公开(公告)号：US5291365A

公开(公告)日：1994-03-01

申请号：US964632

申请日：1992-10-22

Applicant: Nobutomo Takagi

Inventor： Nobutomo Takagi

IPC: G06F1/26 ,  B60R16/02 ,  B60R16/03 ,  G05F1/569 ,  H02H3/20 ,  H02H9/04

CPC classification number: H02H9/046 ,  G05F1/569 ,  B60R16/03

Abstract: First, second, and third power supply lines are separate from each other. A power supply circuit receives electric power from the first power supply line, and generates a given power supply voltage from the received electric power and outputs the generated power supply voltage to the third power supply line. An electronic circuit is connected to the third power supply line to be activated by the power supply voltage. The electronic circuit has an input section for receiving an input signal from the second power supply line. A protective circuit provided in the electronic circuit leaks a current from the input section of the electronic circuit toward the third power supply line when a voltage of the input signal exceeds the power supply voltage. A reference voltage generating device serves to generate a first reference voltage in the presence of the electric power fed from the first power supply line to the power supply circuit, and serves to generate a second reference voltage in the absence of the electric power fed from the first power supply line to the power supply circuit. The second reference voltage is lower than the first reference voltage. A voltage limiting device being responsive to the first and second reference voltages serves to limit a voltage of the third power supply line to below a level approximately equal to the first or second reference voltage.

Abstract translation: 第一，第二和第三电源线彼此分开。 电源电路从第一电源线接收电力，并从接收的电力产生给定的电源电压，并将生成的电源电压输出到第三电源线。 电子电路连接到第三电源线，由电源电压激活。 电子电路具有用于从第二电源线接收输入信号的输入部。 设置在电子电路中的保护电路当输入信号的电压超过电源电压时，从电子电路的输入部向第三电源线泄漏电流。 参考电压产生装置用于在存在从第一电源线馈送到电源电路的电力的情况下产生第一参考电压，并且用于在不存在从第一电源线馈送的电力的情况下产生第二参考电压 第一个供电线路供电电路。 第二参考电压低于第一参考电压。 响应于第一和第二参考电压的电压限制装置用于将第三电源线的电压限制在低于大约等于第一或第二参考电压的电平。