POWER SAVING IMPEDANCE TRANSFORMATION CIRCUIT FOR CCD IMAGE SENSORS

A power saving impedance transformation circuit for receiving a d-c biased signal comprises a junction transistor connected to operate as an emitter follower, means for connecting the base of the transistor to receive the signal, an operational amplifier having both inverting and non-inverting inputs, a first resistor connected between the emitter of the transistor and the operational amplifier inverting input, a second resistor equal to the first resistor in resistance and having one end connected to the operational amplifier inverting input, resistive means for connecting the other end of the second resistor to a first voltage source of a polarity which, in cooperation with the signal, forward biases the emitter-base junction of the transistor, the emitter-base junction of the transistor receiving its forward bias from the first voltage source exclusively through the first and second resistors and the resistive means, and means for connecting the collector of the transistor to a second voltage source of a polarity opposite to that of the first voltage source.