The ULx200xA devices are high-voltage, high-current
Darlington transistor arrays. Each consists of seven
NPN Darlington pairs that feature high-voltage outputs
with common-cathode clamp diodes for switching
inductive loads.
The collector-current rating of a single Darlington pair
is 500 mA. The Darlington pairs can be paralleled
for higher current capability. Applications include
relay drivers, hammer drivers, lamp drivers, display
drivers (LED and gas discharge), line drivers, and
logic buffers. For 100-V (otherwise interchangeable)
versions of the ULx2003A devices, see the SLRS023
data sheet for the SN75468 and SN75469 devices.
The ULN2002A device is designed specifically for use
with 14-V to 25-V PMOS devices. Each input of this
device has a Zener diode and resistor in series to
control the input current to a safe limit. The ULx2003A
devices have a 2.7-kΩ series base resistor for each
Darlington pair for operation directly with TTL or 5-V
CMOS devices.
The ULx2004A devices have a 10.5-kΩ series base
resistor to allow operation directly from CMOS
devices that use supply voltages of 6 V to 15 V.
The required input current of the ULx2004A device is
below that of the ULx2003A devices, and the required
voltage is less than that required by the ULN2002A
device.
