MP26053
28V, 1A Li-Ion/Li-Polymer Battery Charger
With 10% Battery-Full Threshold,
Trickle Charge and Timer
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP26053 is a linear, high-performance
single cell Li-Ion/Li-Polymer battery charger. By
integrating high voltage input protection into the
charger IC, the MP26053 can tolerate an input
surge up to +28V. In addition, the MP26053
features an internally programmed precision
battery full-threshold of 10% of ICHG.
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The device features constant current (CC) and
constant voltage (CV) charging modes with
programmable charge currents (200mA to 1A),
current blocking, and trickle charge. The device
also provides fault and charge status
indications to the system.
Proprietary VIN Surge Protection up to 28V
10% Battery-Full Threshold
Programmable Charge Current :
200mA to 1.0A
Trickle Charge
40µA Shutdown Current
7V Input OVP
Auto Recharge
Charge-Timer
Fault and Charge Status Indicators
APPLICATIONS
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For guaranteed safe operation, the MP26053
reduces charge current when the device
reaches high temperature (due to limited PCB
space). Other safety features include battery
temperature monitoring and programmable
timer to complete the charging cycle.
Cell Phones
Digital Cameras
Smart Phones
PDAs
MP3 Players
“MPS” and “The Future of Analog IC Technology” are Registered Trademarks of
Monolithic Power Systems, Inc.
The MP26053 is available in 10-pin 3mm x
3mm QFN packages.
TYPICAL APPLICATION
VIN
3.5V - 6.5V
To system
IBATT
1
2
3
4
5
IN
BATT
ACOK
NTC
10
9
MP26053
CHG
ISET 8
TMR
SS
GND
SHDN
VBATT
7
6
CSS
ON OFF
MP26053 Rev. 0.9
8/25/2008
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© 2008 MPS. All Rights Reserved.
1
MP26053 – 28V, 1A LINEAR BATTERY CHARGER WITH TRICKLE CHARGE AND TIMER
ABSOLUTE MAXIMUM RATINGS (1)
PACKAGE REFERENCE
1
10
2
9
3
8
4
7
5
6
IN to GND .................................... –0.3V to +28V
ACOK and CHG Maximum Sink Current........20mA
All Other Pins to GND..................-0.3V to +6.5V
Junction Temperature...............................140°C
Lead Temperature ....................................260°C
Storage Temperature ..............–65°C to +150°C
Recommended Operating Conditions
Nominal Supply Voltage VIN............ 3.5V to 6.5V
Operating Temperature .............–40°C to +85°C
Thermal Resistance
Part Number*
MP26053DQ
*
Package
QFN10
(3mm x 3mm)
(2)
Temperature
–40°C to +85°C
For Tape & Reel, add suffix –Z (e.g. MP26053DQ–Z)
For RoHS compliant packaging, add suffix –LF
(e.g. MP26053DQ–LF–Z)
(3)
θJA
θJC
3x3 QFN10 ............................. 50 ...... 12... °C/W
Notes:
1) Exceeding these ratings may damage the device.
2) The device is not guaranteed to function outside of its
operating conditions.
3) Measured on approximately 1” square of 1 oz copper. The
exposed pad must be Soldered to a ground plane
ELECTRICAL CHARACTERISTICS
VIN = 5V, VSHDN = 0V, TA = +25°C, unless otherwise noted.
Parameter
Symbol Condition
Supply Current
ISUPPLY
Battery Voltage Regulation
Constant Current
Regulation
VBATT
SHDN = High
SHDN= Low, ICHG = 0A,
VBATT=4.1V
T = –5°C to +75°C, IBATT = 0
VIN = 5V, VBATT = 3.8V
RCHG = 3.3kΩ
VIN = 5V, VBATT = 3.8V,
TJ = 0°C to +120°C,
RCHG = 1.6kΩ to 8.0kΩ
Min
Typ
Max
Units
40
µA
200
µA
4.16
4.20
4.24
V
448
515
582
mA
87
100
113
%ICHG(4)
7.5
5
2.45
10
10
2.6
100
12.5
15
2.75
%ICHG(4)
%ICHG(4)
V
mV
Input ACOK Up Range
6.7
7
7.3
V
Input ACOK Low Range
1.5
2
2.5
V
ICHG
Constant Current Variation
End of Charge Threshold
Trickle Current
Trickle Threshold Voltage
Trickle Voltage Hysteresis
ACOK and CHG Overvoltage Clamp
Input Over Voltage
Protection
OVP Hysteresis
MP26053 Rev. 0.9
8/25/2008
IBF
VIN = 5V, VBATT = 2.3V
8.2
VZ
OVP
VIN Rising
6.7
7
400
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© 2008 MPS. All Rights Reserved.
V
7.3
V
mV
2
MP26053 – 28V, 1A LINEAR BATTERY CHARGER WITH TRICKLE CHARGE AND TIMER
ELECTRICAL CHARACTERISTICS (continued)
VIN = 5V, VSHDN = 0V, TA = +25°C, unless otherwise noted.
Parameter
Symbol
Condition
SHDN Trip Threshold High
Min
Typ
2.6
0.4
ISHDN
VSHDN=3V
CHG , ACOK Sink Current
Pin Voltage = 0.4V
Battery Reverse Current to
BATT Pin
SHDN = Low and Input = Floating or
0V
VIN Reverse Current
Grount current at Vin=-6V
Dropout Voltage
VIN-VBATT
Die Temperature Limit
Recharge Voltage
Threshold
6
VRECHARGE
mA
1
10
mA
0.25
V
120
135
°C
3.9
4.0
4.1
V
100
VNTC_UP
VIN=5.00V, NTC pin voltage rising
1.71
NTC Upper Trip Hysteresis
NTC Lower Threshold
1.76
mV
1.81
75
VNTC_LOW
VIN=5.00V, NTC pin voltage falling
0.35
NTC Lower Trip Hysteresis
Oscillation Freq
µA
105
Recharge Voltage
Hysteresis
NTC Upper Threshold
V
µA
8
VBATT = 3.8V, RCHG = 6kΩ. Current
drop 10%
Units
V
SHDN Trip Threshold Low
SHDN Pull up Current
Max
0.38
V
mV
0.41
V
20
mV
CTMR = 2.2uF
5
Hz
TMR Pin Source Current
ITMR1
VTMR=0.1V
20
µA
TMR Pin Sink Current
ITMR2
VTMR=1.5V
20
µA
From Trickle to 90% Full Current,
CSS=0.1µF
80
mS
Soft Start Time
Notes:
4) ICHG is the target preprogrammed charge current (Die temperature below 110°C).
MP26053 Rev. 0.9
8/25/2008
www.MonolithicPower.com
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2008 MPS. All Rights Reserved.
3
MP26053 – 28V, 1A LINEAR BATTERY CHARGER WITH TRICKLE CHARGE AND TIMER
PIN FUNCTIONS
Pin #
Name
1
VIN
2
ACOK
3
CHG
Open-Drain Charge Indicator. This pin is low during charging, is high after battery full
or termination, and is toggling when the battery is in fault condition.
TMR
Oscillator Period Timer. Connect a timing capacitor between this pin and GND
to set the oscillator period. The total charge time: T( SEC ) = 22 × 10 3 * C TMR ,
4
Description
Input Supply Pin. VIN receives the AC adapter or USB supply voltage.
Open-Drain Fault Status Indicator. This pin is high under any fault conditions.
where CTMR is in µF.
5
6
7
8
9
10
GND, Exposed
The exposed pad and GND pin must be connected to the same ground plane.
Pad
SHDN
Charger IC Enable. An input “Low” signal at this pin or pin floating will enable the IC.
SS
Soft-Start. Connect a capacitor to ground to set the soft-start time.
Constant Charge Current Program Pin. Connect this pin to an external resistor to
ISET
program the charging current in CC Mode.
Negative Temperature Coefficient (NTC) Thermistor Pin. Connect a 50kΩ resistor from
this pin to the VIN pin and a 10kΩ NTC resistor (within the battery pack) from this pin
NTC
to ground. If NTC function is not used, replace NTC resistor with a regular 10kΩ
resistor from this pin to ground. Do not leave this pin floating.
BATT
Charger Output.
BLOCK DIAGRAM
IN
CSS
SS
NTC
VIN
CIN
1
7
9
BATT I
BATT
RNTC
10
TMR
CTMR
ISET
8.2V
4
BATTERY
CHARGE
CONTROL
CHG
+
VBATT
_
COUT
3
VZ
8
RCHG
8.2V
ACOK
2
VZ
6
ON OFF
SHDN
5
GND
Figure 1—Functional Block Diagram
MP26053 Rev. 0.9
8/25/2008
www.MonolithicPower.com
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© 2008 MPS. All Rights Reserved.
4
MP26053 – 28V, 1A LINEAR BATTERY CHARGER WITH TRICKLE CHARGE AND TIMER
TYPICAL PERFORMANCE CURVES
CIN = 4.7µF, COUT = 2.2µF, CSS = 0.1µF, VIN = 5V, TA = +25°C, unless otherwise noted.
Battery Charge Curve
600
4.50
3.00
300
VSTAT
2.25
200
1.50
100
0.75
0
0
32
64
96
TIME (Min)
128
Charge Current vs
Battery Voltage
ICHG (mA)
ICHG
400
1000
VSTAT (V)
ICHG (mA)
3.75
1200
VBAT (V)
VBAT
500
I CHG=1A
800
I CHG=0.8A
600
I CHG=0.5A
400
I CHG=0.2A
200
0
0
160
0
1.0
1000
1000
ICHG (mA)
I CHG=0.8A
I CHG=0.5A
600
400
800
VBAT=4V
0
2.7
3.0
3.3
3.6
3.9
VBAT=4.1V
400
0.2
200
0.1
0
4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0
VIN (V)
Shut Down Low
Shut Down High
VIN = 5V, ISET Resistor = 2.26K
VIN = 5V, ISET Resistor = 2.26K
VBAT = 3.8V
VIN
5V/div.
VSD
2V/div.
VIN
5V/div.
VSD
2V/div.
VBAT
2V/div.
VBAT
2V/div.
MP26053 Rev. 0.9
8/25/2008
0
0
200
400
600
ISET (mA)
800
1000
Power Ramp Up vs.
Battery Charge
VIN = 5V, ISET Resistor = 2.3K
VIN
5V/div.
VCHG
2V/div.
VBAT
2V/div.
ICHG
0.5A/div.
ICHG
0.5A/div.
4ms/div.
0.4
0.3
VBAT (V)
ICHG
0.5A/div.
1/RSET vs.
ISET
600
4.2
5.0
0.5
I CHG=0.2A
200
4.0
0.6
1200
I CHG=1A
800
2.0
3.0
VBAT (V)
ICHG Current vs
Input Voltage
1200
ICHG (mA)
Charge Current vs
Battery Voltage
4ms/div.
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© 2008 MPS. All Rights Reserved.
40ms/div.
5
MP26053 – 28V, 1A LINEAR BATTERY CHARGER WITH TRICKLE CHARGE AND TIMER
TYPICAL PERFORMANCE CURVES (continued)
CIN = 4.7µF, COUT = 2.2µF, CSS = 0.1µF, VIN = 5V, TA = +25°C, unless otherwise noted.
570
40
560
30
550
20
ICHG (mA)
50
540
10
530
0
520
MP26053 Rev. 0.9
8/25/2008
www.MonolithicPower.com
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2008 MPS. All Rights Reserved.
6
MP26053 – 28V, 1A LINEAR BATTERY CHARGER WITH TRICKLE CHARGE AND TIMER
OPERATION
Input Voltage Range
The MP26053 has built-in input voltage surge
protection as high as +28V. The charger IC will
be automatically disabled when the input
voltage is lower than 3.0V or higher than 7.0V.
The open-drain pin ACOK is used to indicate
an input power good condition (i.e.
3.0V
CV)
Figure 2 shows the typical charging profile for
the MP26053. For a fully depleted battery with a
terminal voltage lower than 2.6V, the MP26053
will
start
with
the
trickle
charge
(preconditioning) at 10% of the full charge
current based on the value of RCHG. If the
charger stays in trickle mode longer than 32768
cycles, CHG becomes high impedance,
indicating a battery fault. After the battery
voltage reaches 2.6V, the charger begins
charging using the programmed charge current
(ICHG).This is referred to as Constant Current
(CC) mode. Once the battery voltage reaches
4.2V, the charger will operate in the constant
voltage (CV) mode until the battery is fully
charged. The charge current drops during CV
mode, and the battery full indication is set when
the charge current is reduced to 10% of the
programmed constant current value (ICHG). The
charge process is then terminated. Recharge
will start after the battery voltage is reduced to
4.0V. After 262144 cycles of continuous
charging, if the battery still has not reached
10% of the ICHG condition, the on-chip timer will
terminate the charger to prevent charging the
dead battery excessively and the fault condition
will be flagged by flashing the CHG LED.
Charge Termination
The charge current will gradually decrease in
CV mode as the battery approaches full. The
MP26053 Rev. 0.9
8/25/2008
battery full threshold is internally programmed
to be 10% of the ICHG. When the charge current
reaches this threshold, the charger IC will be
automatically turned off.
IBATT
CC
Charging
ICHG
CV
Charging
10% of ICHG
Charging
Complete
Trickle
Charging
VBATT
2.6V
4.2V
Figure 2—MP26053 Typical Charging Profile
Automatic Recharge
When VBATT drops to 4.0V, the charger will
automatically restart the charge cycle until the
10% ICHG condition is met again. When the input
adapter is unplugged, or the charger is disabled
and/or terminated, the leakage current from the
battery to the MP26053 is less than 1uA.
Programming of Charge Current and Battery
Full Current
The charge current (ICHG) is set by a resistor
(RCHG) connected from the ISET pin to GND.
The relationship between the charge current
and the programming resistance is established
by the following table and graph.
Table 1—RCHG and ICHG Relationship
RCHG (kΩ)
1.65
1.82
2.05
2.32
2.74
3.3
4.12
5.6
8.45
15
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© 2008 MPS. All Rights Reserved.
ICHG (mA)
1000
900
800
700
600
500
400
300
200
100
7
MP26053 – 28V, 1A LINEAR BATTERY CHARGER WITH TRICKLE CHARGE AND TIMER
Timer Operation
The TMR pin is used to set the internal
µF
. The
oscillator frequency, FOSC = 11Hz ×
CTMR
on-chip timer will start to count down after initial
power-up or every time it is enabled. This timer
will limit the max trickle-charge time to 32768
internal oscillating cycles. If the charger stays in
trickle mode for longer than 32768 cycles, it will
be terminated and a fault will be set by floating
CHG pin. After fault reporting, the charger can
be re-initiated only by recycling the power
supply or SHDN signal. If the charger
successfully goes through trickle charge within
the allowed time limit, it will start CC charging
and then CV charging. If the total charge time
exceeds 262144 cycles and the battery full has
not been qualified, the charger will be
terminated and a fault will also be set by
flashing CHG pin at the rate of half the internal
oscillation frequency. This function prevents
charging a dead battery for prolonged duration.
The timer function can be disabled by shorting
TMR to ground.
Charge Current vs.
1/RCHG
CHARGE CURRENT (mA)
1000
900
800
700
600
500
400
300
200
0
0.1 0.2 0.3 0.4 0.5 0.6 0.7
Figure 3—Charge Current vs. 1/RCHG
Resistance
The recommended resistance for programming
the charge current is 2.3kΩ