Datasheet

LTC4253B
3
4253bf
elecTrical characTerisTics
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 2)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
Z
V
IN
– V
EE
Zener Voltage I
IN
= 2mA
●
11.5 13 14.5 V
R
Z
V
IN
– V
EE
Zener Dynamic Impedance I
IN
= (2mA to 30mA) 5 Ω
I
IN
V
IN
Supply Current UV = OV = 4V, V
IN
= (V
Z
– 0.3V)
●
0.8 2 mA
V
LKO
V
IN
Undervoltage Lockout Coming Out of UVLO (Rising V
IN
)
●
9.2 11.5 V
V
LKH
V
IN
Undervoltage Lockout Hysteresis
●
0.5 1 1.5 V
V
IH
TTL Input High Voltage
●
2 V
V
IL
TTL Input Low Voltage
●
0.8 V
V
HYST
TTL Input Buffer Hysteresis 600 mV
I
RESET
RESET Input Current V
EE
≤ V
RESET
≤ V
IN
●
±0.1 ±10 µA
I
EN
EN2, EN3 Input Current V
EN
= 4V
V
EN
= 0V
●
●
60 120
±0.1
180
±10
µA
µA
V
CB
Circuit Breaker Current Limit Voltage V
CB
= (V
SENSE
– V
EE
)
●
40 50 60 mV
V
ACL
Analog Current Limit Voltage V
ACL
= (V
SENSE
– V
EE
), SS = Open or 2.2V
●
80 100 120 mV
V
FCL
Fast Current Limit Voltage V
FCL
= (V
SENSE
– V
EE
)
●
150 200 300 mV
V
SS
SS Voltage After End of SS Timing Cycle
●
2 2.2 2.4 V
I
SS
SS Pin Current UV = OV = 4V, V
SENSE
= V
EE,
V
SS
= 0V (Sourcing)
●
12 22 32 µA
UV = OV = 0V, V
SENSE
= V
EE,
V
SS
= 1V (Sinking)
28 mA
R
SS
SS Output Impedance 100 kΩ
V
OS
Analog Current Limit Offset Voltage 10 mV
V
ACL
+ V
OS
V
SS
Ratio (V
ACL
+ V
OS
) to SS Voltage 0.05 V/V
I
GATE
GATE Pin Output Current UV = OV = 4V, V
SENSE
= V
EE
,
V
GATE
= 0V (Sourcing)
●
30 50 70 µA
UV = OV = 4V, V
SENSE
– V
EE
= 0.15V,
V
GATE
= 3V (Sinking)
17 mA
UV = OV = 4V, V
SENSE
– V
EE
= 0.3V,
V
GATE
= 1V (Sinking)
190 mA
V
GATE
External MOSFET Gate Drive V
GATE
– V
EE,
I
IN
= 2mA
●
10 12 V
Z
V
V
GATEL
Gate Low Threshold Before Gate Ramp Up 0.5 V
V
GATEH
Gate High Threshold V
GATEH
= V
IN
– V
GATE
, for PWRGD1,
PWRGD2, PWRGD3 Status
2.8 V
V
UVHI
UV Pin Threshold HIGH UV Low to High
●
3.075 3.225 3.375 V
V
UVLO
UV Pin Threshold LOW UV High to Low
●
2.775 2.925 3.075 V
V
UVHST
UV Pin Hysteresis 230 300 350 mV
V
OVHI
OV Pin Threshold HIGH OV Low to High
●
5.85 6.15 6.45 V
V
OVLO
OV Pin Threshold LOW OV High to Low
●
5.55 5.85 6.15 V
V
OVHST
OV Pin Hysteresis 230 300 350 mV
I
SENSE
SENSE Pin Input Current UV = 0V = 4V, V
SENSE
= 50mV (Sourcing)
●
15 30 µA
I
INP
UV, OV Pin Input Current UV = OV = 4V
●
±0.1 ±1 µA
V
TMRH
TIMER Pin Voltage High Threshold
●
3.5 4 4.5 V