
IPQ, and ITO as follows:
ICHGMAX = 2000 ×
1.5V
RCISET
IPQ = 10% × ICHGMAX
ITO = 4% × ICHGMAX
In addition to setting the charge current, CISET also provides a means to monitor battery charge current. The
CISET output voltage tracks the charge current delivered
to the battery, and can be used to monitor the charge
rate, as shown in Figure 9. A 1.5V output indicates the
battery is being charged at the maximum set fast-charge
current, and 0V indicates no charging. This voltage is
also used by the charger control circuitry to set and
monitor the battery current. Avoid adding capacitance
32
directly to the CISET pin that exceeds 10pF. If filtering of
the charge current monitor is necessary, include a resistor of 100kΩ or more between CISET and the filter
capacitor to preserve charger stability.
Step-Down Converters
(REG1, REG2, REG3)
REG1, REG2, and REG3 are high-efficiency 2MHz current-mode, step-down converters with adjustable outputs. Each REG1, REG2, and REG3 step-down
converter delivers at least 425mA.
The step-down regulator power inputs (PV_) must be
connected to SYS. The step-down regulators operate
with V SYS from 2.6V to 5.5V. Undervoltage lockout
ensures that the step-down regulators do not operate
with SYS below 2.6V (typ).
See the Enable/Disable (EN) and Sequencing section
for how to enable and disable the step-down converters. When enabled, the MAX8671X gradually ramps
each output up during a soft-start time. Soft-start eliminates input current surges when regulators are
enabled.
See the PWM section for information about the stepdown converters control scheme.
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
⎛V
⎞
RFBH = RFBL × ⎜ OUT − 1⎟
⎝ 1.0V
⎠
REG1, REG2, and REG3 are optimized for high, medium, and low output voltages, respectively. The highest
overall efficiency occurs with V1 set to the highest output voltage and V3 set to the lowest output voltage.
PWM
The MAX8671X operates in either auto-PWM or forcedPWM modes. At light load, auto PWM switches only as
needed to supply the load to improve light-load efficiency of the step-down converter. At higher load currents (~100mA), the step-down converter transitions to
fixed 2MHz switching. Forced PWM always operates
with a constant 2MHz switching frequency regardless
of the load. This is useful in low-noise applications.
Permanently connect PWM high for forced-PWM applications or low for auto-PWM applications. Do not
change PWM on-the-fly.
Step-Down Dropout and Minimum Duty Cycle
All the step-down regulators are capable of operating
in 100% duty-cycle dropout; however, REG1 has been
optimized for this mode of operation. During 100%
duty-cycle operation, the high-side p-channel MOSFET
turns on constantly, connecting the input to the output
through the inductor. The dropout voltage (VDO) is calculated as follows:
VDO = ILOAD (RP + RL)
where:
RP = p-channel power switch RDS(ON)
RL = external inductor ESR
The minimum duty cycle for all step-down regulators is
12.5% (typ), allowing a regulation voltage as low as 1V
over the full SYS operating range. REG3 is optimized
for low duty-cycle operation.
Step-Down Input Capacitors
The input capacitor in a step-down converter reduces
current peaks drawn from the power source and
reduces switching noise in the controller. The impedance of the input capacitor at the switching frequency
must be less than that of the source impedance of the
supply so that high-frequency switching currents do not
pass through the input source.
The step-down regulator power inputs are critical discontinuous current paths that require careful bypassing. In the PCB layout, place the step-down regulator
input bypass capacitors as close as possible to each
pair of switching regulator power input pins (PV_ to
PG_) to minimize parasitic inductance. If making connections to these caps through vias, be sure to use
multiple vias to ensure that the layout does not insert
excess inductance or resistance between the bypass
cap and the power pins.
The input capacitor must meet the input ripple current
requirement imposed by the step-down converter.
Ceramic capacitors are preferred due to their low ESR
and resilience to power-up surge currents. Choose the
input capacitor so that its temperature rise due to input
ripple current does not exceed about +10°C. For a
step-down DC-DC converter, the maximum input ripple
current is half of the output current. This maximum input
ripple current occurs when the step-down converter
operates at 50% duty factor (VIN = 2 x VOUT).
Bypass each step-down regulator input with a 4.7µF
ceramic capacitor from PV_ to PG_. Use capacitors
that maintain their capacitance over temperature and
DC bias. Ceramic capacitors with an X7R or X5R temperature characteristic generally perform well. The
capacitor voltage rating should be 6.3V or greater.
Step-Down Output Capacitors
The output capacitance keeps output ripple small and
ensures control loop stability. The output capacitor
must have low impedance at the switching frequency.
Ceramic, polymer, and tantalum capacitors are suitable, with ceramic exhibiting the lowest ESR and lowest
high-frequency impedance. The MAX8671X requires at
least 20µF of output capacitance, which is best
achieved with two 10µF ceramic capacitors in parallel.
As the case sizes of ceramic surface-mount capacitors
decrease, their capacitance vs. DC bias voltage characteristic becomes poor. Due to this characteristic, it is
possible for 0805 capacitors to perform well while 0603
capacitors of the same value might not. The MAX8671X
requires a nominal output capacitance of 20µF; however, after their DC bias voltage derating, the output
capacitance must be at least 15µF.
______________________________________________________________________________________
33
MAX8671X
The MAX8671X uses external resistor-dividers to set the
step-down output voltages between 1V and VSYS. Use at
least 10µA of bias current in these dividers to ensure no
change in the stability of the closed-loop system. To set
the output voltage, select a value for the resistor connected between FB_ and AGND (RFBL). The recommended value is 100kΩ. Next, calculate the value of the
resistor connected from FB_ to the output (RFBH):
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Step-Down Inductor
Choose the step-down regulator inductance to be
4.7µH. The minimum recommended saturation current
requirement is 600mA. In PWM mode, the peak inductor currents are equal to the load current plus one half
of the inductor ripple current. The MAX8671X works
well with physically small inductors. See Table 6 for
suggested inductors.
The peak-to-peak inductor ripple current during PWM
operation is calculated as follows:
V
(V
− VOUT )
IP−P = OUT SYS
VSYS × fS × L
where:
VOUT = output voltage
IOUTTAR = target (desired) output current—cannot
be more than the minimum p-channel current-limit
threshold
RN = n-channel on-resistance
RP = p-channel on-resistance
RL = external inductor’s ESR
VIN = input voltage—MAXIMUM
2) Use the following equation to calculate the maximum
output current (IOUTMAX):
(1 − D)
V
ILIM − OUT
2 × f ×L
IOUTMAX =
1− D
1+ (RN + RL )
2 × f ×L
where fS is the 2MHz switching frequency.
The peak inductor current during PWM operation is calculated as follows:
I
IL _ PEAK = ILOAD + P−P
2
where:
ILIM = p-channel current-limit threshold—MINIMUM
VOUT = output voltage
D = approximate duty cycle derived from step 1
Step-Down Converter Output Current
The three MAX8671X step-down regulators each provide at least 425mA of output current when using a recommended inductor (Table 6). To calculate the
maximum output current for a particular application and
inductor use the following two-step process (as shown
in Figure 10):
1) Use the following equation to calculate the approximate duty cycle (D):
f = oscillator frequency—MINIMUM
L = external inductor’s inductance—MINIMUM
RN = n-channel on-resistance
RL = external inductor’s ESR
V
+I
(R + RL )
D = OUT OUTTAR N
VIN + IOUTTAR (RN − RP )
Table 6. Suggested Inductors
MANUFACTURER
Sumida
Taiyo Yuden
TDK
TOKO
34
SERIES
INDUCTANCE
(µH)
ESR (Ω)
CURRENT RATING
(mA)
DIMENSIONS (mm)
CDRH2D11HP
4.7
190
750
3.0 x 3.0 x 1.2 = 10.8mm3
CDH2D09
4.7
218
700
3.0 x 3.0 x 1.0 = 9.0mm3
NR3012
4.7
130
770
3.0 x 3.0 x 1.2 = 10.8mm3
NR3010
4.7
190
750
3.0 x 3.0 x 1.0 = 9.0mm3
VLF3012
4.7
160
740
2.8 x 2.6 x 1.2 = 8.7mm3
VLF3010
4.7
240
700
2.8 x 2.6 x 1.0 = 7.3mm3
DE2812C
4.7
130
880
3.0 x 2.8 x 1.2 = 10.8mm3
DE2810C
4.7
180
640
3.0 x 2.8 x 1.0 = 8.4mm3
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
MAX8671X
TO FIND THE MAXIMUM OUTPUT CURRENT FOR REG3 WITH VIN = 3.2V TO 5.3V, VOUT = 1.2V, L = 4.7μH
±20%, AND RL = 130mΩ :
V
+I
(R + RL ) 1.2V + 0.425A(0.12Ω + 0.13Ω)
= 0.249
D = OUT OUTTAR N
=
VIN + IOUTTAR (RN − RP )
5.3V + 0.425A(0.12Ω − 0.23Ω)
1.2V(1− 0.249)
V
(1− D)
0.555A −
ILIM − OUT
6 Hz) × (4.7 × 10 −6 H × 0.8)
2
×
(
1
.
8
×
10
2 × f ×L
= 0.482A
IOUTMAX =
=
1− D
1− 0.249
1+ (RN + RL )
1+ (0.12Ω + 0.13Ω)
2 × f ×L
2 × (1.8 × 106Hz) × (4.7 × 10−6 H × 0.8)
Figure 10. Step-Down Converter Maximum Output Current Example
Linear Regulators (REG4, REG5)
The REG4 and REG5 linear regulators have low quiescent current, and low output noise. Each regulator supplies up to 180mA to its load. Bypass each LDO output
with a 2.2µF or greater capacitor to ground. If V4 or V5
is set to less than 1.5V, bypass the output with 3.3µF or
greater.
Each linear regulator has an independent power input
(PV4 and PV5) with an input voltage range from 1.7V to
VSYS (VSYS can be up to 5.5V). Voltages below the
input undervoltage lockout threshold (1.6V) are invalid.
The regulator inputs can be driven from an efficient
low-voltage source, such as a DC-DC output, to optimize efficiency (see the following equation). Bypass
each LDO input with a 1µF or greater capacitor to
ground:
V
EfficiencyLDO ≈ OUT
VIN
REG5 is intended to power the system USB transceiver
circuitry and is only active when USB power is available. REG4 is powered from the battery when power is
not available at DC or USB.
See the Enable/Disable (EN) and Sequencing section
for how to enable and disable the linear regulators.
When enabled, the linear regulators soft-start by ramping their outputs up to their target voltage in 3ms. Softstart limits the inrush current when the regulators are
enabled.
The MAX8671X uses external resistor-dividers to set
the LDO output voltages between 0.6V and VPV_. Use
at least 10µA of bias current in these dividers to ensure
no change in the stability of the closed-loop system. To
set the output voltage, select a value for the resistor
connected between FB_ and AGND (RFBL). The recom-
mended value is 60.4kΩ. Next, calculate the value of
the resistor connected from FB_ to the output (RFBH):
⎛V
⎞
RFBH = RFBL × ⎜ OUT − 1⎟
⎝ 0.6V
⎠
For REG4, an external 0.01µF bypass capacitor from
BP to AGND in conjunction with a 150kΩ internal resistor creates a 110Hz lowpass filter for noise reduction.
BP is a high-impedance node and requires a low-leakage capacitor. For example, a leakage of 40nA results
in a 1% error.
VL Linear Regulator
VL is the output of a 3.3V linear regulator that powers
MAX8671X internal circuitry. VL is internally powered
from the higher of USB or DC and automatically powers
up when either of these power inputs exceeds approximately 1.5V. When the higher of the DC and USB supply is between 1.5V and 3.3V, VL operates in dropout.
VL automatically powers down when both the USB and
DC power inputs are removed. Bypass VL to AGND
with a 0.1µF capacitor.
VL remains on even when USB and/or DC are in overvoltage or undervoltage lockout, when SYS is in undervoltage lockout, and also during thermal faults.
VL sources up to 3mA for external loads. If VL is not
used for external loads, the MAX8671X’s USB/DC current limit guarantees compliance with the USB 2.0 input
current specifications. If VL is used for external loads,
USB/DC currents increase and might exceed the limits
outlined in the USB 2.0 specification. For example, if the
USB to SYS current is limited to 95mA and VL is sourcing 3mA, IUSB is 98mA. Similarly, if the USB input is suspended and VL is sourcing 3mA, IUSB is 3mA.
______________________________________________________________________________________
35
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
SYS
SYSOK
2.5V FALLING
100mV HYST
PV4
DIE TEMP
MAX8671X
PV4OK
1.6V RISING
100mV HYST
PV5
DT165
+165°C
PV5OK
SOFT-START
1.6V RISING
100mV HYST
USB
REG3
USBOVLO
6.9V RISING
400mV HYST
REGON
OK
EN
REG3OK
USBPOK
SOFT-START
USBUVLO
REG1
4.0V RISING
500mV HYST
REGON
REG3OK
DC
DCOVLO
6.9V RISING
400mV HYST
OK
EN
REG1OK
SOFT-START
DCPOK
REG2
OK
EN
DCUVLO
REG2OK
4.0V RISING
500mV HYST
SOFT-START
EN
REGON
2MHz
OSC
REG1OK
BIAS
&
REF
REG4
REG3OK
OK
EN
REG4OK
REG2OK
DT165
PV4OK
SYSOK
SOFT-START
64 CYCLE
DELAY
(32ms)
REGON
REGON
REG5
REG3OK
REG1OK
EN
OK
REG5OK
REG2OK
REG4OK
PV5OK
Figure 11. Enable/Disable Logic
Enable/Disable (EN) and Sequencing
Figures 11, 12, and 13 show how the five MAX8671X
regulators are enabled and disabled. With a valid SYS
voltage and die temperature, asserting EN high
enables REG1–REG4. Pulling EN low disables
36
REG1–REG5. REG5 is intended to power the system
USB transceiver circuitry, which is only active when
USB power is available. Therefore, a valid source must
be on either the USB or DC input for REG5 to enable.
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
MAX8671X
VDC
VUSB
VVL
VBAT < VSYS < (VUSB OR VDC)
VSYS
VBAT
VBAT
tD1
VEN
tSS1
VOUT1
tSS2
VOUT2
tD2
tSS3
VOUT3
tD3
tSS4
VOUT4
tSS5
VOUT5
VUOK
VDOK
INTERNAL
DISCHARGE
RESISTORS
HIGH-Z
HIGH-Z
HIGH-Z
HIGH-Z
Figure 12. Enable and Disable Waveforms
The VL regulator is not controlled by EN. It is powered
from the higher of USB or DC and automatically powers
up when either of the power inputs exceeds approximately 1.5V. Similarly, VL automatically powers down
when both the USB and DC power inputs are removed.
Soft-Start/Inrush Current
ages, and to fully comply with the USB 2.0 specifications. All USB, DC, and charging functions implement
soft-start. The USB and DC nodes only require 4.7µF of
input capacitance. Furthermore, all regulators implement soft-start to avoid transient overload of power
inputs (Figure 12).
The MAX8671X implements soft-start on many levels to
control inrush current, to avoid collapsing supply volt______________________________________________________________________________________
37
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Active Discharge in Shutdown
Each MAX8671X regulator (REG1–REG5) has an internal 1kΩ resistor that discharges the output capacitor
when the regulator is off. The discharge resistors
ensure that the load circuitry powers down completely.
The internal discharge resistors are connected when a
regulator is disabled and when the device is in UVLO
with an input voltage greater than 1.0V. With an input
voltage less than 1.0V, the internal discharge resistors
are not activated.
Undervoltage and Overvoltage Lockout
USB/DC UVLO
Undervoltage lockout (UVLO) prevents an input supply
from being used when its voltage is below the operat-
ing range. When the USB voltage is less than the USB
UVLO threshold (4.0V typ), the USB input is disconnected from SYS, and UOK goes high impedance.
When the DC voltage is less than the DC UVLO threshold (4.0V typ), the DC input is disconnected from SYS,
and DOK goes high impedance. In addition, when both
USB and DC are in UVLO, the battery charger is disabled, and BAT is connected to SYS through the internal system load switch. REG1–REG4 are allowed to
operate from the battery without power at USB or DC.
REG5 is intended to power the system USB transceiver
circuitry, which is only active when USB power is available. Therefore, a valid source must be present on
either the USB or DC input for REG5 to enable.
UNPLUGGING USB WITH NOTHING TO DISCHARGE CUSB (VBAT = 3.3V). V5 SET FOR 3.3V
UNPLUG
EVENT
5V
RAPID DISCHARGE UNTIL VUSB DECAYS
TO THE HIGHER OF 3.5V OR VBAT + 5OmV
VUSB
3.5V
SLOW DISCHARGE AS THE MAX8671X
DRAWS USB QUIESCENT CURRENT
HIGH-Z
VUOK
tDDREG5 = 120μs (typ)
V5
IF VBAT ≥ 3.4V, VPV5 WILL REGULATE TO 3.3V
IF VBAT ≤ 3.4V, VPV5 WILL BE SLIGHTLY LESS
THAN VBAT (DROPOUT)
Figure 13. REG5 Disable Detail
38
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
SYS UVLO
A UVLO circuit monitors the voltage from SYS to
ground (VSYS). When VSYS falls below VUVLO_SYS (2.5V
typ), REG1–REG5 are disabled. V UVLO_SYS has a
100mV hysteresis. The VL supply remains active in SYS
UVLO.
REG4/REG5 UVLO
A UVLO circuit monitors the PV4 and PV5 LDO power
inputs. When the PV_ voltage is below 1.6V, it is invalid
and the LDO is disabled.
Thermal Limiting and Overload Protection
The MAX8671X is packaged in a 5mm x 5mm x 0.8mm
40-pin thin QFN. Table 7 shows the thermal characteristics of this package. The MAX8671X has several
mechanisms to control junction temperature in the
event of a thermal overload.
Table 7. 5mm x 5mm x 0.8mm Thin QFN
Thermal Characteristics
SINGLE-LAYER PCB
MULTILAYER PCB
1777.8mW
2857.1mW
*θJA
Derate 22.2mW/°C
above +70°C
45°C/W
Derate 35.7mW/°C
above +70°C
28°C/W
θJC
1.7°C/W
1.7°C/W
Continuous
Power
Dissipation
Smart Power Selector Thermal-Overload Protection
The MAX8671X reduces the USB and DC current limits
by 5%/°C when the die temperature exceeds +100°C.
The system load (ISYS) has priority over the charger
current, so input current is first reduced by lowering
charge current. If the junction temperature still reaches
+120°C in spite of charge-current reduction, no input
current is drawn from USB and DC; the battery supplies
the entire load and SYS is regulated 82mV (VBSREG)
below BAT. Note that this on-chip thermal-limiting circuit is not related to and operates independently from
the thermistor input.
Regulator Thermal-Overload Shutdown
The MAX8671X disables all regulator outputs (except
VL) when the junction temperature rises above +165°C,
allowing the device to cool. When the junction temperature cools by approximately 15°C, the regulators
resume the state indicated by the enable input (EN)
by repeating their soft-start sequence. Note that this
thermal-overload shutdown is a fail-safe mechanism;
proper thermal design should ensure that the junction
temperature of the MAX8671X never exceeds the
absolute maximum rating of +150°C.
Battery Charger Thermistor Input (THM)
The THM input connects to an external negative temperature coefficient (NTC) thermistor to monitor battery
or system temperature. Charging is suspended when
the thermistor temperature is out of range. Additionally,
the charge timers are suspended and charge status
indicators report that the charger is in thermistor suspend (CST[1:2] = 01). When the thermistor comes back
into range, charging resumes and the charge timer
continues from where it left off. Table 8 shows THM
temperature limits for various thermistor material constants. If the battery temperature monitor is not
required, bias THM midway between VL and AGND
with a resistive divider—100kΩ ±5% resistors are recommended. Biasing THM midway between V L and
AGND bypasses this function.
*θJA is specified according to the JESD51 standard.
______________________________________________________________________________________
39
MAX8671X
USB/DC OVLO
Overvoltage lockout (OVLO) prevents an input supply
from being used when its voltage exceeds the operating range. Both USB and DC withstand input voltages
up to 14V. When the USB voltage is greater than the
USB OVLO threshold (6.9V typ), the USB input is disconnected from SYS, and UOK goes high impedance.
When the DC voltage is greater than the DC OVLO
threshold (6.9V typ), the DC input is disconnected from
SYS, and DOK goes high impedance. In addition, when
both DC and USB are in OVLO, the battery charger is
disabled, and BAT is connected to SYS through the
internal system load switch. REG1–REG4 are allowed to
operate from the battery when USB and DC are in overvoltage lockout. The VL supply remains active in OVLO.
REG5 is intended to power the system USB transceiver
circuitry, which is only active when USB power is available. A valid source must be present on either the USB
or DC input for REG5 to enable.
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Table 8. Trip Temperatures for Different Thermistors
3000
3250
3500
3750
4250
4250
RTB (kΩ)
THERMISTOR BETA (ß [K])
10
10
10
10
10
10
RTP (kΩ)
Open
Open
Open
Open
Open
120
RTS (kΩ)
Short
Short
Short
Short
Short
Short
Resistance at +25°C [kΩ]
10
10
10
10
10
10
Resistance at +50°C [kΩ]
4.59
4.30
4.03
3.78
3.32
3.32
Resistance at 0°C [kΩ]
25.14
27.15
29.32
31.66
36.91
36.91
Nominal Hot Trip
Temperature [°C]
55
53
51
49
46
45
Nominal Cold Trip
Temperature [°C]
-3
-1
0
2
5
0
VL
CEN
RTB
0.74 x VL
ALTERNATE THERMISTOR
CONFIGURATION
COLD
THM
TEMPERATURE
SUSPEND
HOT
0.284 x VL
RTS
T
RTP
ESD
DIODE
T
AGND
BOTH COMPARATORS
HAVE 65mV HYSTERESIS
MAX8671X
Figure 14. Thermistor Input
Since the thermistor monitoring circuit employs an
external bias resistor from THM to VL (RTB in Figure
14), any resistance thermistor can be used as long as
the value of RTB is equivalent to the thermistor’s +25°C
resistance. For example, with a 10kΩ at +25°C thermistor, use 10kΩ at RTB, and with a 100kΩ at +25°C thermistor, use 100kΩ at R TB . The general relation of
thermistor resistance to temperature is defined by the
following equation:
⎧ ⎛
1
1 ⎞⎫
RT = R25 × e⎨β⎜
−
⎟⎬
⎝
⎠⎭
T
+
273
298
⎩
40
where:
RT = The resistance in ohms of the thermistor at temperature T in Celsius
R 25 = The resistance in ohms of the thermistor at
+25°C
β = The material constant of the thermistor that typically
ranges from 3000K to 5000K
T = The temperature of the thermistor in °C that corresponds to RT
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
PCB Layout and Routing
Good printed circuit board (PCB) layout is necessary to
achieve optimal performance. Refer to the MAX8671
evaluation kit for Maxim’s recommended layout.
Use the following guidelines for the best results:
• Use short and wide traces for high-current and discontinuous current paths.
• The step-down regulator power inputs are critical
discontinuous current paths that require careful
bypassing. Place the step-down regulator input
bypass capacitors as close as possible to each
switching regulator power input pair (PV_ to PG_).
• Minimize the area of the loops formed by the stepdown converters’ dynamic switching currents.
• The exposed paddle (EP) is the main path for heat
to exit the IC. Connect EP to the ground plane with
thermal vias to allow heat to dissipate from the
device.
• The MAX8671X regulator feedback nodes are sensitive high-impedance nodes. Keep these nodes as
short as possible and away from the inductors.
• The thermistor node is high impedance and should
be routed with care.
• Make power ground connections to a power ground
plane. Make analog ground connections to an analog ground plane. Connect the ground planes at a
single point.
MAX8671X
THM threshold adjustment can be accommodated by
changing RTB, connecting a resistor in series and/or in
parallel with the thermistor, or using a thermistor with different material constant (β). For example, a +45°C hot
threshold and 0°C cold threshold can be realized by
using a 10kΩ thermistor with a β of 4250K and connecting 120kΩ in parallel. Since the thermistor resistance
near 0°C is much higher than it is near +50°C, a large
parallel resistance lowers the cold threshold, while only
slightly lowering the hot threshold. Conversely, a small
series resistance raises the cold threshold, while only
slightly raising the hot threshold. Raising RTB lowers
both the hot and cold thresholds, while lowering RTB
raises both thresholds.
TOP VIEW
8671XE
TLyww
+ aaaa
THIN QFN
5mm x 5mm x 0.8mm
Figure 15. Package Marking Example
• The REG4 LDO is a high-performance LDO with
high PSRR and low noise and care should be used
in the layout to obtain the high performance.
Generally, the REG4 LDO is powered from a stepdown regulator output, and therefore, its input
capacitor should be bypassed to the power ground
plane. However, its output capacitor should be
bypassed to the analog ground plane.
• BP is a high impedance node and leakage current
into or out of BP can affect the LDO output accuracy.
Package Marking
The top of the MAX8671X package is laser etched as
shown in Figure 15:
• “8671XETL” is the product identification code. The
full part number is MAX8671XETL; however, in this
case, the “MAX” prefix is omitted due to space
limitations.
• “yww” is a date code. “y” is the last number in the
Gregorian calendar year. “ww” is the week number
in the Gregorian calendar. For example:
“801” is the first week of 2008; the week of
January 1st, 2008
“052” is the fifty-second week of 2010; the
week of December 27th, 2010.
“aaaa” is an assembly code and lot code.
“+” denotes lead-free packaging and marks
the pin 1 location.
Chip Information
PROCESS: BiCMOS
______________________________________________________________________________________
41
PWM
PV1
LX1
PG1
PG3
LX3
PV3
VL
FB3
TOP VIEW
DISET
Pin Configuration
30 29 28 27 26 25 24 23 22 21
20 EN
CISET 31
19 FB1
CT 32
THM 33
18 AGND
BAT 34
17 BVSET
16 PV4
SYS 35
MAX8671X
PEN1 36
15 OUT4
CST2 37
14 BP
UOK 38
13 FB4
12 DOK
EXPOSED PADDLE (EP)
+
4
5
6
7
8
9
10
OUT5
PG2
LX2
PV2
CEN
3
FB5
2
PV5
11 FB2
1
DC
PEN2 40
USB
CST1 39
USUS
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
THIN QFN
5mm x 5mm x 0.8mm
42
______________________________________________________________________________________
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
QFN THIN.EPS
______________________________________________________________________________________
43
MAX8671X
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
MAX8671X
PMIC with Integrated Charger and
Smart Power Selector for Handheld Devices
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
44 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2007 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products. Inc.
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