Datasheet

3
4251b12f
LTC4251B/LTC4251B-1/
LTC4251B-2
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.
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
GATEL
Gate Low Threshold (Before Gate Ramp-Up) 0.5 V
V
UVHI
UV Threshold High LTC4251B/LTC4251B-2
LTC4251B-1
l
l
3.075
2.300
3.225
2.420
3.375
2.540
V
V
V
UVLO
UV Threshold Low LTC4251B/LTC4251B-2
LTC4251B-1
l
l
2.775
2.050
2.925
2.160
3.075
2.270
V
V
V
UVHST
UV Hysteresis LTC4251B/LTC4251B-2
LTC4251B-1
0.30
0.26
V
V
V
OVHI
OV Threshold High LTC4251B
LTC4251B-1
l
l
5.85
5.86
6.15
6.17
6.45
6.48
V
V
V
OVLO
OV Threshold Low LTC4251B
LTC4251B-1
l
l
5.25
5.61
5.55
5.91
5.85
6.21
V
V
V
OVHST
OV Hysteresis LTC4251B
LTC4251B-1
0.60
0.26
V
V
I
SENSE
SENSE Input Current UV/OV = 4V, V
SENSE
= 50mV
l
–30 –15 μA
I
INP
UV/OV Input Current UV/OV = 4V
l
±0.1 ±1 μA
V
TMRH
Timer Voltage High Threshold 4V
V
TMRL
Timer Voltage Low Threshold 1V
I
TMR
Timer Current Timer On (Initial Cycle, Sourcing), V
TMR
= 2V
Timer Off (Initial Cycle, Sinking), V
TMR
= 2V
Timer On (Circuit Breaker, Sourcing), V
TMR
= 2V
Timer Off (Cooling Cycle, Sinking), V
TMR
= 2V
5.8
28
230
5.8
μA
mA
μA
μA
t
PLLUG
UV Low to GATE Low 0.7 μs
t
PHLOG
OV High to GATE Low LTC4251B/LTC4251B-1 1 μs
V
IN
(V)
024 6810121416182022
I
IN
(mA)
1000
100
10
1
0.1
4251b12 G02
T
A
= –40°C
T
A
= 125°C
T
A
= 25°C
T
A
= 85°C
I
IN
vs Temperature
I
IN
vs V
IN
r
Z
vs Temperature
UV/OV = 4V refers to UV = 4V for the LTC4251B-2.
Note 2: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to V
EE
unless otherwise
specified.
Note 3: UV/OV = 4V refers to UV = 4V for the LTC4251B-2.
TYPICAL PERFORMANCE CHARACTERISTICS
TEMPERATURE (°C)
–55
I
IN
(μA)
2000
1800
1600
1400
1200
1000
800
600
400
200
0
–15
25
45 125
4251b12 G01
–35 5
65
85
105
V
IN
= (V
Z
– 0.3V)
TEMPERATURE (°C)
–55
r
Z
(Ω)
10
9
8
7
6
5
4
3
2
–15
25
45 125
4251b12 G03
–35 5
65
85
105
I
IN
= 2mA