Electronic device including parts forming a voltage transformer

• US 6,992,875 B2
• Filed: 10/09/2002
• Issued: 01/31/2006
• Est. Priority Date: 10/09/2001
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schenk, Joachim, Breunig, Volker
• Primary Examiner(s): Sircus, Brian
• Assistant Examiner(s): Nguyen, Danny
• Application Number:
  US10/267,248
• Publication Number:
  US 20030085695A1
• Time in Patent Office: 1,210 Days
• Field of Search: 361/155, 361/156, 361/160, 361/166, 361/181, 361/183, 361/187, 361/190, 361/191, 361/18, 323/282, 323/283, 323/284, 363/13, 363/15, 363/34
• US Class Current: 361/160
• CPC Class Codes: H02M 1/0006 Arrangements for supplying an adequate voltage to the control circuit of converters
• CPC Class Codes: H02M 3/155 using semiconductor devices only
• CPC Class Codes: H02M 3/1555 for the generation of a regulated current to a load whose impedance is substantially inductive

Abstract

An electronic device, in particular a control unit including an electromagnetic actuator, whose coil is at the same time part of a voltage transformer. The coil is connected through a switch to an operating voltage potential or to a reference potential. A capacitor is also provided. The coil, the capacitor and the switch constitute a voltage transformer.

Claims

1. An electronic device comprising:

a switch;

an electromagnetic actuator including a coil that is connectable through the switch to one of an operating voltage potential and a reference potential;

a capacitor;

wherein the coil, the capacitor and the switch are configured to form a voltage transformer;

wherein the switch includes a circuit breaker that connects the coil to one of the operating voltage potential and the reference potential, and the switch includes a diode through which the capacitor is charged through the coil when the circuit breaker is open;

wherein a switching process is cyclical with a predefined mark-to-space ratio being set; and

wherein the predefined mark-to-space ratio is less than a predefined maximum value, and the predefined maximum value is chosen to avoid activation of the electromagnetic actuator and such that a current in the coil is less than a making current of the electromagnetic actuator at which the electromagnetic actuator is activated.

2. The electronic device of claim 1, wherein the electronic device includes a control unit.

3. The electronic device of claim 1, wherein the electromagnetic actuator includes a relay.

4. The electronic device of claim 1, wherein the voltage transformer includes a step-down transformer.

5. The electronic device of claim 1, wherein the voltage transformer includes a step-up transformer.

6. The electronic device of claim 1, wherein the voltage transformer includes an inverting transformer.

7. The electronic device of claim 1, wherein the circuit breaker includes a controlled switch.

8. The electronic device of claim 7, wherein the controlled switch includes a transistor.

9. The electronic device of claim 1, wherein the predefined mark-to-space ratio one of assumes and exceeds a predefined minimum value, the predefined minimum value is chosen such that a mean current in the coil is at least equal to a holding current of the electromagnetic actuator, which is a minimum necessary to hold a switched state of the electromagnetic actuator after it is activated.

10. The electronic device of claim 1, wherein a voltage generated by the voltage transformer supplies a processor of the electronic device.