Providing improved output current limiting, the UDK, UDN, and UDQ2559B, EB, and LB quad power drivers combine AND logic gates and high-current bipolar outputs with complete output protection. Each of the four outputs will sink 700 mA in the on state. The outputs have a minimum breakdown voltage (load dump) of 60 V and a sustaining voltage of 40 V. The inputs are compatible with TTL and 5 V CMOS logic systems.
Over-current protection for each channel has been designed into these devices and is activated at approximately 1 A. It protects each output from short circuits with supply voltages up to 25 V. When an output current trip point is reached, that output stage is driven linearly resulting in a reduced output current level. If an over-current or short circuit condition continues, the thermal-limiting circuits will first sense the rise in junction temperature and then the rise in chip temperature, further decreasing the output current. Under worst-case conditions, these devices will tolerate short circuits on all outputs, simultaneously.
These devices can be used to drive various loads including incandescent lamps (without warming or limiting resistors) or inductive loads such as relays, solenoids, or dc stepping motors.
The suffix ‘B’ devices are 16-pin power DIPs, the suffix ‘EB’ devices are 28-lead power PLCCs and suffix ‘LB’ devices are 16-lead power SOICs for surface-mount applications. All three packages are of batwing construction to provide for maximum package power dissipation.

FEATURES
■ 700 mA Output Current per Channel
■ Independent Over-Current Protection for Each Driver
■ Thermal Protection for Device and Each Driver
■ Low Output-Saturation Voltage
■ Integral Output Flyback Diodes
■ TTL and 5 V CMOS Compatible Inputs
■ Pin-Compatible With UDQ2543B/EB and UDK2549B/EB