LT1032_02 Datasheet, PDF (6/12 Pages) Linear Technology – Quad Low Power Line Driver

LT1032
APPLICATI S I FOR ATIO
Application Hints
The LT1032 is exceptionally easy to use when compared
to older drivers. Operating supply voltage can be as low as
±3V or as high as ±15V. Input levels are referred to ground.
The logic inputs are internally set at TTL levels. Outputs are
valid for input voltages from 1V above V ^– to 25V. Driving
the logic inputs to V ^– turns off the output stage. The
ON/OFF control completely turns off all supply current of
the LT1032. The levels required to drive the device on or
off are set by internal emitter-based voltages. Since the
current into the ON/OFF pin is so low, TTL or CMOS drivers
have no problem controlling the device.
The strobe pin is not fully logic compatible. The impedance
of the strobe pin is about 2kΩ to ground. Driving the strobe
pin positive forces the output stages low–even if the device
is shut off. Under worst case conditions, 3V minimum at
2mA are needed driving the strobe pin to insure strobing.
The response pin can be used to make some adjustment
in slew rate. A resistor can be connected between the re-
sponse pin and the power supplies to drive 50µA to 100µA
into the pin. The response pin is a low impedance point
operating at about 0.75V above ground. For supply voltage
up to ±6V, current is turned off when the device is turned
off. For higher supply voltages, a Zener should be con-
nected in series with the resistor to limit the voltage applied
to the response pin to 6V. Also, for temperatures above
100°C, using the response pin is not recommended. The
leakage current into the response pin at high temperatures
is excessive.
Outputs are well protected against shorts or externally
applied voltage. Tested limits are ±30V, but the device can
withstand external voltages up to breakdown of the tran-
sistors (typically about 50V). The LT1032 is usually immune
to ESD up to 2500V on the outputs with no damage.
TYPICAL APPLICATI S
Protecting Against More Than ±30V Output Overload
V⁺
INPUT
1/4 LT1032
100Ω TO
1000Ω
TO LINE
INPUT
1/4 LT1032
V^–
LT1032 • TA03a
TO LINE
30V ZENERS
LT1032 • TA03b
FET Driver
15V
INPUT
1/4 LT1032
– 15V
50k
LT1032 • TA04
6
Slew Rate Adjustment*
5V
80k
10V ^†
80k
15V
50µA
INCREASES
SLEW RATE
LT1032 PIN 10 OR
OR
120k 120k
50µA
DECREASES
SLEW RATE
– 5V
*ABOUT 4V/ms CHANGE
10V ^†
†_{ZENERS PREVENT LEAKAGE DURING SHUTDOWN}
– 15V
LT1032 • TA05
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