RF isolator for isolating voltage sensing and gate drivers

• US 20050271149A1
• Filed: 02/23/2005
• Published: 12/08/2005
• Est. Priority Date: 06/03/2004
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Dupuis, Timothy
• Granted Patent: US 7,460,604 B2
• Time in Patent Office: Days
• 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. 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, comprising:

power transistor gate driver circuitry located on the second side;

voltage sensing circuitry located on the second side;

at least one isolation link 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 RF isolation link further provides voltage isolation between the controller and the power transistor driver circuitry gate and between the controller and the voltage sensing circuitry.

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

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

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

third circuitry on the second side for receiving the driver signal;

fourth circuitry on 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 circuit package of claim 2, further comprising:

an A/D converter on the second side for converting the voltage feedback signal to a digital signal;

a D/A converter on the first side for converting the digital signal to the voltage feedback signal;

4. The circuit package of claim 2, further comprising:

a first transformer on the first side; and

a second transformer on the second side.

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

6. The circuit package 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 circuit package 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 circuit package of claim 7, wherein the memory comprises a one time programable memory.

9. The circuit package of claim 7 wherein the isolation link comprises an RF isolation link.

10. 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, comprising:

power transistor gate driver circuitry located on the second side;

at least one isolation link interconnecting the first and the second sides, the isolation link providing voltage isolation between the first die and the second die, wherein the isolation link further provides voltage isolation between the controller and the power transistor gate driver circuitry.

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

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

second circuitry on the second side for receiving the driver signal; and

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

12. The circuit package of claim 11, further comprising:

a first transformer on the first side; and

a second transformer on the second side.

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

14. The circuit package 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. 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, comprising:

voltage sensing circuitry located on the second side, for sensing the output voltage and generating a voltage feedback signal;

at least one isolation link interconnecting the first side and the second side, the isolation link providing voltage isolation between the first side and the second side, wherein the RF isolation link further provides voltage isolation between the controller and the voltage sensing circuitry.

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

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

second circuitry on the second side for transmitting the voltage feedback signal.

17. The circuit package of claim 16 further including:

an A/D converter on the second side for converting the voltage feedback signal to a digital signal; and

an D/A converter on the first side for converting the digital signal to the voltage feedback signal.

18. The circuit package of claim 16, further comprising:

a first transformer on the first side; and

a second transformer on the second side.

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

20. The circuit package 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 circuit package of claim 20, wherein the memory comprises a one time programable memory.