JPS54156154A - Transistor protective circuit for power unit - Google Patents
Transistor protective circuit for power unitInfo
- 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
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
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) |
-
1978
- 1978-05-31 JP JP6509478A patent/JPS54156154A/en active Pending
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