Application of Bipolar Technology to the Seatbelt Interlock System

Bipolar integrated circuit technology can make important contributions to automotive electronics by combining digital and analog low current drain circuitry with relatively high current drive capability. This seatbelt-interlock module design consists of a 200-component logic integrated circuit designed with low threshold TTL drawing a nominal 3 milliamps and a driver integrated circuit which sinks up to 2 amperes steady state and 8 amperes surge. Integrated circuit protection is provided by 16 external discrete components.