| 摘要 |
PURPOSE:To compensate both the temperature and power supply voltage dependent properties of the output reference voltage, by combining two reference voltage generating circuits consisting of a pair of differential MISFETs respectively. CONSTITUTION:The size and drain currents are set equal to each other for a pair of differential MISFETQ1 and Q2 having different levels of threshold voltage. Thus the 1st reference voltage generating circuit is obtained to generate the 1st reference voltage Vref1 which is equal to the difference between both threshold voltages. In the same way, the 2nd reference voltage generating circuit is formed to generate the 2nd reference voltage Vref2. Then the size and drain current ratios are set between differential MISFETQ'1 and Q'2 so as to eliminate the temperature characteristics of the 1st reference voltage. The bias current I'0 of the 2nd reference voltage generating circuit is obtained from the voltage Vref1. Then the 2nd reference voltage generating circuit is actuated to obtain the voltage Vref2. In such a way, both the temperature and power supply voltage dependent properties can be compensated. |
