RF isolator for isolating voltage sensing and gate drivers

• US 7,460,604 B2
• Filed: 02/23/2005
• Issued: 12/02/2008
• Est. Priority Date: 06/03/2004
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Dupuis, Timothy
• Primary Examiner(s): Ahn; Sam K
• Application Number:
  US11/064,413
• Publication Number:
  US 20050271149A1
• Time in Patent Office: 1,378 Days
• Field of Search: 375/257, 375/258, 375/265, 327/177, 327/304, 327/382, 327/565, 438/197, 438/270, 438/288, 438/335
• US Class Current: 375/258
• CPC Class Codes: H01L 2224/05554 being square
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48095 Kinked
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48464 the other connecting portion not on the bonding area also being a ball bond, i.e. ball-to-ball
• CPC Class Codes: H01L 2224/4847 the connecting portion on the bonding area of the semiconductor or solid-state body being a wedge bond
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 2224/49176 Wire connectors having the same loop shape and height
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• 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 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01014 Silicon [Si]
• CPC Class Codes: H01L 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/01023 Vanadium [V]
• CPC Class Codes: H01L 2924/01027 Cobalt [Co]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/1204 : Optical Diode
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/13055 : Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/13091 : Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19042 : being an inductor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H01L 2924/30105 : Capacitance
• CPC Class Codes: H01L 2924/30107 : Inductance
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H02M 3/33523 : with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H04B 3/30 : Reducing interference caused by unbalanced currents in a normally balanced line
• CPC Class Codes: H04L 25/0268 : with modulation and subsequent demodulation

Abstract

A circuit package for providing isolation between a controller on a first side of a switched power supply and a second side of the switched power supply. An isolation link provides voltage isolation between the first and second sides and includes on the first sides circuitry for transmitting a driver signal received from the controller and circuitry for receiving a voltage feedback signal responsive to a sensed output voltage on the second side. The second side includes circuitry for receiving the driver signal and also circuitry for transmitting the voltage feedback signal. A driver located on the second side is responsive to the received driver signal. The second side further includes circuitry for sensing the output voltage and generating the voltage feedback signal. The isolation link additionally provides voltage isolation between the controller and the driver circuit and between the controller and the sensed output voltage.

Claims

1. An apparatus, comprising:

a single integrated circuit package for providing isolation between a controller on a first side of a switched power supply and a second side of the switched power supply;

power transistor gate driver circuitry located within the single integrated circuit for driving power transistors on the second side of the switched power supply;

voltage sensing circuitry located within the single integrated circuit for sensing an output voltage of the switched power supply on the second side;

at least one isolation link located within the single integrated circuit interconnecting the first and the second side of the switched power supply, the isolation link providing voltage isolation between the first side and the second side of the switched power supply, wherein the isolation link further provides voltage isolation between the controller and the power transistor driver circuitry gate and between the first side of the switched power supply and the voltage sensing circuitry.

2. The apparatus of claim 1, wherein the isolation link further comprises:

first circuitry associated with the first side for transmitting a driver signal received from the controller;

second circuitry associated with the first side for receiving the voltage feedback signal responsive to a sensed output voltage on the second side;

third circuitry associated with the second side for receiving the driver signal;

fourth circuitry associated with the second side for transmitting the voltage feedback signal; and

wherein the power transistor gate driver circuitry is responsive to the driver signal.

3. The apparatus of claim 2, further comprising:

an analog to digital (A/D) converter associated with the second side for converting the voltage feedback signal to a digital signal;

a digital to analog (D/A) converter associated with the first side for converting the digital signal to the voltage feedback signal;

4. The apparatus of claim 2, further comprising:

a first transformer associated with the first side; and

a second transformer associated with the second side.

5. The apparatus of claim 4, wherein the second transformer comprises a center tap transformer.

6. The apparatus of claim 2, further comprising a level shifter between the power transistor gate driver circuitry and the third circuit for increasing a voltage level of the received driver signal.

7. The apparatus of claim 2, further comprising:

an operational amplifier having a first input connected to detect the output voltage and a second input connected to a reference voltage;

a bandgap generator for generating the reference voltage responsive to a digital trim signal; and

a memory for storing the digital trim signal.

8. The apparatus of claim 7, wherein the memory comprises a one time programmable memory.

9. The apparatus of claim 7 wherein the isolation link comprises an radio frequency RF isolation link.

10. An apparatus, comprising:

a single integrated circuit package for providing isolation between a controller on a first side of a switched power supply and a second side of the switched power supply;

power transistor gate driver circuitry located within the single integrated circuit for driving power transistors on the second side of the power supply;

at least one isolation link located within the single integrated circuit for interconnecting the first and the second sides, the isolation link providing voltage isolation between the first side and the second side of the switched power supply, wherein the isolation link further provides voltage isolation between the controller and the power transistor gate driver circuitry.

11. The apparatus package of claim 10, wherein the isolation link further includes:

first circuitry associated with the first side for transmitting a driver signal received from the controller;

second circuitry associated with the second side for receiving the driver signal; and

wherein the power transistor gate driver circuitry is responsive to the driver signal.

12. The apparatus of claim 11, further comprising:

a first transformer associated with the first side; and

a second transformer associated with the second side.

13. The apparatus of claim 12, wherein the second transformer comprises a center tap transformer.

14. The apparatus of claim 11, further comprising a level shifter between the power transistor gate driver circuitry and the second circuit for increasing a voltage level of the received driver signal.

15. An apparatus, comprising:

a single integrated circuit package for providing isolation between a first side of a switched power supply and a second side of the switched power supply,

voltage sensing circuitry located within the single integrated circuit package for sensing the output voltage of the switched power supply on the second side and generating a voltage feedback signal;

at least one isolation link located within the single integrated circuit interconnecting the first side and the second side, the isolation link providing voltage isolation between the first side and the second side, wherein the isolation link further provides voltage isolation between a controller in the first side of the switched power supply and the voltage sensing circuitry.

16. The apparatus of claim 15, wherein the isolation link further includes:

first circuitry associated with the first side for receiving the voltage feedback signal responsive to a sensed output voltage on the second side;

second circuitry associated with the second side for transmitting the voltage feedback signal.

17. The apparatus of claim 16 further including:

an analog to digital (A/D) converter associated with the second side for converting the voltage feedback signal to a digital signal; and

an digital to analog (D/A) converter associated with the first side for converting the digital signal to the voltage feedback signal.

18. The apparatus of claim 16, further comprising:

a first transformer associated with the first side; and

a second transformer associated with the second side.

19. The apparatus of claim 18, wherein the second transformer comprises a center tap transformer.

20. The apparatus of claim 16, further comprising:

an operational amplifier having a first input connected to detect the output voltage and a second input connected to a reference voltage;

a bandgap generator for generating the reference voltage responsive to a digital trim signal; and

a memory for storing the digital trim signal.

21. The apparatus of claim 20, wherein the memory comprises a one time programmable memory.