COMMUNICATION OVER A VOLTAGE ISOLATION BARRIER

• US 20160065398A1
• Filed: 08/26/2015
• Published: 03/03/2016
• Est. Priority Date: 08/27/2014
• Status: Active Grant

• Current Assignee: Infineon Technologies Americas Corp. (Infineon Technologies AG)
• Original Assignee: International Rectifier Corporation (Infineon Technologies AG)
• Inventors: Candage, Anthony B., Krishnamoorthy, Aswath Krishnan
• Granted Patent: US 9,685,923 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/05554 being square
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• 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: H03F 1/26 Modifications of amplifiers to reduce influence of noise generated by amplifying elements
• CPC Class Codes: H03F 1/3211 in differential amplifiers
• CPC Class Codes: H03F 2200/06 A balun, i.e. balanced to or from unbalanced converter, being present at the input of an amplifier
• CPC Class Codes: H03F 2200/189 the ground, reference or shield potential difference between different chips being controlled
• CPC Class Codes: H03F 2200/453 Controlling being realised by adding a replica circuit or by using one among multiple identical circuits as a replica circuit
• CPC Class Codes: H03F 2203/45562 the IC comprising a cross coupling circuit, e.g. comprising two cross-coupled transistors
• CPC Class Codes: H03F 3/45 Differential amplifiers differential sense amplifiers G11C7/062
• CPC Class Codes: H03F 3/45179 using MOSFET transistors as the active amplifying circuit H03F3/45278 takes precedence
• CPC Class Codes: H03F 3/45632 in differential amplifiers with FET transistors as the active amplifying circuit H03F3/4578 takes precedence
• CPC Class Codes: H03G 3/20 Automatic control H03G3/005 takes precedence; combined with volume compression or expansion H03G7/00
• CPC Class Codes: H03G 3/3052 in bandpass amplifiers (H.F. or I.F.) or in frequency-changers used in a (super)heterodyne receiver H03G3/32, H03G3/34 take precedence
• CPC Class Codes: H04B 15/00 Suppression or limitation of noise or interference by means associated with receiver H04B1/10
• CPC Class Codes: H04L 25/0266 Arrangements for providing Galvanic isolation, e.g. by means of magnetic or capacitive coupling
• CPC Class Codes: H04L 25/0276 Arrangements for coupling common mode signals
• CPC Class Codes: H04L 25/085 Arrangements for reducing interference in line transmission systems, e.g. by differential transmission

Abstract

A transmitter circuit comprises: an input, an encoder circuit, and a transmitter. During operation, the transmitter circuit receives an input signal. The encoder circuit encodes the received input signal into an encoded signal. The encoder circuit produces the encoded signal: i) to indicate changing states of the input signal, and ii) to include a supplemental transient signal with respect to the received input signal. The transmitter transmits the encoded signal from an output of the first circuit over a link to a second circuit such as a receiver circuit. A receiver decodes the encoded signal to reproduce a rendition of the input signal to control remote power supply circuitry. Presence of the supplemental transient signal in the encoded signal indicates to the receiver circuit that the first circuit actively transmits the output signal even though there may not be any change to a current state of the input signal.

Claims

1. An apparatus comprising:

a first circuit comprising;

an input to receive an input signal;

an encoder circuit, the encoder circuit encoding the received input signal into an encoded signal, the encoded signal;

i) indicating changing states of the input signal, and ii) including a supplemental transient signal with respect to the received input signal; and

a transmitter, the transmitter transmitting the encoded signal from an output of the first circuit.

2. The apparatus as in claim 1, wherein presence of the supplemental transient signal in the encoded signal indicates that the first circuit actively transmits the output signal.

3. The apparatus as in claim 2 further comprising:

voltage isolator circuitry disposed between the output of the first circuit and a respective receiver circuit, the voltage isolator circuitry passing AC attributes of the encoded signal to the respective receiver circuit and blocking DC attributes of the encoded signal from being passed to the respective receiver circuit.

4. The apparatus as in claim 3, wherein the transmitter transmits the encoded signal as a differential signal to a second circuit that decodes the differential signal into a reproduced rendition of the input signal.

5. The apparatus as in claim 4, wherein the differential signal includes a first signal and a second signal, the first signal mirroring the second signal;

and

wherein the voltage isolator circuitry includes a first voltage isolator circuit and a second voltage isolator circuit, the transmitter transmitting the first signal through the first voltage isolator circuit to the respective receiver circuit, the transmitter transmitting the second signal to the second voltage isolator circuit to the respective receiver circuit.

6. The apparatus as in claim 1, wherein a frequency of the supplemental transient signal is greater than a frequency of the input signal, the transient signal repeatedly transmitting a notification of a DC state of the encoded input signal to a respective receiver.

7. The apparatus as in claim 1, wherein the transmitter transmits the encoded signal as a differential signal to a second circuit, the second circuit including a decoder circuit that decodes the differential signal to reproduce a rendition of the input signal.

8. The apparatus as in claim 7, wherein the transient signal encoded in the differential signal repeatedly transmits a same DC state of the input signal through voltage isolator circuitry for a duration of time to a respective receiver that decodes the received differential signal.

9. The apparatus as in claim 1 further comprising:

a second circuit;

a communication link extending from the transmitter in the first circuit to a receiver in the second circuit; and

wherein the first circuit is voltage isolated with respect to the second circuit, the second circuit including a high side switch and low side switch, the second circuit controlling states of the high side switch and low side switch based on the encoded signal outputted from the first circuit.

10. The apparatus as in claim 1, wherein the encoded signal transmitted by the transmitter is a differential signal including a first signal and a second signal, the first signal being a multi-state signal, the second signal being a multi-state signal, the first signal inverted with respect to the second signal.

17. The method as in claim 1 further comprising:

transmitting the encoded input signal as a differential signal to a receiver circuit; and

decoding the differential signal to reproduce a rendition of the input signal.

18. The method as in claim 17 further comprising:

including the transient signal in the encoded input signal to repeatedly transmit a same DC state of the input signal through voltage isolator circuitry to a respective receiver that decodes the received differential signal.

11. A method comprising:

receiving an input signal;

encoding the received input signal as an encoded signal, the encoded signal;

i) indicating changing states of the input signal, and ii) including a supplemental transient signal with respect to the received input signal; and

transmitting the encoded signal from an output of the first circuit.

12. The method as in claim 11, wherein presence of the supplemental transient signal in the transmitted encoded signal indicates that a corresponding first circuit actively transmits the encoded input signal.

13. The method as in claim 12, wherein transmitting the encoded signal further comprises:

transmitting the encoded signal through voltage isolator circuitry to a respective receiver circuit, the voltage isolator circuitry passing AC attributes of the transmitted encoded signal to the respective receiver circuit and blocking DC attributes of the encoded signal from being passed to the respective receiver circuit.

14. The method as in claim 13, wherein the transmitter transmits the output signal as a differential signal, the method further comprising:

decoding the differential signal into a replica rendition of the input signal.

15. The method as in claim 14 further comprising:

producing the differential signal to include a first signal mirroring a second signal;

transmitting the first signal through a first voltage isolator circuit to a receiver circuit; and

transmitting the second signal to the second voltage isolator circuit to the respective receiver circuit.

16. The method as in claim 11, wherein a frequency of the supplemental transient signal is greater than a frequency of the input signal, the transient signal repeatedly transmitting a notification of a DC state of the encoded input signal to a respective receiver.

19. The method as in claim 11 further comprising:

transmitting the encoded input signal as a differential signal including a first signal and a second signal, the first signal being a multi-state signal, the second signal being a multi-state signal.

20. The method as in claim 19 further comprising:

producing the first signal to mirror the second signal, the first signal being inverted with respect to the second signal.