LTC4012-2_15 Datasheet, PDF (7/28 Pages) Linear Technology – High Efficiency, Multi-Chemistry Battery Charger with PowerPath Control

LTC4012/
LTC4012-1/LTC4012-2
Typical Performance Characteristics
(T_A = 25°C unless otherwise noted. L = IHLP-2525 6.8µH)
Charge Current Line Regulation
0.5
BAT = 6V
0.4 _{RSENSE = 33mΩ}
0.3 ^{RIN = 3.01k}
0.2
I_CHG = 1A
0.1
0
I_CHG = 2A
–0.1
I_CHG = 3A
–0.2
–0.3
–0.4
–0.5
5
10
15
20
25
DCIN PIN VOLTAGE (V)
4012 G08
Charge Current Load Regulation
3.5
I_CHG = 3A
3.0
2.5
I_CHG = 2A
2.0
1.5
I_CHG = 1A
1.0
0.5
DCIN = 20V
0 _{RSENSE = 33mΩ}
–0.5 ^{RIN = 3.01k}
11.0 11.4 11.8 12.2 12.6 13.0
BATTERY VOLTAGE (V)
4012 G09
Input Current Limit
3.0
2.5
I_IN
2.0
1.5
I_CHG
1.0
0.5 2.5A BULK CHARGE
2.1A INPUT CURRENT LIMIT
0
–0.5
ICL STATE
–1.0
0
0.5
1.0
1.5
2.0 2.5
SYSTEM LOAD (A)
4012 G10
PWM Soft-Start
I_CHG
2A/DIV
ITH
1V/DIV
PROG
1V/DIV
SHDN
5V/DIV
TIME (500µs/DIV)
4012 G11
PWM Frequency
vs Charge Current
600
500
400
CLP = 15V
300 ^RSENSE ^{= 33mΩ}
R_IN = 3.01k
200
BAT = 5V
BAT = 12V
100
BAT = 14.5V
0
0 0.5 1.0 1.5 2.0 2.5 3.0
CHARGE CURRENT (A)
4012 G14
Gate Drive Non-Overlap
BGATE
PWM Frequency vs Duty Cycle
600
I_CHG = 750mA
500
400
TGATE
TIME (80ns/DIV)
4012 G12
Battery Shutdown Current
25
DC1256-CLASS
APPLICATION
20 DCIN = 0V
15
LTC4012,
ALL PINS
10
DCIN = 0V
LTC4012,
BAT PINS
5
DCIN = 20V
0
0
5
10
15
20
25
BATTERY VOLTAGE (V)
4012 G15
300
200
100
0
0
CLP = 6V
CLP = 12V
CLP = 20V
CLP = 25V
20
40
60
80 100
DUTY CYCLE (%)
4012 G13
INFET Response Time to
DCIN Short to Ground
V_{GS =} 0V PFET V_GS (1V/DIV)
I_DCIN, REVERSE
(5A/DIV)
0A
TIME (1µs/DIV)
DCIN = 15V
INFET = Si7423DN
I_OUT = <50mA
V_OUT = 12.3V
C_OUT = 0.27F
4012 G16
4012fa