MP2690
All-in-One, 2.5A Battery Charger
with 2.1A Boost Current
DESCRIPTION
FEATURES
The MP2690 is a highly integrated, flexible,
switch-mode battery charger with system powerpath management and is designed for single-cell
Li-ion or Li-polymer battery use in a wide range
of applications.
The IC can operate in both charge mode and
boost mode to allow for full system and battery
power management.
The IC has an integrated IN-to-SYS pass-through
path to pass the input voltage to the system. The
pass-through path has built-in over-voltage and
over-current protection and has a higher priority
over the charging path.
When the input power is present, the device
operates in charge mode. The MP2690 detects
the battery voltage automatically and charges the
battery in three phases: trickle current, constant
current, and constant voltage. Other features
include charge termination and auto-recharge.
The MP2690 also integrates both input current
limit and input voltage regulation to manage input
power and meet the priority of the system power
demand.
In the absence of an input source, the IC
switches to boost mode through PB to power
SYS from the battery. In boost mode, OLIM
programs the output current limit, and the IC
turns off at light load automatically. The IC also
uses output short-circuit protection to disconnect
the battery from the load completely in the event
of a short-circuit fault. The MP2690 resumes
normal operation once the short-circuit fault is
removed.
The 4-LED driver is integrated for voltage-based
fuel gauge indication. Together with torch-light
control, the MP2690 provides an all-in-one
solution for power banks and similar applications
without an external micro-controller.
Up to 14V Sustainable Input Voltage
4.65V to 6V Operating Input Voltage Range
Power Management Function, Integrated
Input Current Limit, Input Voltage Regulation
Up to 2.5A Programmable Charge Current
Trickle-Charge Function
Selectable 4.2V/4.35V/4.45V Charge Voltage
with 0.5% Accuracy
4-LED Driver for Battery Fuel Gauge
Indication
Automatic Turn-Off at Light Load
Input Source Detection
Output Source Signaling
Torch-Light Control
Negative Temperature Coefficient Pin for
Battery Temperature Monitoring
Programmable Timer Back-Up Protection
Thermal Regulation and Thermal Shutdown
Internal Battery Reverse Leakage Blocking
Integrated Over-Voltage Protection (OVP)
and Over-Current Protection (OCP) for PassThrough Path
Reverse Boost Operation Mode for System
Power
Up to 2.1A Programmable Output Current
Limit for Boost Mode
Integrated Short-Circuit Protection (SCP) and
Output Over-Voltage Protection for Boost
Mode
APPLICATIONS
Sub-Battery Applications
Power-Bank Applications for Smart Phones
Tablets and Other Portable Devices
All MPS parts are lead-free, halogen-free, and adhere to the RoHS
directive. For MPS green status, please visit the MPS website under
Quality Assurance. “MPS” and “The Future of Analog IC Technology” are
registered trademarks of Monolithic Power Systems, Inc.
Analog digital adaptive modulation (ADAM) is a trademark of Monolithic
Power Systems, Inc.
The MP2690 is available in a 26-pin QFN
(4mmx4mm) package.
.
MP2690 Rev.1.0
6/24/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
1
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
TYPICAL APPLICATION
USB OUTPUT
C2 CSYS
USB INPUT
PB
SYS
DM2
5V Input
DP2
SW
RS1
L1
ICHG
IBATT
VIN
CIN
Q1
Q2
Q3
CBATT
CSP
Battery
Q4
DM1
BATT
VBATT
VNTC
DP1
NTC
VNTC
MP2690
TC
VBATT
VCC
C4
LED1
VB
LED2
ILIM
LED3
OLIM
LED4
ISET
AGND
PGND
VCC
TMR
CTMR
RILIM ROLIM RISET
Table 1: Operation Mode Control
VIN (V)
PB
VBATT + 300mV < VIN < 6V
VIN > 6V
X
From H to L
for >1.5ms
X
Operation
Mode
Charging
Discharging
(boost)
OVP
VIN < 2V
H or L
Sleep
VIN < VBATT + 300mV
MP2690 Rev.1.0
6/24/2016
Q1, Q2
Q3
Q4
On
SW
SW
Off
SW
SW
Off
Off
Off
Off
Off
Off
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2
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
ORDERING INFORMATION
Part Number*
Package
Top Marking
MP2690GR
QFN-26 (4mmx4mm)
See Below
* For Tape & Reel, add suffix –Z (e.g. MP2690GR–Z)
TOP MARKING
MPS: MPS prefix
Y: Year code
WW: Week code
MP2690: Product code of MP2690GR
LLLLLL: Lot number
PACKAGE REFERENCE
TOP VIEW
LED1
26
PGND
SW
25
24
23
22
21
VB
20
1
19
NTC
18
VNTC
17
AGND
16
VCC
15
OLIM
14
ISET
13
TMR
2
SYS
3
SYS
4
VIN
LED2 LED3 LED4 CSP BATT
5
6
7
8
DM1
DP1
TC
9
10
11
ILIM DM2 DP2
12
PB
QFN-26 (4mmx4mm)
MP2690 Rev.1.0
6/24/2016
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3
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
(4)
θJA
θJC
ABSOLUTE MAXIMUM
RATINGS (1)
Thermal Resistance
VIN to PGND ............................... -0.3V to +14V
SYS to PGND ............................. -0.3V to +6.5V
SW to PGND ........-0.3V (-2V for 20ns) to +6.5V
BATT to PGND………………. ..... -0.3V to +6.5V
All other pins to AGND ................ -0.3V to +6.5V
(2)
Continuous power dissipation (TA = +25°C)
................................................................2.84W
Junction temperature……………………… 150°C
Lead temperature (solder)……………… .. 260°C
Storage temperature……… ..... -65°C to +150°C
NOTES:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ (MAX), the junction-toambient thermal resistance θJA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD (MAX) = (TJ
(MAX)-TA)/θJA. Exceeding the maximum allowable power
dissipation produces an excessive die temperature, causing
the regulator to go into thermal shutdown. Internal thermal
shutdown circuitry protects the device from permanent
damage.
3) The device is not guaranteed to function outside of its
operating conditions.
4) Measured on JESD51-7, 4-layer PCB.
Recommended Operating Conditions
QFN-26 (4mmx4mm)..............44 ........ 9 .... °C/W
(3)
Supply voltage (VIN) ...................... 4.65V to +6V
IIN ...................................................... Up to 2.7A
ISYS .................................................... Up to 2.1A
ICHG ................................................... Up to 2.5A
VBATT ............................................... Up to 4.45V
Operating junction temp. (TJ) ... -40°C to +125°C
MP2690 Rev.1.0
6/24/2016
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4
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
ELECTRICAL CHARACTERISTICS
VIN = 5.0V, RS1 = 10mΩ, TA = +25°C, unless otherwise noted.
Parameter
Symbol
Condition
IN-to-SYS NMOS on resistance
High-side PMOS on resistance
Low-side NMOS on resistance
RIN to SYS
RH_DS
RL_DS
High-side PMOS peak current
limit
IPEAK_HS
VCC = 5V
VCC = 5V
VCC = 5V
CC charge mode/boost mode
TC charge mode
Low-side NMOS peak current
limit
Max
Units
5.7
1.9
65
35
35
7
2.3
8.4
2.8
mΩ
mΩ
mΩ
A
A
IPEAK_LS
6.4
8
9.6
A
Switching frequency
VCC UVLO
VCC UVLO hysteresis
Charge Mode
Fsw
VCC_UVLO
500
1.96
600
2.16
100
800
2.36
kHz
V
mV
Input quiescent current
IQ_IN
1.8
2.5
mA
380
740
435
820
490
900
mA
2580
2840
3100
400
450
500
mA
5.8
6.2
IIN(OCP)
6.0
250
3.45
155
5
V
mV
V
mV
A
τINOCBLK
200
µs
τINRECVR
150
ms
Input current limit for DCP
Input current limit for SDP
Input over-voltage protection
VIN_OVP hysteresis
Input under-voltage lockout
VUVLO hysteresis
Input over-current threshold
Input over-current blanking
(5)
time
Input over-current recover
(5)
time
IIN_LIMIT
IUSB
VIN_OVP
VIN_UVLO
Charge mode, ISYS = 0,
battery float
RlLIM = 88.7k
RlLIM = 49.9k
RlLIM = 14.7k
SDP is detected using DP1/DM1
detection
VIN rising
VIN falling
VIN rising
VIN falling
Connect VB to GND
Terminal battery voltage
Recharge threshold
Trickle charge voltage
threshold
MP2690 Rev.1.0
6/24/2016
VBATT_FULL Leave VB floating
Connect VB to VCC
Connect to VB to GND
VRECH
Leave VB floating
Connect VB to VCC
Connect VB to GND
VBATT_TC
Leave VB floating
Connect VB to VCC
Min
Typ
3.3
3.6
4.328
4.35
4.372
4.179
4.428
4.1
3.95
4.19
3
4.2
4.45
4.16
4.02
4.26
3.07
4.221
4.472
4.22
4.08
4.32
3.13
V
2.9
3.07
2.96
3.14
3.05
3.2
V
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V
5
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
ELECTRICAL CHARACTERISTICS (continued)
VIN = 5.0V, RS1 = 10mΩ, TA = +25°C, unless otherwise noted.
Parameter
Symbol Condition
Min
Trickle charge hysteresis
Battery over-voltage threshold
Max
220
VBOVP
Constant charge (CC) current
ICC
Trickle charge current
ITC
Termination charge current
Input voltage regulation
reference
Boost Mode
IBF
As a percentage of VBATT_FULL
RS1 = 10mΩ, RISET = 150k
RS1 = 10mΩ, RISET = 75k
RS1 = 10mΩ, RISET = 60.4k
RS1 = 10mΩ
VREG
SYS voltage range
Boost SYS over-voltage
protection threshold
SYS over-voltage protection
threshold hysteresis
ISYS = 100mA
Threshold over VSYS to turn off
VSYS(OVP)
the converter during boost mode
Boost quiescent current
IQ_BOOST
Programmable boost output
current-limit accuracy
Typ
101.5% 103.5% 105.5%
IOLIM
mV
VBATT_
FULL
900
1800
2230
90
1000
2000
2480
280
1100
2200
2740
400
90
200
300
mA
4.55
4.65
4.75
V
5
5.1
5.2
V
5.6
5.8
6
V
VSYS falling from VSYS(OVP)
ISYS = 0, boost mode, in test
mode with auto-off disabled
RS1 = 10mΩ, ROLIM = 150k
RS1 = 10mΩ, ROLIM = 71.5k
Units
330
0.9
1.97
1
2.11
mA
mA
mV
1.65
mA
1.1
2.25
A
SYS over-current blanking
(5)
time
SYS over-current recover
(5)
time
System load to turn off boost
(5)
Light-load blanking time
τSYSOCBLK
150
µs
τSYSRECVR
1.5
ms
Weak battery threshold
VBAT_UVLO
INOLOAD
Battery current in boost mode
50
85
16
120
mA
s
During boost
Before boost starts
2.5
2.9
2.6
3.05
V
V
VBATT = 4.2V, SYS float, VIN = 0V,
not in boost mode
13
16
μA
Sleep Mode
Battery leakage current
MP2690 Rev.1.0
6/24/2016
ILEAKAGE
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
ELECTRICAL CHARACTERISTICS (continued)
VIN = 5.0V, RS1 = 10mΩ, TA = +25°C, unless otherwise noted.
Parameter
Symbol
Condition
Min
Typ
Max
Units
Sinking 5mA
200
mV
Sinking 100mA
550
mV
Connected to 5V
0.2
μA
Indication and Logic
LED1, LED2, LED3, and LED4
output low voltage
TC output low voltage
LED1, LED2, LED3, LED4, TC
leakage current
INOVP, BOVP and NTC, fault
(5)
blinking frequency
PB input logic low voltage
PB input logic high voltage
Protection
1
0.4
1.4
CTMR = 0.1µF, remains in
TC mode, ITC = 250mA
CTMR = 0.1µF, ICHG = 1A
Trickle charge time
Total charge time
NTC low temp, rising threshold
65.2%
RNTC = NCP18XH103 (0ºC)
NTC low temp, rising threshold
hysteresis
NTC high temp, rising threshold
NTC high temp, rising threshold
hysteresis
Charging current foldback
(5)
threshold
(5)
Thermal shutdown threshold
Input DP1/DM1 USB Detection
DP1 voltage source
Data connect detect current source
DM1 sink current
Leakage current input DP1/DM1
Data detect voltage
Logic low (logic threshold)
DM pull-down resistor
Logic I/O Characteristics
RNTC = CP18XH103 (50ºC)
16
Min
390
66.2%
Min
67.2%
35.7%
36.7%
VDP_SRC
IDP_SRC
IDM_SINK
IDP_LKG
0.5
7
50
-1
IDM_LKG
VDAT_REF
VLGC_LOW
-1
0.25
120
°C
150
°C
0.6
100
0.7
13
150
1
V
μA
μA
μA
1
0.4
0.8
μA
V
V
KΩ
0.4
V
19
High-logic voltage threshold
VH
VSYS
2%
Charge mode
VL
V
V
2.4%
34.7%
Low-logic voltage threshold
MP2690 Rev.1.0
6/24/2016
Hz
1.3
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V
7
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
ELECTRICAL CHARACTERISTICS (continued)
VIN = 5.0V, RS1 = 10mΩ, TA = +25°C, unless otherwise noted.
Parameter
Symbol
Condition
Min
Typ
Max
Units
158
200
Ω
11
11
15
15
19
19
kΩ
kΩ
VOUT = 5V
VOUT = 5V
2.6
2.6
26
2.7
2.7
31
2.8
2.8
36
V
V
kΩ
DP2/DM2 output voltage
VOUT = 5V
DP2/DM2 output impedance
Voltage-Based Fuel Gauge (VOREG = 4.2V, Charge Mode)
1.21
60
1.26
78
1.31
90
V
kΩ
3.52
3.6
3.69
V
Output DP2/DM2 USB Signaling
BC1.2 DCP Mode
DP2 and DM2 short resistance
BC1.2 SDP Mode
VDP = 0.8V, IDM = 1mA
DP2 pull-down resistance
DM2 pull-down resistance
Divider Mode
DP2 output voltage
DM2 output voltage
DP2/DM2 output impedance
1.2V/1.2V Mode
First level of battery voltage
threshold
Hysteresis
Second level of battery voltage
threshold
Hysteresis
Third level of battery voltage
threshold
Hysteresis
Voltage-Based Fuel Gauge (VOREG = 4.2V, Discharge Mode)
First level of battery voltage
threshold
Hysteresis
Second level of battery voltage
threshold
Hysteresis
Third level of battery voltage
threshold
Hysteresis
Fourth level of battery voltage
threshold
Hysteresis
500
3.7
3.8
mV
3.91
500
3.92
4.0
mV
4.11
500
3.4
3.47
3.62
3.54
3.77
3.69
3.92
500
V
mV
3.84
500
3.85
V
mV
500
3.7
V
mV
500
3.55
V
V
mV
3.99
V
mV
NOTE:
5) Guaranteed by design.
MP2690 Rev.1.0
6/24/2016
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 5V, CIN = CBATT = CSYS = C2 = 22µF, L1 = 2.2µH, RS1 = 10mΩ, C4 = CTMR = 0.1µF, battery
simulator, unless otherwise noted.
MP2690 Rev.1.0
6/24/2016
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 5V, CIN = CBATT = CSYS = C2 = 22µF, L1 = 2.2µH, RS1 = 10mΩ, C4 = CTMR = 0.1µF, battery
simulator, unless otherwise noted.
MP2690 Rev.1.0
6/24/2016
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 5V, CIN = CBATT = CSYS = C2 = 22µF, L1 = 2.2µH, RS1 = 10mΩ, C4 = CTMR = 0.1µF, battery
simulator, unless otherwise noted.
MP2690 Rev.1.0
6/24/2016
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 5V, CIN = CBATT = CSYS = C2 = 22µF, L1 = 2.2µH, RS1 = 10mΩ, C4 = CTMR = 0.1µF, Battery
Simulator, unless otherwise noted.
MP2690 Rev.1.0
6/24/2016
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12
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 5V, CIN = CBATT = CSYS = C2 = 22µF, L1 = 2.2µH, RS1 = 10mΩ, C4 = CTMR = 0.1µF, battery
simulator, unless otherwise noted.
MP2690 Rev.1.0
6/24/2016
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13
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 5V, CIN = CBATT = CSYS = C2 = 22µF, L1 = 2.2µH, RS1 = 10mΩ, C4 = CTMR = 0.1µF, battery
simulator, unless otherwise noted.
MP2690 Rev.1.0
6/24/2016
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14
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
PIN FUNCTIONS
P/N
Name
I/O
Description
1
PGND
Power
Power ground.
2
SW
Power
Switch output node. It is not recommended to place vias on the SW plane during
PCB layout.
3,4
SYS
Power
System output. Place a ceramic capacitor of at least 22µF as close to SYS and
PGND as possible. The total capacitance should not be lower than 44µF.
5
VIN
Power
Adapter input. Place a bypass capacitor close to VIN to prevent large input voltage
spikes.
6
DM1
I
Negative line of the input USB data line pair. DM1 together with DP1 achieves
the USB host. DM1 has automatic charging port detection.
7
DP1
I
Positive line of the input USB data line pair. DP1 together with DM1 achieves
the USB host. DP1 has automatic charging port detection.
8
TC
O
9
ILIM
I
10
DM2
O
11
DP2
O
Torch control output. TC is the open-drain structure. The internal driver MOSFET
is on when PB is pulled low for more than 1.5ms twice within one second.
Input current setting. Connect ILIM to GND with an external resistor to program
an input current limit in charge mode when a dedicated charger is detected.
Negative line of the output USB data line pair. DM2 together with DP2
automatically provides the correct voltage signal for attached portable equipment to
perform DCP detection.
Positive line of the output USB data line pair. DP2 together with DM2
automatically provides the correct voltage signal for attached portable equipment to
perform DCP detection.
Push button input. Connect a push button from PB to AGND. PB is pulled up by a
resistor internally. When PB is set from high to low for more than 1.5ms, the boost
is enabled and latched if VIN is not available.
LED1-4 are on for five seconds whenever PB is set from high to low for more than
1.5ms.
12
PB
I
If PB is set from high to low for more than 1.5ms twice within one second and the
torch light is off, the torch light drive MOSFET is on and latched. However, if PB is
set from high to low for more than 1.5ms twice within one second and the torch
drive MOSFET is on, the torch light drive MOSFET is off.
If PB is set from high to low for more than 2.5 seconds, this is defined as a long
push, and boost is shut down manually.
Oscillator period timer. Connect a timing capacitor between TMR and GND to set
the oscillator period. Short TMR to GND to disable the timer function.
13
TMR
I
14
ISET
I
Programmable charge current. Connect an external resistor to GND to program
the charge current.
15
OLIM
I
Programmable output current limit for boost mode. Connect an external resistor
to GND to program the system current in boost mode.
MP2690 Rev.1.0
6/24/2016
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
PIN FUNCTIONS (continued)
P/N
Name
I/O
16
VCC
I
17
AGND
I/O
18
VNTC
O
Pull-up voltage source for the NTC function. VNTC is connected to VCC through
an internal MOSFET. VNTC is disconnected from VCC during sleep mode. VNTC
should be the pull-up voltage of the external NTC resistive divider.
19
NTC
I
Negative temperature coefficient (NTC) thermistor.
20
VB
I
Programmable battery full voltage. Leave VB floating for 4.2V. Connect VB to
logic high for 4.45V. Connect VB to GND for 4.35V.
21
BATT
I
Positive battery terminal/battery charge current sense negative input.
22
CSP
I
Battery charge current sense positive input.
23
LED4
O
LED4 together with LED1, LED2, and LED3 achieves the voltage-based fuel
gauge indication.
24
LED3
O
LED3 together with LED1, LED2, and LED4 achieves the voltage-based fuel
gauge indication.
25
LED2
O
LED2 together with LED1, LED3, and LED4 achieves the voltage-based fuel
gauge indication.
26
LED1
O
LED1 together with LED2, LED3, and LED4 achieves the voltage-based fuel
gauge indication.
MP2690 Rev.1.0
6/24/2016
Description
Internal circuit power supply. Bypass VCC to GND with a ceramic capacitor no
higher than 100nF.
Analog ground.
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16
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
BLOCK DIAGRAM
SYS
DM2
DP2
Output
Signaling
SW
VIN
DM1
Q1
Q3
VCC
A1
DP/DM
Detection
DP1
Q2
IIN_FB
VCC
LSMOS
Driver
LSMOS
Driver
Charge
Pump
ILIM
PWM
Controller
VNTC
A2
Input Current
Limit Setting
Q4
IIN_LMT
CSP
Sleep Mode
VC
C
VCC
Buffer
VIN
GMV
VBATT_FB
VBATT
ICC
VSYS
VIN
Current Sense
VBATT_FULL
Control Logic
&
Mode Selection
UV
OV
K1*ICHG
GMI
VBATT_FB
IIN_LMT
IIN_FB
AGND
VIN_LMT
TJ
Boost Enable
PB
GMINV
LED3
Junction
Temp Sense
Torch Control
VB
ISET
Charge
Parameter
Setting
LED2
GMT
Thermal
Protection
H/L/Floating
LED1
TRef
VBATT+
300mV
VBATT_FULL
PGND
GMINI
VIN_FB
VSYS
BATT
K1*ICHG
LED4
FG
Indication
VCC
VNTC
ICC
Battery Temp
Protection
OLIM
Boost Output
Current Limit
Setting
Timer Fault
VBATT
VTNC
TIMER
Function
TMR
NTC
Figure 1: Functional Block Diagram in Charge Mode
MP2690 Rev.1.0
6/24/2016
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17
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
BLOCK DIAGRAM (continued)
SYS
DM2
DP2
Output
Signaling
IOUT_FB
SW
VIN
DM1
Q1
Q2
Q3
DP/DM
Detection
DP1
VCC
A1
VCC
LSMOS
Driver
LSMOS
Driver
Charge
Pump
ILIM
PWM
Controller
VNTC
A2
Input Current
Limit Setting
Q4
IIN_LMT
CSP
Sleep Mode
VC
C
VCC
VSYS_REG
VBATT
IOLIM
VSYS
VIN
Current Sense
VSYS_FB
VIN
Buffer
Control Logic
&
Mode Selection
UV
OV
IOUT_FB
GMV
GMI
VBATT_FB
LED1
TRef
VBATT+
300mV
TJ
Boost Enable
LED3
Thermal
Protection
VB
ISET
Charge
Parameter
Setting
LED2
GMT
Junction
Temp Sense
Torch Control
H/L/Floating
PGND
AGND
VSYS
PB
BATT
K1*ICHG
VBATT_FULL
LED4
FG
Indication
VCC
VNTC
ICC
Battery Temp
Protection
OLIM
Boost Output
Current Limit
Setting
Timer Fault
VBATT
VTNC
TIMER
Function
TMR
NTC
Figure 2: Functional Block Diagram in Boost Mode
MP2690 Rev.1.0
6/24/2016
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18
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
OPERATION FLOW CHART
POR
No
V CC > VCC_ UVLO ?
Yes
4.65 V < VIN < 5.8 V ?
No
Yes
VIN > 5.8 V ?
SYS is Powered by VIN
No
No
No
Short Low Pulse at PB ?
USB Detection
Done ?
Input OVP
Fault
Yes
Yes
Yes
No
VBATT>2.9V ?
Input Current
Limit is Configured
Yes
Yes
Boost Mode
Any Charge Fault ?
No
No
No Load is
Detected?
Yes
No
Charge Mode
No Load Timer
Expires?
Yes
Sleep Mode
Figure 3: Mode Selection Flow Chart
MP2690 Rev.1.0
6/24/2016
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19
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
OPERATION FLOW CHART (continued)
Normal Operation
Charge Mode
Charge Mode?
VBATT = VBATT_FULL
VBATT_TC < VBATT < VBATT_FULL
VBATT < VBATT_TC
C.V.C
C.C.C
T.C.C
No
No
No
ICHG VBATT_TC ?
Yes
Yes
Yes
Charger “Off”
Yes
No
VBATT < VRECH ?
No
No
No
o
Timer Out ?
NTC Fault?
TJ ≥120 C?
Yes
Yes
Yes
Charge
Termination
Charge Suspend
Decrease ICHG to
Maintain TJ at 120oC
No
No
No
Reset
Timer?
NTC OK?
TJ ≥150oC?
Yes
Yes
Yes
Charge Recovery,
Return to Normal
Operation
Thermal Shutdown
No
Fault Protection
Yes
TJ ≤120oC?
Figure 4: Normal Operation and Fault Protection in Charge Mode
MP2690 Rev.1.0
6/24/2016
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20
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
OPERATION FLOW CHART (continued)
Power Path Management
SYS Output
Current Increase
No
VIN touch the VIN_R?
No
Yes
IIN > IIN_LIMIT?
Yes
Reduce the ICHG
ICHG ≤0?
No
Yes
IIN > 7A?
No
YES
Normal Operation
IIN > IIN_OCP?
No
Yes
Regulate IIN at IIN_OCP
Fast Turn Off the
IN-to-SYS MOSFET
NO
TINOCBLK , 200μs
reaches?
YES
After One-Shot Delay
Turn Off IN-to-SYS
MOSFET
No
150ms Timer
Expires?
Yes
Softly Turn On the
IN-to-SYS MOSFET
Figure 5: Power-Path Management in Charge Mode
MP2690 Rev.1.0
6/24/2016
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21
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
OPERATION FLOW CHART (continued)
BATT POR
Normal Boost
Operation
No
VBATT >2.9V?
VSYS3.5A?
Yes
No
Boost Enabled?
Yes
VSYS VBATT+ 300mV
Auto-recharge threshold
VBATT
0V
2V
VSYS
Band Gap
VINOK
CHG EN
REF SS
200μs
ICC
ICHG
IBF
1ms
Charge Full
Figure 7: Input Power Start-Up Time Flow in Charge Mode
MP2690 Rev.1.0
6/24/2016
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23
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
START-UP TIME FLOW IN BOOST MODE
Condition: VIN = 0V, VBATT = 3.8V
VSYS
VSYS > VCC + 150 mV
VCC
V BATT
0V
1.5ms
Band Gap
Boost EN
1.2ms
REF SS
IBATT
75mA
75mA
16s
No Load Off
Control
Figure 8: Boost Start-Up Time Flow in Boost Mode
MP2690 Rev.1.0
6/24/2016
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24
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
OPERATION
The MP2690 is a highly integrated, flexible,
switch-mode battery charger with system powerpath management designed for single-cell Li-ion
or Li-polymer battery use in a wide range of
applications. Depending on the status of the
input, the IC can operate in three different
modes: charge mode, boost mode, and sleep
mode.
In charge mode, the IC can work with a single-cell Liion or Li-polymer battery. In boost mode, the IC boosts
the battery voltage to VSYS to power higher voltage
system rails. In sleep mode, both charging and boost
operations are disabled, and the device enters a
power-saving mode to help reduce overall power
consumption. The IC monitors VIN to allow smooth
transitions between different modes of operation.
VCC Power Supply
The MP2690 has an external VCC power supply. VCC
is powered by the highest voltage level out of VSYS,
VBATT, and VIN - 0.7V. An external capacitor is required
to bypass VCC to GND. When VCC is higher than
2.2V, the internal control circuit is activated.
Charge Mode Operation
Charge Cycle
(Trickle Charge CC Charge CV
Charge)
In charge mode, the IC uses five control loops to
regulate the input current, input voltage, charge
current, charge voltage, and device junction
temperature. The IC charges the battery in three
phases: trickle current (TC), constant current
(CC), and constant voltage (CV).
When charge operation is enabled, all five loops
are active, but only one dictates the IC behavior.
A typical battery charge profile is shown in Figure
9a. The charger stays in TC charge mode until
the battery voltage reaches a TC-to-CC threshold.
Otherwise, the charger enters CC charge mode.
When the battery voltage rises to the CV mode
threshold, the charger operates in constant
voltage mode. Figure 9b shows a typical charge
profile when the input current limit loop
dominates during the CC charge mode. In this
case, the charger maximizes the charging current
due to the switching-mode charging solution,
resulting in charging that is faster than a
traditional linear charging solution.
MP2690 Rev.1.0
6/24/2016
Figure 9: Typical Battery Charge Profile
Auto-Recharge
Once the battery charge cycle is completed, the
charger remains off. During this time, the system
load may consume battery power, or the battery
may self-discharge. To ensure that the battery
does not go into depletion, a new charge cycle
begins automatically when the battery voltage
falls below the auto-recharge threshold and the
input power is present. The timer resets when the
auto-recharge cycle begins.
If the input power restarts during the off-state
after the battery is fully charged, the charge cycle
starts, and the timer resets regardless of what
the battery voltage is.
Charge Current Setting
The external sense resistors (RS1 and RISET)
program the battery charge current (ICHG). Select
RISET based on RS1.
To optimize the transfer efficiency, RS1 is
recommended to be 10mΩ. The relationship
between RISET and ICHG is shown in Equation (1):
ICHG (A)
1500
RISET (k) RS1(m)
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(1)
25
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
Battery Over-Voltage Protection (OVP)
VNTC Power Supply
The IC has battery over-voltage protection
(OVP). If the battery voltage exceeds the battery
over-voltage threshold (103.5% of the battery’s
full voltage), charging is disabled. Under this
condition, an internal 5kΩ dummy load draws a
small current from BATT to reduce the battery
voltage and protect the battery.
The MP2690 has NTC protection in both boost
mode and charge mode. To allow NTC protection
in both boost mode and charge mode and to
minimize the battery leakage current in sleep
mode, the MP2690 uses a dedicated power
supply pin for the pull-up voltage for the NTC
protection function block. In boost mode and
charge mode, VNTC is connected to VCC
internally by a switch. In sleep mode, VNTC is
disconnected from VCC to minimize the battery
leakage current (see Figure 10).
Timer Operation in Charge Mode
The IC uses an internal timer to terminate the
charging. The timer remains active during the
charging process. An external capacitor between
TMR and GND programs the charge cycle
duration.
If charging remains in TC mode beyond the
trickle-charge time (τTRICKLE_TMR), charging is
terminated. For the MP2690, the charge current
in TC mode is fixed at 265mA, and the sense
resistor (RS1) is set to 10mΩ. The length of the
trickle-charge period can be determined with
Equation (2):
VCC
VNTC
Sleep mode
Charge
Control
NTC
CTMR (F)
(2)
0.1F
The maximum total charge time can be
calculated with Equation (3):
TRICKLE _ TMR 17mins
TOTAL _ TMR 7.55Hours
CTMR (F)
1A
(3)
0.1F
ICHG (A) 0.1
Negative
Temperature
Coefficient
(NTC) Input for Battery Temperature
Monitoring
The IC has a built-in NTC resistance window
comparator, which allows the IC to monitor the
battery temperature via the battery-integrated
thermistor during both charge and boost modes.
Connect an appropriate resistor from VNTC to
NTC and connect the thermistor from NTC to
GND. The resistor divider determines the NTC
voltage depending on the battery temperature. If
the NTC voltage falls outside of the NTC window,
the IC stops charging. The operation then
restarts if the temperature goes back into the
NTC window range. Please refer to the
Application Information section on page 33 for
the appropriate resistor selection.
MP2690 Rev.1.0
6/24/2016
Figure 10: NTC Protection Block
Input DP1/DM1 USB Detection and Input
Current Limit
Power devices (PDs) are able to draw current
from the USB ports in personal computers to
charge their batteries. If the portable device is
attached to a USB host of the hub, then the USB
specification requires the portable device to draw
a limited current (usually 500mA). When the
device is attached to a charging port, it is allowed
to draw more than 1.5A.
The IC features input source detection to
determine the input current limit according to the
input source (USB or adapter) (see Figure 11).
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26
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
DP
VDP_SRC
VLGC_HI
IDP_SRC
CHG_DET
VDAT_REF
To be compatible with different capacities of the
input source, the input current limit is
recommended to be set using Table 2 if a 5V
input is requested.
IDM_SINK
DM
RDM_DWN
Figure 11: USB Port Detection
When the input source plugs in, the IC starts
DP1/DM1 detection. DP1/DM1 detection has two
steps: data contact detection (DCD) and primary
detection. DCD uses a current source to detect
when the data pins have made contact during an
attach event. The protocol for data contact
detection is as follows:
The power device (PD) detects if VBUS is
asserted.
The PD turns on DP, IDP_SRC, and the DM
pull-down resistor for 40ms.
The PD waits for the DP line to be low.
The PD turns off IDP_SRC and the DM pulldown resistor when the DP line is
detected to be low, or when the 40ms
timer expires.
DCD allows the PD to start primary detection
once the data pins have made contact. Once the
data contact is detected, the IC jumps to the
primary detection immediately. If the data contact
is not detected, the IC jumps to the primary
detection automatically after 300ms from the
beginning of the DCD.
Primary detection is used to distinguish between
the USB host (or SDP) and different types of
charging ports.
MP2690 Rev.1.0
6/24/2016
During primary detection, the PD turns on VDP_SRC
on DP1 and IDM_SINK on DM1. If the portable
device is attached to a USB host, DM1 is low. If
the power device is attached to CDP, DCP, or
another dedicated charging port, DM1 remains
high.
Table 2: Input Current Limit Setting
DP1/DM1 Detection
Floating
SDP
IIN_LMT
500mA
500mA
CDP or DCP
Set through RILIM
The USB detection runs once VIN is detected and
is independent of the charge enable status. After
the DP1/DM1 detection is done, the IC sets the
input current limit as shown in Table 2.
When the detection algorithm is completed, the
DP1 and DM1 signal lines enter a high-Z state
with approximately 4pF of capacitive load.
External Input Current Limit Setting
The IC has a dedicated pin used to program the
input current limit when CDP or DCP is detected.
The current at ILIM is a fraction of the input
current. The ILIM voltage indicates the average
input current of the switching regulator as
determined by the resistor value between ILIM
and GND. As the input current approaches the
programmed input current limit, the charge
current is reduced to give priority to the system
power.
The input current limit threshold
determined with Equation (4):
IILIM
40(k)
(A)
RILIM (k)
can
be
(4)
Input Voltage Regulation in Charge Mode
In charge mode, if the input power source is not
sufficient for supporting both the charge current
and the system load current, the input voltage
decreases. As the input voltage internally
approaches the 4.65V input voltage regulation
threshold preset, the charge current is reduced to
give priority to the system power and maintain
proper regulation of the input voltage.
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27
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
Integrated Over-Current Protection and OverVoltage Protection for Pass-Through Path
The IC has an integrated IN-to-SYS pass-through
path to allow direct connection of the input
voltage to the system. Therefore, the IC monitors
both the input current and voltage continuously.
In the event of an overload, the charge current is
reduced to ensure priority of the system power
requirements.
The IC also features input over-current and overvoltage protection for the IN-to-SYS pass-through
path.
Input Over-Current Protection (OCP)
When the total input current exceeds 5A, Q2 is
controlled linearly to regulate the current (see
Figure 12). If the current continues to exceed 5A
after 200μs of blanking time, Q2 is turned off. In
the event of the input current exceeding 7A, Q2
is turned off almost instantaneously and without
any blanking time. This is done to protect both
Q1 and Q2.
Input Over-Voltage Protection (OVP)
The IC has a built-in over-voltage threshold
(VIN_OVP). When the input voltage is higher than
VIN_OVP, an invalid input power source is detected
by the IC. At this time, the IN-to-SYS passthrough path is turned off to prevent connecting
to the wrong adapter.
SYS
Q1
Q2
IN
Charge
Pump
Figure 12: Integrated Pass-Through Path
Battery Short Protection
In charge mode, the MP2690 uses two inherent
current-limit thresholds due to a peak-currentcontrol strategy. CC and CV modes have a peakcurrent-limit threshold of 7A, while TC mode has
a current-limit threshold of 4A. Therefore, the
current-limit threshold decreases to 4A when the
battery voltage drops below the TC threshold.
The switching frequency also decreases when
MP2690 Rev.1.0
6/24/2016
the BATT voltage drops to 40% of the charge-full
voltage.
Thermal Foldback Function
The IC implements thermal protection to prevent
thermal damage to the IC and the surrounding
components. An internal thermal sense and
feedback loop decreases the programmed
charge current automatically when the die
temperature reaches 120°C. This function is
called the charge-current-thermal foldback. This
function protects against thermal damage and
sets the charge current based on requirements
rather than worst-case conditions while ensuring
safe operation. The part also includes thermal
shutdown protection, where the charging process
is stopped if the junction temperature rises to
150°C.
Non-Sync Operation Mode
During charging mode, the IC monitors the total
input current flowing from IN to SYS continuously.
When the input current is lower than 170mA, the
low-side switch operates as a non-synchronous
MOSFET.
Constant Off-Time Control for Large
Duty Charging Operation
The IC has a built-in 600kHz frequency oscillator
for the switching frequency. Unlike a traditional
fixed-frequency, peak-current control, the IC
features a constant-off time control to support a
constant current charge even when the input
voltage is very close to the battery voltage. The
IC compares the high-side MOSFET sense
current with the comp level continuously (see
Figure 13). If the sense current does not reach
the comp level within the original switching period,
the next clock is delayed until the sense current
reaches the comp level. As a result, the duty
cycle is able to be extended as long as possible.
Indication for Fault Flag in Charge
Mode
The MP2690 is designed with distinct indication
separating the charging fault from the normal
operation. At the charging fault, including INOVP,
BOVP, and NTC fault, the four LED pins blink
with a 1Hz frequency simultaneously (see Table
3).
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28
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
Table 3: Indication at Charge Mode
Operation Status
Normal charging
Charge full
VIN UVLO
VIN OVP, NTC fault,
battery OVP
LED1 to LED4 State
Depending on the battery voltage,
LEDx blinks at 1Hz (refer to Fuel
Gauge Indication section)
LED1 to LED4 are all turned on
LED1 to LED4 are all turned off
LED1 to LED4 are all blinking at 1Hz
Comp
Slope Compensation
HS Sense Current
Constant Off Time
HS Signal
600kHz
Lower the Fsw to support larger Duty
Figure 13: Constant-Off Time Operation Profile
Boost Mode Operation
Low-Voltage Start-Up
The minimum battery voltage required to start up
the circuit in boost mode is 2.9V. Initially, when
VSYS is less than VBATT, the IC works in down
mode. In this mode, the synchronous P-FET
stops switching and its gate connects to VBATT
statically. The P-FET stays off for as long as the
voltage across the parasitic CDS (VSW) is lower
than VBATT. When the voltage across CDS
exceeds VBATT, the synchronous P-FET enters
linear mode, allowing the inductor current to
decrease and flow into SYS. Once VSYS exceeds
VBATT, the P-FET gate is released and the normal
closed-loop PWM operation is initiated. In boost
mode, the battery voltage can drop as low as
2.5V without affecting circuit operation.
Board layout is extremely critical for minimizing
voltage overshoot at SW due to stray inductance.
Keep the output filter capacitor as close to SYS
as possible and use very low ESR/ESL ceramic
capacitors tied to a good ground plane.
Boost Output Voltage Setting
In boost mode, the IC programs the output
voltage internally according to the load
connected to SYS (5.1V or 5.2V) and provides
built-in output over-voltage protection (OVP) to
protect the device and other components against
damage when VSYS goes beyond 6V. Once
output over-voltage occurs, the IC turns off the
boost converter. When the voltage on VSYS drops
to a normal level, the boost converter restarts
again when PB is set from high to low for more
than 1.5ms.
SYS Disconnect and Inrush Limiting
Boost Output Current Limiting
The IC can achieve true output disconnect by
eliminating body diode conduction of the internal
P-FET rectifier. VSYS can go to 0V during
shutdown, drawing no current from the input
source. It also allows for inrush current limiting at
start-up, minimizing surge currents from the input
supply. To optimize the benefits of the output
disconnect, avoid connecting an external
Schottky diode between SW and SYS.
The IC integrates a programmable output current
limit function in boost mode. If the boost output
current exceeds this programmable limit, the
output current is limited at this level and the SYS
voltage begins to drop down. OLIM programs the
current limit threshold up to 2.1A, per Equation
(5):
1500
IOLIM (A)
(5)
ROLIM (k) RS1(m)
MP2690 Rev.1.0
6/24/2016
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29
MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
The MP2690 can operate in CC mode when the
current limit is reached, and VIN does not drop to
the down mode threshold (VBATT + 100mV) (see
Figure 14).
VSYS
VSYS_REG
Thermal Shutdown Protection
The thermal shutdown protection is also active in
boost mode. Once the junction temperature rises
higher than 150°C, the IC enters thermal
shutdown and does not resume normal operation
until the junction temperature drops below 120°C.
Automatic Off at Light Load
The boost turns off automatically if the load
current at BATT is below the typical 75mA value
for 16 seconds.
VBATT+100mV
SCP
IOLIM
ISYS
Figure 14: Boost Output U-I Curve
The MP2690 not only has CC mode during the
charging process, but also has CC mode
operation in boost mode for various applications.
SYS to BATT Block Protection
When there is no VIN and the boost mode is not
on, the part is in sleep mode. The HS switch
implements the body switch function, which
connects the body diode of the switch to the
high-voltage side of SW and SYS, which blocks
the external voltage on SYS from flooding into
the battery.
SYS Output Over-Current Protection (OCP)
The IC integrates a three-phase output overcurrent protection.
The MP2690 also features a long-push action on
PB to shut down the boost manually. A low push
on PB longer than 2.5 seconds is defined as a
long push (see Figure 14 for PB action).
Automatic Output DP2/DM2 Signaling
In boost mode, the IC sets the DP2/DM2 signal
based on the load applied on USB2. In passthrough mode, DP2 and DM2 are set according
to DP1/DM1 detection results.
In boost mode, DM2/DP2 are set based on three
types of signals: DM2/DP2 separately biased
with a 2.7V voltage signal (default), DM2/DP2
shorted, and DM2/DP2 shorted with a 1.2V bias.
In pass-through mode, DM2/DP2 are connected
together if the dedicated charger ports are
detected, and pulled down to ground separately
with a 15kΩ resistor if SDP is identified.
Torch Control
1. Phase one (boost mode output current limit):
When the output current exceeds the
programmed output current limit, the output
constant current loop controls the output
current, the output current remains at its limit
(IOLIM), and VSYS decreases.
If the internal torch drive FET is off when PB is
pulled from high to low for more than 1.5ms twice
within one second, the drive FET is turned on.
Conversely, if the torch drive FET is on, the drive
FET is turned off.
2. Phase two (down mode): When VSYS drops
below VBATT + 100mV, and the output current
loop remains in control, the boost converter
enters down mode and shuts down after
120μs of blanking time.
PB Control
3. Phase three (short-circuit mode): When VSYS
drops below 4.0V (2V during boost soft start),
the boost converter shuts down immediately
once the inductor current hits the foldback
peak-current limit of the low-side N-FET. The
boost
converter
can
also
recover
automatically after a 1ms deglitch period.
MP2690 Rev.1.0
6/24/2016
Once the torch light is turned on, the automaticoff function is blocked.
PB is used to control the enable of boost mode.
Pull PB from high to low for more than 1.5ms to
enable boost mode; pull PB from high to low for
2.5s to disable boost mode.
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
Automatic On when Load is Applied
The boost turns on automatically when PB is
pulled from high to low for more than 1.5ms, or
when the load is plugged in to USB2 using the
PB control.
To detect the USB load plug-in, the RC network
is connected to the USB port shield floating in the
PCB. Once the USB load is inserted, the USB
connector shield is grounded through the USB
load. So a short pulse (high to low for more than
1.5ms) is generated in PB, resulting in the start of
boost.
An RC network can also be connected in VBUS of
the USB output port. During load insertion, the
load input cap generates a high-to-low pulse for
more than 1.5ms to start the boost (see Figure
15). The circuit in the dash frame is the automatic
load detection circuit. M2 is used to decouple the
USB port from the VSYS cap (C2, CSYS), and M1 is
used to drive M2.
4-LED Driver for Voltage-Based Fuel
Gauge
The IC provides 4-LED drivers for a voltagebased fuel gauge. The driver is connected to an
internal open-drain FET. The 4-LED indication
values are shown in Table 4.
The LED threshold can be programmed using a
fuse. Each threshold can be adjusted from
150mV to 200mV with 50mV steps from their
default value.
The LED threshold is also adjusted automatically
based on the VBAT_REG setting. The VOREG
difference is considered to be offset for LED
thresholds.
During voltage measurement, the battery
impedance (50mΩ) should be compensated
based on the battery current to get a precise
battery voltage for fuel gauge indication.
Indication for Fault Flag in Boost Mode
Once a phone is plugged in, the voltage at CUSB is
pulled down because the input cap inside the
phone is far larger than CUSB, so the falling edge
is delivered to PB to enable boost automatically.
To minimize the power consumption of the
battery, the indication is active once PB is shortpushed in normal discharge operation, and turns
off after five seconds automatically.
M3 is used to cut off PB to and from the USB port
when boost is turned on. The PB state is not
affected by the spec of the inserted load of the
USB port. Choose M3 with a low turn-on
threshold (-0.7V is recommended) which can
ensure that it is fully on when the load is inserted
and that its on resistance does not cause too
much of a voltage drop.
Table 4: Indication at Discharge Mode
Operation status
LED1 to LED4 state
Normal discharging
Depending on the battery
voltage, LEDx is turned off.
(refer to Fuel Gauge
Indication section)
NTC fault
LED1 to LED4 are all blinking
at 1Hz
1.5ms
1.5ms
PB
2.5s
2.5s
TMR
2.5s
2.5s
2.5s
2.5s
Boost EN
Off
Off
On
t0
(1st Push)
t1
(2nd Push)
t2
(3rd Push)
On
t3
(4th Push)
Figure 15: PB Action Profile
MP2690 Rev.1.0
6/24/2016
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MP2690 – ALL-IN-ONE, 2.5A SW CHARGER, 2.1A BOOST
Table 5: Indication during Normal Operation
Mode
VBATT
VBATT < 3.6V
[3.6V, 3.8V)
[3.8V, 4.0V)
CV mode, [4.0V, 4.2V),
not terminated
Charging
VBATT ≥ 4.0, terminated
Discharging
(All off after 5s)
MP2690 Rev.1.0
6/24/2016
VBATT ≥ 3.92V
[3.77V, 3.92V)
[3.62V, 3.77V)
[3.47V, 3.62V)
[VBAT_ULVO, 3.45V)
VBATT < VBAT_UVLO
SOC
75%
[50%, 75%)
[25%, 50%)
[5%, 25%)
[1%, 5%)
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