Back to results
US 6,028,470 AGranted
Integrated circuit for current control of a power transistor
AssigneeRobert Bosch GmbH
InventorsHartmut Michel, Christian Pluntke
Life of this patent
Estimating the term…
Abstract
An integrated circuit comprising a power transistor and a circuit arrangement. The circuit arrangement is thermally coupled to the power transistor and operates in a temperature-dependent fashion. The integrated circuit includes a pnp or npn transistor with a temperature dependent resistor coupled between the base and emitter of the transistor. The off-state current of the transistor changes as a function of temperature and initiates a change in a base current of the power transistor.
Claims14
An integrated circuit comprising:
- a base terminal;
- a power transistor having a base and a base current;
- and
- a circuit arrangement coupled to the power transistor and operating in a temperature-dependent fashion, the circuit arrangement including:
- a first pnp transistor having a base, a collector and an emitter, the first pnp transistor having an off-state current changing as a function of temperature and initiating a change in the base current of the power transistor,
- a temperature-dependent resistor coupled between the base and the emitter of the first pnp transistor, the temperature-dependent resistor having a positive temperature coefficient, and
- a second transistor having a collector and an emitter through which the base current of the power transistor flows, the collector of the second transistor being coupled to the base terminal of the integrated circuit and to the emitter of the first pnp transistor, the emitter of the second transistor being coupled to the base of the power transistor.
4 more elements
An integrated circuit comprising:
- a base terminal;
- a power transistor having a base and a base current;
- a circuit arrangement coupled to the power transistor and operating in a temperature-dependent fashion, the circuit arrangement including:
- a first npn transistor having a base, a collector and an emitter, the first npn transistor having an off-state current, the off-state current changing as a function of temperature and initiating a change in the base current of the power transistor,
- a temperature-dependent resistor coupled between the base and the emitter of the first npn transistor, the temperature-dependent resistor having a positive temperature coefficient, and
- a second transistor having a collector and an emitter through which the base current of the power transistor flows, the collector of the second transistor being coupled to the base terminal of the integrated circuit and the collector of the first npn transistor, the emitter of the second transistor being coupled to the base of the power transistor.
3 more elements
Dependencies are inferred from the claim text.