JPS54156154A - Transistor protective circuit for power unit - Google Patents

Transistor protective circuit for power unit

Info

Publication number
JPS54156154A
JPS54156154A JP6509478A JP6509478A JPS54156154A JP S54156154 A JPS54156154 A JP S54156154A JP 6509478 A JP6509478 A JP 6509478A JP 6509478 A JP6509478 A JP 6509478A JP S54156154 A JPS54156154 A JP S54156154A
Authority
JP
Japan
Prior art keywords
voltage
control transistor
transistor
main control
input terminal
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
JP6509478A
Other languages
Japanese (ja)
Inventor
Mitsuo Nakamura
Hiroshi Shimamori
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP6509478A priority Critical patent/JPS54156154A/en
Publication of JPS54156154A publication Critical patent/JPS54156154A/en
Pending legal-status Critical Current

Links

Landscapes

  • Continuous-Control Power Sources That Use Transistors (AREA)

Abstract

PURPOSE: To protect the main control transistor by making the base current of the transistor cut off with the output of the detection circuit when the voltage exceeds the specified level between the emitter and the collector of the transistor while by bringing the control transistor thus cut off out of action when the power unit is started.
CONSTITUTION: In a circuit designed to obtain a more stable output voltage Vo than the input voltage Vi with a main control transistor Q1, the input voltage Vi is applied on the positive input terminal of an arithmetic applifier IC1 through voltage dividing resistances R1 and R2 while the output voltage Vo is applied on the negative input terminal so that a negative input terminal potential resis in the normal operation. The input voltage Vi resis, causing the voltage to exceed the specified level between the emitter and collector of the main control transistor Q1. Then, the positive input terminal potential gains higher than the negative input terminal potential of the arithmetic amplifier, ultimately elevating the output of the arithmetic amplifier to a high level. This turns the transistor Q3 on thereby allowing the base potential of the main control transistor Q1 to reach the ground potential. In this manner, the main control transistor can be cut off.
COPYRIGHT: (C)1979,JPO&Japio
JP6509478A 1978-05-31 1978-05-31 Transistor protective circuit for power unit Pending JPS54156154A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6509478A JPS54156154A (en) 1978-05-31 1978-05-31 Transistor protective circuit for power unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6509478A JPS54156154A (en) 1978-05-31 1978-05-31 Transistor protective circuit for power unit

Publications (1)

Publication Number Publication Date
JPS54156154A true JPS54156154A (en) 1979-12-08

Family

ID=13276982

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6509478A Pending JPS54156154A (en) 1978-05-31 1978-05-31 Transistor protective circuit for power unit

Country Status (1)

Country Link
JP (1) JPS54156154A (en)

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