Method and circuit for driving power transistors in a half bridge configuration from control signals referenced to any potential between the line voltage and the line voltage return and integrated circuit incorporating the circuit

• US 5,502,412 A
• Filed: 05/04/1995
• Issued: 03/26/1996
• Est. Priority Date: 05/04/1995
• Status: Expired due to Term

• Current Assignee: International Rectifier Corporation (Infineon Technologies AG)
• Original Assignee: International Rectifier Corporation (Infineon Technologies AG)
• Inventors: Choi, Chongwook C., Tam, David C.
• Primary Examiner(s): Heyman, John S.
• Application Number:
  US08/433,841
• Time in Patent Office: 327 Days
• Field of Search: 327/333, 327/112, 327/427
• US Class Current: 327/333
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H02M 7/538 in a push-pull configuration H02M7/5375 takes precedence ; with oscillating arrangements H02M7/53832, H02M7/53846
• CPC Class Codes: H03K 17/063 in field-effect transistor switches
• CPC Class Codes: H03K 17/6871 the output circuit comprising more than one controlled field-effect transistor

Abstract

A circuit for driving power transistors in a half bridge configuration from a control signal referenced to any potential between the line voltage for the power transistors and the line voltage return. The circuit includes an input circuit receiving a control signal referenced to any potential between the line voltage and the line voltage return, the input circuit being supplied with two voltage levels floating with respect to a common voltage level, a first level shifting circuit receiving an output of the input circuit which shifts the level of the output of the input circuit so that it is referenced to the common voltage level, a low side driver circuit for the power transistor in the half bridge configuration which functions as the low side power transistor, the low side driver circuit receiving the output referenced to the common voltage level, a second level shifting circuit which shifts the level of the output from the first level shifting circuit to produce a signal referenced to a second higher voltage level than said common level, and a driver circuit receiving the signal referenced to the second higher voltage level for driving the power transistor comprising the high side power transistor in the half bridge configuration. The circuit can be incorporated in an integrated circuit comprising a single chip, i.e., a silicon chip.

Claims

1. A method for driving power transistors in a half bridge configuration from a control signal referenced to any potential between the line voltage for the power transistors and the line voltage return, comprising:

providing a control signal referenced to any potential between the line voltage and the line voltage return to an input circuit;

providing said input circuit with two voltage levels floating with respect to a common voltage level;

providing an output of said input circuit to a first level shifting circuit which shifts the level of the output of the input circuit so that it is referenced to the common voltage level;

providing said output referenced to the common voltage level to a low side driver circuit for the power transistor in said half bridge configuration which functions as a low side power transistor;

providing said output referenced to said common voltage level also to a second level shifting circuit which shifts the level of said output from said first level shifting circuit to produce a signal referenced to a second higher voltage level than said common level; and

providing the signal referenced to said second higher voltage level to a high side driver circuit for driving the power transistor comprising the high side power transistor in said half bridge configuration.

2. The method recited in claim 1, wherein said two voltage levels floating with respect to a common voltage level are selected depending on the level of the line voltage and the return.

3. A circuit for driving power transistors in a half bridge configuration from a control signal referenced to any potential between the line voltage for the power transistors and the line voltage return, comprising:

an input circuit receiving a control signal referenced to any potential between the line voltage and the line voltage return, said input circuit being supplied with two voltage levels floating with respect to a common voltage level;

a first level shifting circuit receiving an output of said input circuit which shifts the level of the output of the input circuit so that it is referenced to the common voltage level;

a low side driver circuit for the power transistor in said half bridge configuration which functions as the low side power transistor, said low side driver circuit receiving said output referenced to the common voltage level;

a second level shifting circuit which shifts the level of said output from said first level shifting circuit to produce a signal referenced to a second higher voltage level than said common level; and

a driver circuit receiving the signal referenced to said second higher voltage level for driving the power transistor comprising the high side power transistor in said half bridge configuration.

4. The circuit recited in claim 3, further comprising a reverse biased diode across said first level shifting circuit and a reverse biased diode across said second level shifting circuit, each of said diodes being able to withstand at least a potential of twice the line voltage.

5. The circuit recited in claim 3, wherein said two voltage levels floating with respect to a common voltage level are selected depending on the level of the line voltage and the return.

6. A method of integrating on a single integrated circuit chip a circuit for driving power transistors in a half bridge configuration from a control signal referenced to any potential between the line voltage for the power transistors and the line voltage return, comprising:

providing a control signal referenced to any potential between the line voltage and the line voltage return to an input circuit;

providing said input circuit with two voltage levels floating with respect to a common voltage level;

providing an output of said input circuit to a first level shifting circuit which shifts the level of the output of the input circuit so that it is referenced to the common voltage level;

providing said output referenced to the common voltage level to a low side driver circuit for the power transistor in said half bridge configuration which functions as a low side power transistor;

providing said output referenced to said common voltage level also to a second level shifting circuit which shifts the level of said output from said first level shifting circuit to produce a signal referenced to a second higher voltage level than said common level; and

providing the signal referenced to said second higher voltage level to a high side driver circuit for driving the power transistor comprising the high side power transistor in said half bridge configuration.

7. The method recited in claim 6, wherein said two voltage levels floating with respect to a common voltage level are selected depending on the level of the line voltage and the return.

8. A circuit integrated on a single integrated circuit chip for driving power transistors in a half bridge configuration from a control signal referenced to any potential between the line voltage for the power transistors and the line voltage return, comprising:

an input circuit receiving a control signal referenced to any potential between the line voltage and the line voltage return, said input circuit being supplied with two voltage levels floating with respect to a common voltage level;

a first level shifting circuit receiving an output of said input circuit which shifts the level of the output of the input circuit so that it is referenced to the common voltage level;

a low side driver circuit for the power transistor in said half bridge configuration which functions as the low side power transistor, said low side driver circuit receiving said output referenced to the common voltage level;

a second level shifting circuit which shifts the level of said output from said first level shifting circuit to produce a signal referenced to a second higher voltage level than said common level; and

a driver circuit receiving the signal referenced to said second higher voltage level for driving the power transistor comprising the high side power transistor in said half bridge configuration.

9. The circuit recited in claim 8, further comprising a reverse biased diode across said first level shifting circuit and a reverse biased diode across said second level shifting circuit, each of said diodes being able to withstand at least a potential of twice the line voltage.

10. The circuit recited in claim 8, wherein said two voltage levels floating with respect to a common voltage level are selected depending on the level of the line voltage and the return.