Signal generator and control unit for sensing signals of signal generator

• US 6,346,781 B1
• Filed: 06/04/2001
• Issued: 02/12/2002
• Est. Priority Date: 09/22/1999
• Status: Expired due to Fees

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Electronics Company Incorporated (Lutron Electronics)
• Inventors: Carmen, Lawrence R. Jr., Mosebrook, Donald R.
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): VO, TUYET THI
• Application Number:
  US09/873,749
• Publication Number:
  US 20020011808A1
• Time in Patent Office: 253 Days
• Field of Search: 315/294, 315/297, 315/292, 315/320, 315/291, 315/307, 315/322, 315/315, 315/149, 315/DIG.4
• US Class Current: 315/294
• CPC Class Codes: H05B 47/185 via power line carrier transmission

Abstract

A signal generating circuit coupled to an AC supply, the circuit comprising at least one first switch device coupled to the AC supply, at least one triggerable switch device coupled to the first switch device, operation of the first switch device causing said triggerable switch device to trigger in response to the AC supply at a predetermined voltage, thereby providing at least a portion of a waveform of the AC supply as a control signal and wherein the control signal terminates within a predetermined period of time after operation of the first switch device terminates. A circuit for detecting and responding to the signals generated by the signal generator is also disclosed.

Claims

1. A signal generator comprising:

a plurality of switches adapted to be coupled to an alternating current source, the source having an alternating current source signal waveform;

each switch in series with a voltage threshold triggered switch device comprising at least one of a zener diode, diac, triac and silicon controlled rectifier;

the signal generator producing an output when one of the plurality of switches is actuated, the output representing a uniquely coded signal dependent on which of the plurality of switches is actuated, the output comprising a selected portion of the alternating current source signal waveform for a cycle of the alternating current source signal waveform;

wherein the output comprises at least one of;

a half cycle of the output having zero crossings spaced closer together than the alternating current source signal waveform;

two half cycles of the output with one half cycle having zero crossings spaced closer together than the alternating current source signal waveform; and

two half cycles of the output wherein both half cycles have zero crossings spaced closer together than the alternating current source signal waveform.

2. A signal encoding and detector circuit comprising:

a signal encoding circuit adapted to be coupled to an AC source having an AC source waveform, the signal encoding circuit encoding a cycle of the AC source waveform as an encoded signal by providing at least one of;

at least one half cycle of the encoded signal having zero crossings spaced closer together than the AC source waveform;

two half cycles of the encoded signal with one half cycle having zero crossings spaced closer together than the AC source waveform;

two half cycles of the encoded signal wherein both half cycles have zero crossings spaced closer together than the AC source waveform; and

at least one half cycle of the encoded signal having a delayed turn-on portion whereby the delayed turn-on portion comprises an edge turn-on portion;

further comprising;

a sense circuit,

a control circuit coupled to the sense circuit,

the control circuit producing a selected control signal when the sense circuit receives said encoded signal.

3. The signal encoding and detector circuit of claim 2, wherein the control circuit obtains samples from the sense circuit at a plurality of predefined times in each half cycle of the encoded signal in order to determine a shape of the AC signal.

4. The signal encoding and detector circuit of claim 2, wherein the sense circuit senses a duration and polarity of said encoded signal.

5. A signal generator comprising:

a plurality of switches adapted to be coupled to an alternating current source, the source having an alternating current source signal waveform;

each switch in series with a voltage threshold triggered switch device comprising at least one of a zener diode, diac, triac and silicon controlled rectifier;

the signal generator producing an output when one of the plurality of switches is actuated, the output representing a uniquely coded signal dependent on which of the plurality of switches is actuated, the output comprising a selected portion of the alternating current source signal waveform for a cycle of the alternating current source signal waveform.

6. The signal generator of claim 5, wherein the signal generator comprises two and only two conductors for connection to a sense circuit, the sense circuit coupled to the AC source.

7. The signal generator of claim 5, wherein at least one switch comprises a tactile switch.

8. The signal generator of claim 5, wherein at least one switch comprises a semiconductor switch.

9. The signal generator of claim 5, wherein at least one switch comprises a momentary contact switch.

10. The signal generator of claim 5, wherein the output has a region having a substantially constant current, the substantially constant current being approximately a zero current.

11. The signal generator of claim 5, wherein the voltage threshold triggered switch device comprises a Zener diode.

12. The signal generator of claim 5, wherein the output comprises at least a portion of one half cycle of the alternating current source signal waveform, the portion having a delayed turn-on caused by said voltage threshold triggered switch device, whereby the delayed turn-on comprises an edge turn-on portion.

13. The signal generator of claim 12 wherein the voltage threshold triggered switch device comprises one of a Zener diode, diac, triac and silicon controlled rectifier.

14. A signal generating circuit comprising:

a plurality of first switch devices adapted to be coupled to an AC supply, the AC supply having an AC supply waveform;

at least one triggered switch device coupled to at least one of the first switch devices, the at least one triggered switch device comprising at least one of a zener diode, a diac, a triac and a silicon controlled rectifier;

operation of at least one of the first switch devices causing said triggered switch device to trigger in response to the AC supply at a predetermined voltage, thereby providing at least a portion of a waveform of the AC supply as a control signal and wherein the control signal terminates within a predetermined period of time after operation of the first switch device terminates, and further wherein each of the plurality of switches provides a unique control signal comprising at least a half cycle of the AC supply waveform that is different from the control signal provided by each other of said plurality of switches.

15. The signal generating circuit of claim 14, wherein the predetermined period of time is one ine cycle of the AC supply.

16. The signal generating circuit of claim 14, wherein the triggered switch device comprises a Zener diode.

17. The signal generating circuit of claim 16, wherein the Zener diode is coupled in series with at least one of the first switch devices.

18. The signal generating circuit of claim 16 further comprising a diode coupled in series with the Zener diode and at least one of the first switch devices.

19. The signal generating circuit of claim 16, further comprising a further Zener diode, the further Zener diode being polarized opposite the Zener diode.

20. The signal generating circuit of claim 14, wherein the triggered switch device comprises a semiconductor switch having a control electrode, the control electrode being coupled to a trigger circuit.

21. The signal generating circuit of claim 20, wherein the trigger circuit comprises Zener diode.

22. The signal generating circuit of claim 20, wherein at least one of the first switch devices is coupled in series with the semiconductor switch.

23. The signal generating circuit of claim 20 wherein the semiconductor switch comprises a silicon controlled rectifier.

24. The signal generating circuit of claim 20, wherein at least one of the first switch devices is coupled in series with the trigger circuit.

25. The signal generating circuit of claim 24, wherein the trigger circuit comprises a Zener diode.

26. The signal generating circuit of claim 20, wherein the trigger circuit comprises a time constant circuit coupled in series with at least one of the first switch devices.

27. The signal generating circuit of claim 26, wherein the time constant circuit is coupled to the control electrode to trigger the semiconductor switch.

28. The signal generating circuit of claim 27, wherein the semiconductor switch comprises a triac.

29. The signal generating circuit of claim 28 further comprising a diac coupled between the time constant circuit and the control electrode.

30. A method for encoding a signal comprising the steps of:

coupling an AC waveform to a signal generator circuit;

encoding with the signal generator circuit the AC waveform as an encoded signal by operating one of a plurality of switches wherein each switch provides a unique portion of a cycle of the AC waveform as the encoded signal, and the number of the unique portions includes the following;

a) a half cycle of the AC waveform;

b) a portion of a half cycle of the AC waveform, the unique portion having zero crossings that are spaced closer together than zero crossings of the AC waveform and;

c) a half cycle of the AC waveform having a delayed turn-on.

31. The method of claim 30, wherein the unique portion has a pulse duration and a polarity and further comprising the step of decoding the encoded signal by sensing the duration and the polarity of the unique portion.