Drive circuit

Abstract

Abstract PURPOSE:To detect whether or not the load state such as load short-circuit or load open is normal or abnormal by providing 1st and 2nd comparator circuits. CONSTITUTION:A comparator circuit 8, a reference voltage source 7, a comparator circuit 9, a reference voltage source 10, an OR circuit 11 outputting an OR between outputs of the comparator circuits 8, 9 and a detection circuit comprising a resistor R9 and a transistor (TR) Q7 are connected to an output terminal 3 and a TR Q1. An output of the OR circuit 11 is a high level with respect to a normal load when an input signal is at a high level if a load resistor RL is abnormal such as short-circuit or open circuit. Thus, the output current is controlled to be constant when the impedance of the load resistor RL is decreased abnormally and abnormal load such as load short-circuit and load open is detected.

Inventors

• 👤 Kazuhiro Mori
• 👤 森　数洋
• 👤 Shigekazu Miyake
• 👤 重和 三宅

Bibliographic Details