MP2636
The Future of Analog IC Technology
3.0A Single Cell Switch Mode Battery Charger
with Power Path Management (PPM)
and 3.0A System Boost Current
DESCRIPTION
FEATURES
The MP2636 is a highly-integrated, flexible
switch-mode battery charger with system power
path management, designed for single-cell Liion or Li-Polymer batteries used in a wide range
of portable applications.
The MP2636 can operate in both charge mode
and boost mode to allow full system
management and battery power management.
When input power is present, the device
operates in charge mode. It automatically
detects the battery voltage and charges the
battery in three phases: trickle current, constant
current and constant voltage. Other features
include charge termination and auto-recharge.
This device also integrates both input current
limit and input voltage regulation in order to
manage input power and meet the priority of the
system power demand.
In the absence of an input source, the MP2636
switches to boost mode through the MODE pin
to power the SYS pins from the battery. The
OLIM pin programs the output current limit in
boost mode. The MP2636 also allows an output
short circuit protection to completely disconnect
the battery from the load in the event of a short
circuit fault. Normal operation will recover as
soon as the short circuit fault is removed. The
MP2636 provides full operating status indication
to distinguish charge mode from boost mode. In
addition, the MP2636 can report the real battery
current in both charge and boost mode via IB
pin.
The MP2636 achieves good EMI/EMC
performance with well controlled switching
edges.
Up to 16V Sustainable Input Voltage
4.5V-to-6V Operation Voltage Range
Power Management Function, Integrated
Input-Current
Limit,
Input
Voltage
Regulation
Up to 3.0A Programmable Charge Current
Trickle-Charge Function
Analog Voltage Output IB pin for Battery
Current Monitor
Selectable 4.2V / 4.3V / 4.35V Charge
Voltage with 0.5% Accuracy
Negative Temperature Coefficient Pin for
Temperature Monitoring
Programmable Timer Back-up Protection
Thermal
Regulation
and
Thermal
Shutdown
Internal Battery Reverse Leakage Blocking
Integrated Over Current Protection and
Over Voltage Protection for Pass-through
Path
Reverse Boost Operation Mode for System
Power
Up to 3.0A Programmable Output Current
Limit for Boost Mode
Integrated Short Circuit Protection and
Output Over Voltage Protection for Boost
Mode
APPLICATIONS
Sub-Battery Applications
Power-bank Applications for Smart-Phone,
Tablet and Other Portable Devices
All MPS parts are lead-free and adhere to the RoHS directive. For MPS green
status, please visit MPS website under Products, Quality Assurance page.
“MPS” and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
To guarantee safe operation, the MP2636 limits
the die temperature to a preset value of 120oC.
Other safety features include input over-voltage
protection, battery over-voltage protection,
thermal
shutdown,
battery
temperature
monitoring, and a programmable timer to
prevent prolonged charging of a dead battery.
MP2636 Rev.1.02
12/21/2018
www.MonolithicPower.com
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© 2018 MPS. All Rights Reserved.
1
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
TYPICAL APPLICATION
To 5V System
R1
R2
ROLIM
C2
SYS
IB
CSYS
OLIM
FB
5V Input
SW
L1
ICHG
IBATT
VIN
RH
CIN
Q1
R3
Q2
REG
Q3
Q4
CBATT
CSP
BATT
R4
ACOK
FREQ
BOOST
EN
VCC
ISET
MODE
ILIM
Battery Voltage
Programmable Pin
VB
CHG
VCC
RILIM
Battery
NTC
MP2636
C4
VBATT
VSYS
PWIN
RL
MP2636 Rev.1.02
12/21/2018
RS1
AGND
PGND
TMR
CTMR
RISET
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© 2018 MPS. All Rights Reserved.
2
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
Table 1: Operation Mode
Power Source
VIN
PWIN
VBATT+300mV 7A?
No
YES
Normal Operation
iIN > 125% x IIN_LMT?
No
Yes
Try to regulate iIN at
125% x IIN_LMT
Fast Turn Off the
IN-to-SYS MOSFET
No
iIN > 140% x IIN_LMT
for 120us?
Yes
Turn Off IN-to-SYS
MOSFET
No
100ms Timer
Expires?
Yes
Softly Turn On the
IN-to-SYS MOSFET
Figure 5: Power-path Management in Charge Mode
MP2636 Rev.1.02
12/21/2018
www.MonolithicPower.com
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© 2018 MPS. All Rights Reserved.
23
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
OPERATION FLOW CHART (Continued)
Normal Boost
Operation
VSYS4A?
No
VSYS IOLIM?
Yes
No
Yes
No
Output current loop
keeps ISYS=IOLMT,
VSYS decreases
Output Current Limit and Protection
Figure 6: Operation Flow Chart in Boost Mode
MP2636 Rev.1.02
12/21/2018
www.MonolithicPower.com
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© 2018 MPS. All Rights Reserved.
24
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
START UP TIME FLOW IN CHARGE MODE
Condition: EN = 5V, Mode = 0V, /ACOK and /CHG are always pulled up to an external constant 5V
VIN
VPWIN > 0.8V
&
VIN > VBATT+ 300mV
0V
5V
EN 0V
Mode
0V
VCC
VCC follows VIN
2.2V
Band
Gap 0V
5V
ACOK 0V
VSYS > VBATT + 50mV
VSYS
5V
CHG
0V
400μs
400μs
SS
150μs
150μs
Force
Charge
ICC
Charge 0A
Current
10%ICC
IBF
Comparator
Battery
Voltage
VBATT_FULL
Auto-recharge threshold
Assume vBATT > VBATT_TC
Autorecharge
Figure 7: Input Power Start-up Time Flow in Charge Mode
MP2636 Rev.1.02
12/21/2018
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.
25
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
START UP TIME FLOW IN CHARGE MODE
Condition: VIN = 5V, Mode = 0V, /ACOK and /CHG are always pulled up to an external constant 5V.
VIN
0V
5V
EN 0V
Mode 0V
VCC
2.2V
Band
Gap 0V
5V
ACOK 0V
VSYS
5V
CHG
0V
400μs
400μs
400μs
SS
150μs
150μs
150μs
Force
Charge
ICC
Charge 0A
Current
10%ICC
IBF
Comparator
VBATT_FULL
Battery
Voltage
Assume vBATT > VBATT_TC
Autorecharge
Figure 8: EN Start-up Time Flow in Charge Mode
MP2636 Rev.1.02
12/21/2018
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.
26
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
START UP TIME FLOW IN BOOST MODE
Condition: VIN = 0V, Mode = 5V, /Boost is always pulled up to an external constant 5V.
Figure 9: Battery Power Start-up Time Flow in Boost Mode
MP2636 Rev.1.02
12/21/2018
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.
27
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
START UP TIME FLOW IN BOOST MODE
Condition: VIN = 0V, /Boost is always pulled up to an external constant 5V.
VBATT
2.9V
VCC follows VSYS
VCC follows VBATT
VCC
2.2V
5V
0V
MODE
5V
Band
Gap
0V
5V
BOOST
0V
1.2ms
Boost
SS
VSYS
Down
Mode
0V
VSYS>VBATT+300mV
Figure 10: Mode Start-up Time Flow in Boost Mode
MP2636 Rev.1.02
12/21/2018
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.
28
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
OPERATION
INTRODUCTION
The MP2636 is a highly-integrated, flexible,
synchronous switch-mode battery charger with
system power path management, designed for
single-cell Li-ion or Li-polymer batteries used in a
wide range of applications. Depending on the
status of the Input supply, the MP2636 can
operate in three modes: charge mode, boost
mode and sleep mode.
In charge mode, the MP2636 can work with
single cell Li-ion or Li-polymer battery. In boost
mode, MP2636 boosts the battery voltage to
VSYS_SET to power higher voltage system rails. In
sleep mode both charging and boost operations
are disabled and the device enters a sleep mode
to help reduce the overall power consumption.
The MP2636 monitors VIN to allow smooth
transition between different modes of operation.
CHARGER MODE OPERATION
Charge Cycle
In charge mode, the MP2636 has five control
loops to regulate input voltage, input current,
charge current, charge voltage and device
junction temperature. The MP2636 charges the
battery in three phases, trickle current (TC),
constant current (CC), and constant voltage (CV).
While charge operation is enabled, all five loops
are active but only one determines the IC
behavior. A typical battery charge profile is
depicted in Figure 11(a). 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 12(b) shows a typical charge profile when
the input-current-limit loop dominates during the
CC charge mode, and in this case the charger
maximizes the charging current due to the
switching-mode charging solution, resulting in
faster charging than a traditional linear solution.
MP2636 Rev.1.02
12/21/2018
CC>>>CV
Threshold
ICHG
Constant
Charge
Current
VBAT
TC>>>CC
Threshold
Trickle
Charge
Current
Trickle charge
CC charge
CV charge
Charge Full
a) Without input current limit
CC>>>CV
Threshold
ICHG
Constant
Charge
Current
VBAT
TC>>>CC
Threshold
Trickle
Charge
Current
Trickle charge
CC charge
CV charge
Charge Full
b) With input current limit
Figure 11: Typical Battery Charge Profile
Auto-recharge
Once the battery charge cycle completes, the
charger remains off. During this time, the external
load may consume battery power, or the battery
may self discharge. To ensure the battery will not
go into depletion, a new charge cycle
automatically begins when the battery voltage
falls below the auto-recharge threshold when the
input power is present. The timer is reset when
the auto-recharge cycle begins.
During the off state after the battery is fully
charged, if the input power re-starts or the EN
signal refreshes, the charge cycle will start and
the timer will re-set no matter what the battery
voltage is.
Battery Over-Voltage Protection
The MP2636 has battery over-voltage protection.
If the battery voltage exceeds the battery overvoltage threshold, (102.5% of the battery full
voltage), charging is disabled. Under this
condition, an internal 5kΩ dummy load draws a
current from the BATT pin to decrease the
battery voltage and protect the battery.
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© 2018 MPS. All Rights Reserved.
29
MP2636 –3.0A SINGLE CELL SW MODE BATTERY CHARGER WITH PPM AND 3.0A BOOST
Timer Operation
The MP2636 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, τTC_TMR, the charging will
terminate. The following equation determines the
length of the trickle-charge period:
4.5 104 1.6(V) CTMR (F)
TC _ TMR
(s) (1)
1.25 ITC (A) RS1(m) 2(A)
The maximum total charge time is:
TOTAL _ TMR
3.4 106 1.6(V) CTMR (F)
(s) (2)
1.25 ICHG (A) RS1(m ) 2(A)
Negative Thermal Coefficient (NTC) Input
The MP2636 has a built-in NTC resistance
window comparator, which allows MP2636 to
monitor the battery temperature via the batteryintegrated thermistor. Connect an appropriate
resistor from VSYS to the NTC pin and connect the
thermistor from the NTC pin 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 MP2636
stops charging. The charger will then restart if the
temperature goes back into NTC window range.
During the NTC fault, the charge timer is
suspended.
Input Voltage Range for Different Operating
Mode
MP2636 operates in different mode based on the
state of the input. (see Table 1)
Charge Mode: A resistor divider connected to
the input and centered at PWIN pin determines
the input voltage UVLO point in charge mode of
the MP2636.
RL
(3)
VPWIN VIN
(V)
RH RL
minimum input voltage at 4.5V.
Boost Mode: Boost mode can be enabled via
the MODE pin as long as the input voltage is
higher than 6V or the voltage at PWIN is lower
than 0.8V.
Sleep Mode: when the input voltage is lower
than 2V, the MP2636 enters sleep mode
operation thus consuming very low current from
the battery.
Input Current Limiting in Charge Mode
The MP2636 has a dedicated pin that programs
the input-current limit. The average input current
of the MP2636 is determined by the resistor
value between ILIM and GND. As the total input
current approaches the programmed input
current limit, charge current is reduced to allow
priority to system power.
Use the following equation to determine the input
current limit threshold,
IILIM (A)
43.3(k)
0.05
RILIM (k)
(4)
Input Voltage Regulation in Charge Mode
In charge mode, if the input power source is not
sufficient to support the charge current and
system load current, the input voltage will
decrease. As the input voltage approaches the
programmed input voltage regulation value, the
charge current is reduced to allow priority of the
system power and maintain proper regulation of
the input voltage.
The input voltage can be regulated by resistor
divider from IN pin to REG pin to AGND
according to the following equation:
VREG VIN_ R
R4
(V)
R3 R4
(5)
where VREG is the internal voltage reference,
which is 1.2V, and the VIN_R is the desired
regulation voltage.
If the voltage at PWIN pin is higher than 0.8V,
and the input voltage is lower than 6.0V, the
MP2636 works in the charge mode. During
normal operation (VUVLO