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JPS54147876A - Current detector - Google Patents

Current detector

Info

Publication number
JPS54147876A
JPS54147876A JP5554078A JP5554078A JPS54147876A JP S54147876 A JPS54147876 A JP S54147876A JP 5554078 A JP5554078 A JP 5554078A JP 5554078 A JP5554078 A JP 5554078A JP S54147876 A JPS54147876 A JP S54147876A
Authority
JP
Japan
Prior art keywords
voltage
resistance
current
light emitting
protection
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
JP5554078A
Other languages
Japanese (ja)
Inventor
Fumio Fujii
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.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura Electric 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 Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP5554078A priority Critical patent/JPS54147876A/en
Publication of JPS54147876A publication Critical patent/JPS54147876A/en
Pending legal-status Critical Current

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Abstract

PURPOSE: To enable the protection of load and the protection of power source to be performed by series-connecting a parallel circuit of a voltage dividing resistance and a constant voltage element to the series circuit of a light emitting diode and a current limiting resistance so that the detection signal chanes sharply at the abnormality.
CONSTITUTION: When current flows in a current detecting resistance 1, current flows in a light emitting diode 3 by a current limiting resistance 5 and a voltage dividing resistance 12, causing a photo transistor 4 to conduct and voltage to be generated across the resistance 6. When the current flowing in the detecting resistance 1 increases and the voltage across the voltage dividing resistance 12 reaches the conduction voltage of a diode 13 for constant voltage, current begins to flow in the diode 13 and the voltage across the voltage dividing resistance 12 no longer increases, resulting in that the voltage increaments are all applied to the current limiting resistance 5 and light emitting diode 3. Hence, when the current flowing in the detecting resistance 1 exceeds this value, the output voltage sharply increases, thus the protection of the power source or load at the abnormality may be rapidly accomplished.
COPYRIGHT: (C)1979,JPO&Japio
JP5554078A 1978-05-12 1978-05-12 Current detector Pending JPS54147876A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5554078A JPS54147876A (en) 1978-05-12 1978-05-12 Current detector

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5554078A JPS54147876A (en) 1978-05-12 1978-05-12 Current detector

Publications (1)

Publication Number Publication Date
JPS54147876A true JPS54147876A (en) 1979-11-19

Family

ID=13001542

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5554078A Pending JPS54147876A (en) 1978-05-12 1978-05-12 Current detector

Country Status (1)

Country Link
JP (1) JPS54147876A (en)

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