| 摘要 |
PURPOSE:To enhance detection accuracy, by providing voltage generation parts each for multiplying the differential voltage of voltages (VBE) between base emitters of plural transistors (TR) by a resistance ratio to both of reference voltage and IC chip temp. detecting voltage generation circuits and calculating the difference between outputs of both circuits. CONSTITUTION:The bases of TRQ2 and TRQ3 are connected in common and the differential voltage DELTAVVEI of voltage VBE is applied to both terminals of a current converting resistors R1. The voltages (Vr) at both terminals of the resistor R2 connected to the collector of TRQ3 detects the temp. of an IC chip and is multiplied by R2/R1 to be inputted to the positive terminal of a comparator 4. The bases of TRQ4 and TR Q2, Q3 are connected in common and the differential voltage DELTAVBE2 of voltages VBE of TR Q2, Q4 is applied to both terminals of a resistor R3. The voltage between the resistor R4 in the collector side of TRQ4 and a diode Q5 is inputted to the negative terminal of the comparator 4 as reference voltage Vref with temp. coefficient of 0. When circumferential temp. is raised, Vr increases and the comparator 4 outputs a low level to limit the operation of the other IC circuit in the same chip. By this method, the rising in temp. is accurately detected. |
