| 摘要 |
PURPOSE:To make it possible to realize a function for reducing power consumption under holding state with a small number of circuit elements by constituting a holding circuit of a current feedback amplifier comprising a transistor receiving a reference voltage and operating with a constant current. CONSTITUTION:When an input IN is L level under holding state, a switch SW11 selects contact (a) while switch SW21 selects contact (b) and a switch 12 closes while a switch 22 opens. On the other hand, transistors N31, P32 are turned OFF while transistors P31 N32 are turned ON. Consequently, the output terminal O2 of a push-pull circuit 32 has a voltage level vO2 equal to the voltage level vS of the ground VS. Potential at the gate of a transistor N11 in a holding circuit 1 is equal to a voltage reference VR and the voltage level vO1 at the output terminal of a push-pull circuit 31 can be shown by a formula, where (i) is the current value of a constant current supply IS11, beta is the gain factor of the transistor N11, and VT is a threshold voltage. According to the constitution, power can be saved. |
