PURPOSE: To set the hysteresis voltage over a wide range and to decrease the temperature dependancy by connecting a resistor between emitter of both transistors (TR) and decreasing the current of the emitter current source of the TR turned off.

CONSTITUTION: When an input voltage Vi is large enough to cut off a TR Q2, an output current I2 of a current mirror circuit 15 is expressed as I2=IR=nIR =0 and the output current IL of the current mirror circuit 14 is expressed as IL=I1. A TR Q4 gives a current nLIL to a resistor R2 and a TR Q12 is cut off. Thus, no current flows to a resistor RE. When the input voltage Vi is decreased, an output current I2 starts flowing to the TR Q2 through the resistor RE, but the TR Q9 is saturated while I2<I1, and the output current IR flows when I2<I1, then the current nRIR flows to the resistor Rl to decrease a current Iref1 thereby inverting the state.