LTC1981/LTC1982
1
APPLICATIO S
U
DESCRIPTIO
U
FEATURES
The LTC
®
1981/LTC1982 are low-power, self-contained
N-channel MOSFET drivers. An internal voltage tripler
allows gates to be driven without the use of any external
components. Internal regulation circuitry allows quies-
cent current to drop to 10µA per driver (20µA for LTC1981)
once the gates are charged.
Low quiescent current and low shutdown current (under
1µA) make these parts ideal for battery and other power
constrained systems. The wide input voltage range ac-
commodates a variety of battery/input configurations.
Gate drive is internally clamped to 7.5V providing protec-
tion to the external MOSFET gate. The MOSFETs can be
driven in either high side or low side mode.
The LTC1981 single driver version also includes a gate
drive ready pin and twice the drive current capacity of the
dual driver LTC1982.
The LTC1981 is available in a 5-pin SOT-23. The LTC1982
is available in a 6-pin SOT-23.
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Cellular Telephones
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Portable POS Terminal
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Handheld Battery Powered Equipment
, LTC and LT are registered trademarks of Linear Technology Corporation.
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No External Components Required
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Internal Voltage Triplers Produce High Side
Gate Drive for Logic Level FETs
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Ultralow Power:
10µA Per Driver ON Current (LTC1982)
20µA ON Current (LTC1981)
<1µA Shutdown Current
■
V
CC
Range: 1.8V to 5V
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Gate Drive Outputs Driven to Ground During
Shutdown
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Gate Drive Outputs Internally Clamped to 7.5V Max
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“Gate Drive Ready” Output (LTC1981)
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Ultrasmall Application Circuit
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5-Pin SOT-23 Package (LTC1981)
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6-Pin SOT-23 Package (LTC1982)
Single and Dual Micropower
High Side Switch Controllers
in SOT-23
V
CC
GATE
SHDNGNDGDR
LTC1981
LOAD
+
10µF
GATE
DRIVE
READY
SHDN
V
CC
1.8V TO 5.0V
54
123
1981/82 TA01
100k
Q1
Si3442DV
V
CC
GATE 1 GATE 2
SHDN 1 SHDN 2GND
LTC1982
LOAD 1 LOAD 2
+
10µF
SHDN 1
SHDN 2
V
CC
1.8V TO 5.0V
654
123
1981/82 TA02
Q1
1/2 Si6925DQ
Q2
1/2 Si6925DQ
TYPICAL APPLICATIONS
U
Single High Side Switch Controller
Dual High Side Switch Controller