| 摘要 |
PURPOSE:To prevent the useless power consumption which is caused by an increment of the power consumption of the amplifier due to the noise or the like for a radio receiver or the like with a memory function incorporating the circuit which receives an application of the power supply voltage even when the power supply switch is off, by fixing the voltage at a certain level for the input terminal of the amplifier in the above-mentioned circuit at the moment when the power supply switch is turned off. CONSTITUTION:The output frequency data given from the IC circuit 1 which delivers the frequency data of the radio reception signal is received by the LSI2 and then amplified by the linear amplifiers A1 and A2 to be stored in the memory M. The power supply terminal 2a is always connected to the power source 3 to avoid an erasion of the memory contents of the memory M. When the power supply switch 9 is off, the bias current flows to the transistors 4 and 5 via the emitter base and the resistance 6. As a result, the transistors 4 and 5 are saturated, and the voltage of the source 3 is applied to the input terminals 2b1 and 2b2 of the LSI2. Then the outputs of the linear amplifiers A1 and A2 are fixed by the terminals 2b1 and 2b2 which are clamped at the H level. Thus the amplifiers A1 and A2 have no operation even by the noise to prevent the useless power consumption. |
