Solid-state image pickup device including switched capacitor amplifier
A solid-state image pickup device includes a detection diode for detecting a transfer charge and a switched capacitor amplifier whose input section is connected to the detection diode. The switched capacitor amplifier includes an inverting amplifier, a reset transistor and a feedback capacitor which are connected between input and output sections of the inverting amplifier. Thus, the solid-state image pickup device satisfies the requirements for both improvement in charge-voltage conversion efficiency and reduction in generated noises.
1. A solid-state image pickup device comprising:
a plurality of photoelectric conversion elements;
a plurality of charge transfer elements for transferring photoelectric charge generated in the plurality of photoelectric conversion elements;
a detection diode for detecting the photoelectric charge transferred by the plurality of charge transfer elements; and
a switched capacitor amplifier whose input section is connected to the detection diode, wherein the switched capacitor amplifier includes:
an inverting amplifier whose input section is connected to the detection diode;
a reset transistor connected between an input section and an output section of the inverting amplifier; and
a capacitor connected between the input section and the output section of the inverting amplifier and parallel to the reset transistor, and
a gate application pulse generation circuit for generating a gate application pulse of the reset transistor, wherein
the gate application pulse generation circuit includes:
a second inverting amplifier of a structure identical to that of the inverting amplifier of the switched capacitor amplifier; and
a second reset transistor of a structure identical to that of the reset transistor of the switched capacitor amplifier.
2. The solid-state image pickup device as claimed in claim 1 , wherein
an input section and an output section of the second inverting amplifier are connected together
a drain and a gate of the second reset transistor are connected together,
the drain and source of the second reset transistor are connected together through a high resistance resistor
the output section of the second inverting amplifier and the source of the second reset transistor are connected together, and
the gate of the reset transistor of the switched capacitor amplifier is connected to the drain of the second reset transistor.