| 摘要 |
PURPOSE:To make it possible to obtain a direct-current bias capable of canceling variation in circuit operation due to variation in power voltage, etc., by providing a voltage divider circuit composed of IG-FET and an amplifier which inverts and amplifies divided voltages. CONSTITUTION:The voltage divider circuit consists of enhancement IG-FETs 11 and 13 and depletion IG-FET12, and the amplifier circuit which inverts and amplifies divided voltage (a) consists of enhancement IG-FETs 14 and 15; a voltage at connection point (b) is applied as a direct-current bias to the circuit formed in the same substrate as those circuit. Next, when direct-current applied voltage VDD becomes higher than a normal value, the voltage at point (a) rises and voltage V(b) at point (b) falls linearly according to variation in VDD. Namely, since direct- current bias V(b) varies to cancel variation in VDD, even if caused, variance in operation of the IG-FET circuit applied with this direct-current bias is canceled. When threshold voltage Vth of FETs 11 to 13 varies, it is canceled in the same way. |
