Temperature dependent switching circuit

Details Temperature dependent switching circuit Temperature dependent switching circuit

2007-11-27

2007-11-27

Leja, Ronald W. (Department: 2836)

Electricity: electrical systems and devices

Safety and protection of systems and devices

Circuit interruption by thermal sensing

C327S512000

Reexamination Certificate

active

10903420

ABSTRACT:
A temperature dependent switching circuit comprises a first transistor with a threshold voltage Vth having a negative temperature coefficient. A diode having a forward voltage drop with a negative temperature coefficient coupled with its anode connected to the drain of the first transistor and its cathode connected to the gate of the first transistor. A first resistor is coupled between a power supply terminal and the drain of the first transistor. A low voltage supply is terminal connected to the source of the first transistor. A second resistor is coupled between the gate of the first transistor and the low voltage supply terminal. A switching transistor has its source connected to the low voltage supply terminal and its gate coupled to the drain of the first transistor. The drain of the first transistor provides a voltage with a negative temperature coefficient equal to the sum of the forward voltage drop across the diode and the threshold voltage of the first transistor. As the temperature in the circuit rises to a predetermined temperature the voltage at the gate of the switching transistor drops below the threshold voltage for the switching transistor turning off the current flowing from the drain to the source of the switching transistor.

REFERENCES:
patent: 4877982 (1989-10-01), Walker
patent: 5642252 (1997-06-01), Skatamoto et al.
patent: 6084462 (2000-07-01), Barker
patent: 6088208 (2000-07-01), Yamaguchi
patent: 6342997 (2002-01-01), Khadkikar et al.

Affiliated with

Also associated with

Rating

Temperature dependent switching circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Temperature dependent switching circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Temperature dependent switching circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3829505