JPS5660074A - Variable resistor - Google Patents

Variable resistor

Info

Publication number
JPS5660074A
JPS5660074A JP13550179A JP13550179A JPS5660074A JP S5660074 A JPS5660074 A JP S5660074A JP 13550179 A JP13550179 A JP 13550179A JP 13550179 A JP13550179 A JP 13550179A JP S5660074 A JPS5660074 A JP S5660074A
Authority
JP
Japan
Prior art keywords
contact
potential
switch
impedances
shifted
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP13550179A
Other languages
Japanese (ja)
Inventor
Yoshitoshi Yamauchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP13550179A priority Critical patent/JPS5660074A/en
Publication of JPS5660074A publication Critical patent/JPS5660074A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/12—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof structurally associated with, e.g. formed in or on a common substrate with, one or more electric light sources, e.g. electroluminescent light sources, and electrically or optically coupled thereto
    • H01L31/16—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof structurally associated with, e.g. formed in or on a common substrate with, one or more electric light sources, e.g. electroluminescent light sources, and electrically or optically coupled thereto the semiconductor device sensitive to radiation being controlled by the light source or sources

Landscapes

  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Photo Coupler, Interrupter, Optical-To-Optical Conversion Devices (AREA)
  • Adjustable Resistors (AREA)

Abstract

PURPOSE:To obtain the variable resistor which is not affected by temperature and is insulated at the input and output by negative feeding back the output of the first photodetecting element to an amplifier to which an integrating voltage for irradiating a photo coupler having one light emitting element and first and second photodetecting elements is inputted. CONSTITUTION:When the switching contact (a) of a switch S1 is shifted to a contact (d), a light emitting diode LED irradiates a light, the first phototransistor PT1 is turned on so that the potential at the point (d) becomes 0 volt and the impedances of the phototransistors PT1, PT2 become zero ohm. When the switch S1 is shifted to the contact (c), the integrating circuit of a resistor R1, a capacitor C and an operational amplifier 1 integrates the voltage -V of the power source, the potential at the contact (c) is raised, and the potential when the switch S1 is opened is held. Since the potential at the contact (c) of the operational amplifier 2 is equal to the potential of the contact (d), the impedances of the transistors PT1, PT2 become Vc/I, where the potential of the contact (c) is represented by Vc and the current of the constant-current source 4 is represented by I.
JP13550179A 1979-10-20 1979-10-20 Variable resistor Pending JPS5660074A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13550179A JPS5660074A (en) 1979-10-20 1979-10-20 Variable resistor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13550179A JPS5660074A (en) 1979-10-20 1979-10-20 Variable resistor

Publications (1)

Publication Number Publication Date
JPS5660074A true JPS5660074A (en) 1981-05-23

Family

ID=15153221

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13550179A Pending JPS5660074A (en) 1979-10-20 1979-10-20 Variable resistor

Country Status (1)

Country Link
JP (1) JPS5660074A (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5294089A (en) * 1976-02-02 1977-08-08 Nec Corp Optically coupled semi-conductor element
JPS52141585A (en) * 1976-05-20 1977-11-25 Matsushita Electric Ind Co Ltd Variable resistor

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5294089A (en) * 1976-02-02 1977-08-08 Nec Corp Optically coupled semi-conductor element
JPS52141585A (en) * 1976-05-20 1977-11-25 Matsushita Electric Ind Co Ltd Variable resistor

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