Specifications

LTC4056-4.2
3
405642f
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
∆V
RECHRG
Recharge Threshold Voltage V
FLOAT
– V
RECHRG
, V
BAT
> V
TRIKL
, 100 150 200 mV
Charge Termination Timer Expired
T
TIMER
TIMER/SHDN Accuracy C
TIMER
= 1µF R
PROG
= 1.43k ● 10 12 %
Charger Manual Control
V
MSDT
Manual Shutdown Threshold Voltage V
TIMER/SHDN
Increasing ● 0.6 0.82 1 V
V
MSHYS
Manual Shutdown Hysteresis Voltage V
TIMER/SHDN
Decreasing 50 75 125 mV
I
SHDN
TIMER/SHDN Pin Pull-up Current V
TIMER/SHDN
= 0V –10 –7 –4 µA
Protection
I
DSHRT
Drive Output Short-Circuit Current Limit V
DRIVE
= V
CC
● 30 65 130 mA
I
PSHRT
PROG Pin Short-Circuit Current Limit V
PROG
= 0V 1.4 mA
Status Output
I
CHRG
CHRG Pin Weak Pull-Down Current V
CHRG
= 1V, V
TIMER/SHDN
= 0V 6 12 18 µA
V
CHRG
CHRG Output Low Voltage I
CHRG
= 10mA ● 0.2 0.4 V
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LTC4056E is guaranteed to meet performance specifications
from 0°C to 70°C ambient temperature range. Specifications over the
–40°C to 85°C operating ambient temperature range are assured by
design, characterization and correlation with statistical process controls.
Note 3: Although the LTC4056 will operate with input voltages as low as
4.5V, charging will not begin until V
CC
exceeds V
UVCL
.
Note 4: Assumes that the external PNP pass transistor has negligible B-C
reverse-leakage current when the collector is biased at 4.2V (V
BAT
) and the
base is biased at 5V (V
CC
).
Note 5: Assumes that the external PNP pass transistor has negligible B-E
reverse-leakage current when the emitter is biased at 0V (V
CC
) and the
base is biased at 4.2V (V
BAT
).
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Float Voltage vs Temperature and
Supply Voltage
TEMPERATURE (°C)
–50
V
FLOAT
(V)
4.205
4.210
4.215
25 75
4056-4.2 G01
4.200
4.195
–25 0
50 100 125
4.190
4.185
I
BAT
= 10mA
PNP = FZT749
V
CC
= 6.5V
V
CC
= 4.75V
I
BAT
(mA)
0
FLOAT VOLTAGE (V)
300
4056-4.2 G02
4.200
4.199
100 200 400
4.198
4.202
4.201
500 600 700
V
CC
= 5V
T
A
= 25°C
PNP = FZT749
R
PROG
= 1.30k
TEMPERATURE (°C)
–50
I
BAT
(mA)
215
25
4056-4.2 G03
200
190
–25 0 50
185
180
220
210
205
195
75 100 125
R
PROG
= 4.53k
PNP = FZT749
V
CC
= 6.5V
V
CC
= 4.75V
Float Voltage vs I
BAT
I
BAT
vs Temperature and
Supply Voltage