LTC3625-1_15 Datasheet, PDF (4/16 Pages) Linear Technology – 1A High Efficiency 2-Cell Supercapacitor Charger with Automatic Cell Balancing

LTC3625/LTC3625-1
Electrical Characteristics
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3625/LTC3625-1 internal switches are guaranteed to
survive up to 3A of peak current. Internal current limits will restrict peak
current to lower levels.
Note 3: The LTC3625/LTC3625-1 are tested under pulsed load conditions
such that T_J ≈ T_A. The LTC3625E/LTC3625E-1 are guaranteed to meet
specifications from 0°C to 85°C junction temperature. Specifications over
the –40°C to 125°C operating junction temperature range are assured by
design, characterization and correlation with statistical process controls.
The LTC3625I/LTC3625I-1 are guaranteed over the –40°C to 125°C
operating junction temperature range.
The junction temperature (T_J in °C) is calculated from the ambient
temperature (T_A in °C) and power dissipation (P_D in Watts) according to
the formula:
T_J = T_A + (P_D • θ_JA)
where θ_JA (in °C/W) is the package thermal impedance.
Note 4: This IC includes overtemperature protection that is intended to
protect the device during momentary overload conditions. The maximum
rated junction temperature will be exceeded when this protection is active.
Continuous operation above the specified maximum operating junction
temperature may impair device reliability or permanently damage the
device.
Note 5: Measurements are tested with CTL = 0V.
Typical Performance Characteristics
T_A = 25°C, L1 = 3.3µH, L2 = 3.3µH, C_IN = 10µF, C_TOP = C_BOT , LTC3625 unless otherwise specified.
Charge Termination Error
vs Temperature
2.0
V_IN = 3.6V
1.5
1.0
0.5
SLEEP THRESHOLD
0
WAKE THRESHOLD
–0.5
–1.0
–1.5
–2.0
–40 –25 –10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
3625 G13
PROG Voltage and PFI Falling
Threshold vs Temperature
1.220
V_IN = 3.6V
1.215 ^RPROG ^{= 143k}
1.210
1.205
1.200
1.195
1.190
1.185
1.180
–40 –25 –10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
3625 G02

Input and Output Sleep Currents
vs Temperature
25
V_IN = 3.6V
V_SEL = 3.6V
20
LTC3625 I_VOUT
V_OUT = 5.3V
15
LTC3625-1 I_VOUT
V_OUT = 4.5V
10
I_VIN
5
0
–40 –25 –10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
3625 G14
Buck Current Limits
vs Temperature
1200
1150
I_PEAK
1100
1050
1000
950
I_VALLEY
900
850 V_IN = 3.6V
R_PROG = 143k
800
–40 –25 –10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
3625 G03
Sleep Current vs V_IN
25
V_OUT = 4.8V
V_SEL = 0V
20
I_VOUT
15
10
I_VIN
5
0
2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5
V_IN (V)
3625 G01
Buck Output Current vs R_PROG
3000
2500
I_PROG
CLAMPED
V_IN = 3.6V
V_MID = 2V
CTL = 0V
2000
1500
1000
500
0
0 50 100 150 200 250 300 350 400 450 500
R_PROG (kΩ)
3625 G04
3625f