Datasheet
LTC1155
4
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For more information www.linear.com/LTC1155
TYPICAL PERFORMANCE CHARACTERISTICS
Standby Supply Current Supply Current Per Side (ON) Input ON Threshold
Turn ON Time Turn OFF Time Short-Circuit Turn OFF Delay Time
SUPPLY VOLTAGE (V)
0
0
TURN-ON TIME (µs)
600
700
800
900
1000
5 10 20
1155 G07
100
200
300
400
500
15
C
GATE
= 1000pF
V
GS
= 5V
V
GS
= 2V
SUPPLY VOLTAGE (V)
0
0
TURN OFF TIME (µs)
30
35
40
45
50
5 10 20
1155 G08
5
10
15
20
25
15
C
GATE
= 100pF
TIME FOR V
GATE
< 1V
SUPPLY VOLTAGE (V)
0
0
TURN-OFF TIME (µs)
30
35
40
45
50
5 10 20
1155 G09
5
10
15
20
25
15
V
SEN
= V
S
–1V
NO EXTERNAL DELAY
C
GATE
= 1000pF
TIME FOR V
GATE
< 1V
TEMPERATURE (°C)
–50
0
SUPPLY CURRENT (µA)
5
10
25
35
40
50
–25 0 25 50
1155 G10
15
20
30
45
75 100 125
V
S
= 5V
V
S
= 18V
TEMPERATURE (°C)
–50
0
SUPPLY CURRENT (µA)
100
200
500
700
800
1000
–25 0 25 50
1155 G11
300
400
600
900
75 100 125
V
S
= 12V
V
S
= 5V
TEMPERATURE (°C)
–50
0.4
INPUT THRESHOLD (V)
0.6
0.8
1.4
1.8
2.0
2.4
–25 0 25 50
1155 G12
1.0
1.2
1.6
2.2
75 100 125
V
S
= 18V
V
S
= 5V
PIN FUNCTIONS
Input Pin
The LTC1155 logic input is a high impedance CMOS gate
and should be grounded when not in use. These input
pins have ESD protection diodes to ground and supply
and, therefore, should not be forced beyond the power
supply rails.
Gate Drive Pin
The gate drive pin is either driven to ground when the
switch is turned OFF or driven above the supply rail
when
the switch is turned ON. This pin is a relatively high imped-
ance when driven above the rail (the equivalent of a few
hundred kΩ). Care should be taken to minimize any loading
of this pin by parasitic resistance to ground or supply.
Supply Pin
The supply pin of the LTC1155 serves two vital purposes.
The first is obvious: it powers the input, gate drive, regula-
tion and protection circuitry. The second purpose is less
obvious: it provides a Kelvin connection to the top of the
two drain sense resistors for the internal 100mV reference.
The supply pin should be connected directly to the power
supply source as close as possible to the top of the two
sense resistors.