LT1640AH_15 Datasheet, PDF (4/16 Pages) Linear Technology – Negative Voltage Hot Swap Controller

LT1640AL/LT1640AH
TYPICAL PERFOR A CE CHARACTERISTICS
Gate Voltage vs Temperature
15.0
V_DD = 48V
14.5
14.0
13.5
13.0
12.5
12.0
– 50 – 25 0 25 50
TEMPERATURE (°C)
75 100
1640A G04
Gate Pull-Down Current
vs Temperature
55
V_GATE = 2V
52
49
46
43
40
– 50 – 25 0
25 50 75 100
TEMPERATURE (°C)
1640A G07
Circuit Breaker Trip Voltage
vs Temperature
55
54
53
52
51
50
49
48
– 50 – 25
0 25 50
TEMPERATURE (°C)
75 100
1640A G05
PWRGD Output Low Voltage
vs Temperature (LT1640AL)
0.5
I_OUT = 1mA
0.4
0.3
0.2
0.1
0
– 50 – 25
0 25 50
TEMPERATURE (°C)
75 100
1640A G08
Gate Pull-Up Current
vs Temperature
48
V_GATE = 0V
47
46
45
44
43
42
41
40
– 50
– 25 0 25 50
TEMPERATURE (°C)
75 100
1640A G06
PWRGD Output Impedance
vs Temperature (LT1640AH)
8
V_DRAIN – V_EE > 2.4V
7
6
5
4
3
2
– 50 – 25 0 25 50
TEMPERATURE (°C)
75 100
1640A G09
PI FU CTIO S
PWRGD/PWRGD (Pin 1): Power Good Output Pin. This pin
will toggle when V_DRAIN is within V_PG of V_EE. This pin can
be connected directly to the enable pin of a power module.
When the DRAIN pin of the LT1640AL is above V_EE by
more than V_PG, the PWRGD pin will be high impedance,
allowing the pull-up current of the module’s enable pin to
pull the pin high and turn the module off. When V_DRAIN
drops below V_PG, the PWRGD pin sinks current to V_EE,
pulling the enable pin low and turning on the module.
When the DRAIN pin of the LT1640AH is above V_EE by
more than V_PG, the PWRGD pin will sink current to the
DRAIN pin which pulls the module’s enable pin low,
forcing it off. When V_DRAIN drops below V_PG, the PWRGD
sink current is turned off and a 6.5k resistor is connected
between PWRGD and DRAIN, allowing the module’s pull-
up current to pull the enable pin high and turn on the
module.
4