LTC3625-1_15 Datasheet, PDF (5/16 Pages) Linear Technology – 1A High Efficiency 2-Cell Supercapacitor Charger with Automatic Cell Balancing

LTC3625/LTC3625-1
Typical Performance Characteristics
T_A = 25°C, L1 = 3.3µH, L2 = 3.3µH, C_IN = 10µF, C_TOP = C_BOT , LTC3625 unless otherwise specified.
Buck Input Power vs R_PROG
8
7
I_PROG
CLAMPED
V_IN = 5.5V
V_MID = 2.65V
CTL = 0V
6
V_SEL = V_IN
5
4
3
2
1
0
0 50 100 150 200 250 300 350 400 450 500
R_PROG (kΩ)
3625 G05
Buck Efficiency vs I_BUCK
100
95
90
85
80
75
70
65
60 _{VIN = 3.6V}
55 ^VMID ^{= 2V}
CTL = 0V
50
200
700
1200 1700
I_BUCK (mA)
2200
3625 G06
Buck Efficiency vs V_MID
100
V_IN = 5.5V
V_SEL = V_IN
90 _{CTL = 0}
80
R_PROG = 71.5k
70
R_PROG = 143k
R_PROG = 286k
60
50
40
0.2 0.6 1.0 1.4 1.8
V_MID (V)
2.2 2.6
3625 G08
Boost Efficiency vs V_TOP
90
NORMAL OPERATION
80
70
60
V_OUT TRICKLE
CHARGE OPERATION
50
40
30
20
–1.5 –1.0 –0.5
V_IN = 3.6V
V_MID = 2.5V
V_TOP = V_OUT – V_MID
CTL = 0
0 0.5 1.0 1.5 2.0 2.5
V_TOP (V)
3625 G11
Buck Output Current vs V_MID
2500
2250
2000
R_PROG = 71.5k
1750
1500
1250
1000
R_PROG = 143k
750
R_PROG = 286k
500 _{VIN = 5.5V}
250 VSEL = VIN
CTL = 0
0
0.2 0.6 1.0 1.4 1.8 2.2 2.6
V_MID (V)
3625 G09
RFET vs Temperature
0.20
0.25
0.15
0.20
PMOS
0.10
0.15
NMOS
0.05
0.10
0
–40 –25 –10 5
V_IN = 2.7V
V_IN = 5.5V
0.05
20 35 50 65 80 95 110 125
TEMPERATURE (°C)
3625 G12
Buck Input Power vs V_MID
6
V_IN = 5.5V
V_SEL = V_IN
5 _{CTL = 0}
4
R_PROG = 71.5k
3
R_PROG = 143k
2
R_PROG = 286k
1
0
0.2 0.6 1.0 1.4 1.8
V_MID (V)
2.2 2.6
3625 G07
Boost Input Current vs V_TOP
2500
2000
1500
NORMAL OPERATION
1000
V_OUT
500 TRICKLE
CHARGE
OPERATION
0
–1.5 –1.0 –0.5
V_IN = 3.6V
V_MID = 2.5V
V_TOP = V_OUT – V_MID
CTL = 0
0 0.5 1.0 1.5 2.0 2.5
V_TOP (V)
3625 G10
Charge Time vs R_PROG
400
V_IN = 3.6V
350 ^VSEL ^{= 3.6V}
V_OUT INITIAL = 0V
300 ^CTOP ^{= C}BOT ^{= 10F}
250
SINGLE
200 INDUCTOR
APPLICATION
150
100 _IPROG
50 ^CLAMPED
DUAL
INDUCTOR
APPLICATION
0
0 50 100 150 200 250 300 350 400 450 500
R_PROG (kΩ)
3625 G15
3625f