System, Drivers for Switches and Methods for Synchronizing Measurements of Analog-to-Digital Converters

• US 20130088264A1
• Filed: 10/10/2011
• Published: 04/11/2013
• Est. Priority Date: 10/10/2011
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Barrenscheen, Jens, Beaurenaut, Laurent
• Granted Patent: US 8,947,126 B2
• Time in Patent Office: Days
• US Class Current: 327/108
• CPC Class Codes: H03K 17/162 without feedback from the output circuit to the control circuit
• CPC Class Codes: H03K 17/689 with galvanic isolation between the control circuit and the output circuit H03K17/78 takes precedence
• CPC Class Codes: H03K 2217/0027 Measuring means of, e.g. currents through or voltages across the switch
• CPC Class Codes: H03K 2217/0063 High side switches, i.e. the higher potential [DC] or life wire [AC] being directly connected to the switch and not via the load
• CPC Class Codes: H03K 2217/0072 Low side switches, i.e. the lower potential [DC] or neutral wire [AC] being directly connected to the switch and not via the load

Abstract

A driver for a switch includes a primary side having a trigger input and a secondary side comprising an analog-to-digital converter (ADC). The primary side and the secondary side are separated by a galvanic isolation barrier and communicate via a communication circuit. The primary side is configured to receive a trigger signal at the trigger input and forward the trigger signal to the ADC of the secondary side of the driver via the communication circuit. The ADC is configured to start a measurement upon receiving the trigger signal.

Claims

1. A driver for a switch, the driver comprising:

a primary side having a trigger input;

a secondary side comprising an analog-to-digital converter (ADC);

a galvanic isolation barrier, wherein the primary side and the secondary side are separated by the galvanic isolation barrier;

a communication circuit, wherein the primary side and the secondary side communicate via the communication circuit;

wherein the primary side is configured to receive a trigger signal at the trigger input and forward the trigger signal to the ADC of the secondary side of the driver via the communication circuit; and

wherein the ADC is configured to start a measurement upon receiving the trigger signal.

2. The driver of claim 1, wherein the communication circuit comprises an inductive coupler.

3. The driver of claim 1, wherein the communication circuit comprises a coreless transformer.

4. The driver of claim 1, wherein the primary side and the secondary side are configured to transfer configuration data and trigger requests and, as long as the trigger signal is enabled, only trigger requests are transmitted via the communication circuit.

5. A method for synchronizing a measurement of an analog-to-digital converter (ADC) in a driver comprising a primary side having a trigger input and a secondary side comprising the ADC, wherein the primary side and the secondary side are separated by a galvanic isolation barrier and communicate via a communication circuit, the method comprising:

receiving a trigger signal at the trigger input of the primary side of the driver; and

forwarding the trigger signal to the ADC of the secondary side of the driver via the communication circuit to cause the ADC to start a measurement.

6. The method of claim 5, wherein the communication circuit comprises an inductive coupler.

7. The method of claim 5, wherein the communication circuit comprises a coreless transformer.

8. The method of claim 5, wherein the primary side and the secondary side are configured to transfer configuration data and trigger requests and, as long as the trigger signal is enabled, only trigger requests are transmitted via the communication circuit.

9. The method of claim 5, wherein the trigger signal is also received by a further driver comprising a further primary side having a further trigger input and a further secondary side comprising a further ADC, wherein the further primary side and the further secondary side are separated by a further galvanic isolation barrier and communicate via a further communication circuit, the method further comprising:

receiving the trigger signal at the further trigger input of the further primary side of the further driver; and

forwarding the further trigger signal to the further ADC of the further secondary side of the further driver via the further communication circuit to cause the further ADC to start a further measurement essentially synchronously with the measurement of the ADC.

10. A driver for a switch, the driver comprising:

a primary side connected to a control unit; and

a secondary side connected to a switch and comprising an analog-to-digital converter (ADC) for measuring a value related to the switch, wherein the primary side and the secondary side are separated by a galvanic isolation barrier and communicate via a communication circuit;

wherein the primary side is configured to receive a pulse width modulation (PWM) control signal from the control unit and to transmit, via the communication circuit, the received PWM control signal to the secondary side to control an output of the driver to the switch; and

wherein the secondary side is configured to synchronize the measurement of the ADC with the PWM control signal.

11. The driver of claim 10, wherein the ADC is a successive approximation ADC.

12. The driver of claim 10, wherein the communication circuit comprises a coreless transformer.

13. The driver of claim 10, wherein the secondary side further comprises an edge detector for detecting a falling edge or a rising edge of the PWM control signal.

14. The driver of claim 10, wherein either a falling edge or a rising edge of the PWM control signal initiates a start of the measurement of the ADC.

15. The driver of claim 10, wherein either a falling edge or a rising edge of the PWM control signal initiates a start of the measurement of the ADC after a configurable delay.

16. The driver of claim 10, wherein the primary side further comprises a trigger circuit configured to receive an external trigger, wherein the measurement of the ADC is triggered by a falling or rising edge of the PWM control signal only when the external trigger is enabled.

17. The driver of claim 16, wherein the trigger circuit comprises an input pin, a timer, or a register configured to be written by a microcontroller.

18. A system comprising:

a first driver comprising a first primary side connected to a control unit and a first secondary side connected to a first switch and comprising a first analog-to-digital converter (ADC) for measuring a value related to the first switch, wherein the first primary side and the first secondary side are separated by a first galvanic isolation barrier and communicate via a first communication circuit, wherein the first primary side is configured to receive a first pulse width modulation (PWM) control signal from the control unit and to transmit, via the first communication circuit, the received first PWM control signal to the first secondary side to control an output of the first driver to the first switch, wherein an edge of the first PWM control signal initiates the start of a measurement of the first ADC after a configurable first delay; and

a second driver comprising a second primary side connected to the control unit and a second secondary side connected to a second switch and comprising a second ADC for measuring a value related to the second switch, wherein the second primary side and the second secondary side are separated by a second galvanic isolation barrier and communicate via a second communication circuit, wherein the second primary side is configured to receive a second PWM control signal from the control unit and to transmit, via the second communication circuit, the received second PWM control signal to the second secondary side to control an output of the second driver to the second switch, wherein an edge of the second PWM control signal initiates the start of a measurement of the second ADC after a configurable second delay.

19. The system of claim 18, wherein the first delay and the second delay are configured to synchronize the measurements of the first ADC and the second ADC.

20. The system of claim 19, wherein the first switch comprises a high-side switch of a half bridge and the second switch comprises a low-side switch of the half-bridge.

21. The system of claim 20, wherein the first delay and the second delay are calculated based on a dead time in the first and second PWM control signals.

22. The system of claim 21, wherein the first delay and the second delay differ by the dead time.

23. A method for synchronizing a measurement of an analog-to-digital converter (ADC) in a driver comprising a primary side connected to a control unit and a secondary side connected to a switch and comprising the ADC configured to measure a value related to the switch, wherein the primary side and the secondary side are separated by a galvanic isolation barrier and communicate via a communication circuit, wherein the method comprises:

receiving, by the primary side, a pulse width modulation (PWM) control signal transmitted by the control unit;

transmitting, by the primary side, via the communication circuit, the received PWM control signal to the secondary side to control an output of the driver to the switch; and

synchronizing a measurement of the ADC with the PWM control signal utilizing edges of the PWM control signal for triggering measurement of the ADC.

24. The method of claim 23, wherein the communication circuit comprises a coreless transformer.

25. The method of claim 23, wherein either a falling edge or a rising edge of the PWM control signal initiates a start of the measurement of the ADC, the measurement being accomplished before the falling/rising edge of the PWM control signal results in a change of a driving signal for the switch due to a delay of the driver.

26. The method of claim 23, wherein either a falling edge or a rising edge of the PWM control signal initiates the start of the measurement of the ADC after a configurable delay.

27. The method of claim 23, further comprising receiving an external trigger signal, wherein the measurement of the ADC is triggered by a falling or rising edge of the PWM signal only when the external trigger signal is enabled.

28. The method of claim 23, further comprising transmitting, by the control unit, the PWM control signal to the primary side of the driver.