| 摘要 |
<p>PURPOSE:To process both a high voltage and a low voltage without influence to an operating margin by providing sense amplifiers for high and low voltages on the same board, and selecting the output of the amplifier by a selector. CONSTITUTION:The voltage of a battery 22 to be used is detected by a sensor 21. If it is a high voltage, a mode setter 23 sets a selection signal SEL to a high level so as to drive a sense amplifier 17 for a high voltage. When the sensor 21 detects a low voltage, the setter 23 sets the signal SEL to a low level so as to drive a sense amplifier 18 for a low voltage. A flip-flop 20 holds the output signal of the setter 23, outputs a selection signal/SEL inverted through an inverter 19 to the amplifier 17, and outputs a selection signal to an amplifier 18.</p> |
