Claims
- 1. A circuit protecting a current regulating battery charger from a condition of short circuiting or reverse polarity originating at the battery, the charging circuit included consisting of a power transistor in circuit with an emitter-collector load circuit and a base, the protector circuit comprising
- a reference voltage sensing means and the base and emitter junction of a protector transistor forming a path across said load circuit of said power transistor,
- said means having a predetermined reference voltage sensing a voltage drop across said load circuit of said power transistor caused by a condition at the battery,
- said protector transistor having an input to the base of said power transistor, and
- said reference voltage sensing means causing said protector transistor to bias said base of said power transistor to shunt current in excess of said reference voltage.
- 2. A circuit protecting a current regulating battery charger from a voltage drop caused by a condition of short circuiting or reverse polarity originating at the battery, the battery charging circuit included consisting of a power transistor having an emitter-collector load circuit and a base, the protector circuit comprising
- a path across the load circuit of said power transistor,
- said path consisting of a current limiting resistor, a zener diode and the base-emitter junction of a protector transistor,
- said zener diode having a value of a predetermined reference voltage sensing a voltage drop across said load circuit of said power transistor caused by a condition originating at the battery,
- said protector transistor having an input to the base of said power transistor, and
- said protector transistor biasing the base of said power resistor shunting current from the same causing the load circuit thereof to become non-conductive during the time that said voltage drop thereacross exceeds the value of said reference voltage.
Parent Case Info
This application is a continuation-in-part of Ser. No. 933,417 filed Aug. 14, 1978, now abandoned.
US Referenced Citations (8)
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
933417 |
Aug 1978 |
|