- Providing over-current protection for each of its eight sourcing
outputs, the UDN2987A and UDN2987LW drivers are used as an
interface between standard low-level logic and relays, motors, solenoids, LEDs, and incandescent lamps. The device includes thermal
shutdown and output transient protection/clamp diodes for use with
sustaining voltages to 35 V.
In these drivers, each channel includes a latch to turn OFF that
channel if the maximum channel current is exceeded. All channels are
disabled if the thermal shutdown is activated. A common FAULT
output is used to indicate either chip thermal shutdown or any overcurrent condition. All outputs are enabled by pulling the common OE/
R input high. When OE/R is low, all outputs are inhibited and the eight
latches are reset.
Under normal operating conditions, each of eight outputs will
source in excess of 100 mA continuously at an ambient temperature of
25?C and a supply of 35 V. The over-current fault circuit will protect
the device from short-circuits to ground with supply voltages of up to
35 V.
The inputs are compatible with 5 V and 12 V logic systems?TTL,
Schottky TTL, DTL, PMOS, and CMOS. In all cases, the output is
switched ON by an active high input level. The UDN2987A is supplied
in a 20-pin dual in-line plastic package; the UDN2987LW is supplied in
a 20-lead small-outline plastic package.