Title:
光リーク電流補償回路およびそれを用いる光信号用回路
Document Type and Number:
Japanese Patent JP4040455
Kind Code:
B2
Abstract:
When a current mirror circuit is composed of transistors that inevitably form a parasitic photodiode between an epitaxial layer and a substrate layer because of structure of an integrated circuit, a photocurrent increases in proportional to an area of the epitaxial layer. Thus, the area of the epitaxial layer is adjusted in accordance with a current ratio of the current mirror, so as to allow the photocurrent to affect equally on both input and output sides of the current mirror circuit, i.e., so as to cancel the photocurrent. With this, in a current mirror circuit provided in an integrated circuit, it is possible to eliminate the influence of the photocurrent, without considerably increasing an element area or taking special measures to shield light.
Inventors:
Takahiro Inoue
Seiichi Yokokawa
Ryosuke Kawashima
Seiichi Yokokawa
Ryosuke Kawashima
Application Number:
JP2002381693A
Publication Date:
January 30, 2008
Filing Date:
December 27, 2002
Export Citation:
Assignee:
Sharp Corporation
International Classes:
H01L27/14; H03F3/08; G05F3/26; H01J40/14; H01L21/8222; H01L23/58; H01L27/06; H01L27/082; H01L31/09
Domestic Patent References:
| JP3292775A | ||||
| JP1217959A | ||||
| JP7022864A |
Attorney, Agent or Firm:
Kenzo Hara
Ryuichi Kijima
Ichiro Kaneko
Ryuichi Kijima
Ichiro Kaneko