Title:
ANALOG SIGNAL AMPLIFIER AND SOLID-STATE IMAGE-PICKUP ELEMENT CONTAINING THE SAME
Document Type and Number:
Japanese Patent JP3558516
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain a specified voltage amplification ratio, to set dispersions to be small and to prevent the occurrence of a fixed output distribution, while maintaining the feature of a low output impedance by feeding back changes in the output potential of a source follower amplifier to its input through a feedback capacitance.
SOLUTION: A power switch 21 is provided at the drain electrode-side of the driver transistor 10 of a source follower amplifier, and a sample-and-hold circuit is provided at a terminal connected to the gate electrode of the driver transistor 10, namely, an input terminal. An input signal is supplied to the sample-and-hold circuit in a state, in which the power switch 21 is turned off and the value is held. When the power switch 21 is turned on, an output potential is fed back to its input through a feedback capacitance 23 with the rise of the output potential of the source follower amplifier, and the voltage amplification ratio becomes not less than '1'. Since the amplification ratio is determined by the ratio of sample-and-hold capacity 9 to the feedback capacity 23, a plurality of ratios may be provided for respective columns in a sold-state image-pickup element by rows.
Inventors:
Masashi Ueno
Application Number:
JP1238398A
Publication Date:
August 25, 2004
Filing Date:
January 26, 1998
Export Citation:
Assignee:
Mitsubishi Electric Corporation
International Classes:
H01L27/146; H03F3/50; H04N5/33; H04N5/335; H04N5/341; H04N5/369; H04N5/374; H04N5/378; (IPC1-7): H03F3/50; H01L27/146; H04N5/33; H04N5/335
Domestic Patent References:
| JP61154371A | ||||
| JP9247544A |
Attorney, Agent or Firm:
Sota Asahina
Kei Saki
Kei Saki