Measurements of multiple external components through a single pin of an integrated circuit

Patent metadata

Field	Value
Publication number	US-9521712-B1
Application number	US-201414445732-A
Country	US
Kind code	B1
Filing date	Jul 29, 2014
Priority date	Jul 29, 2013
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

Multiple measurements may be obtained via a single pin of an integrated circuit (IC) to set multiple control parameters of a light emitting diode (LED) controller within the IC. For example, a first input signal may be applied from the IC to two or more components via a single IC pin. A first output signal may be obtained from the two or more components via the single IC pin. A second input signal may be applied from the IC to the two or more components via the single IC pin, and a second output signal may be obtained from the two or more components via the single IC pin. A first parameter and a second parameter of the two or more components may be calculated based, at least in part, on the first output signal and the second output signal obtained via the single IC pin.

First claim

What is claimed is:

1. A method comprising:
applying, via a single pin of an integrated circuit, a first input signal from the integrated circuit to two or more components;
obtaining a first output signal from the two or more components via the single pin of the integrated circuit;
applying, via the single pin of the integrated circuit, a second input signal from the integrated circuit to the two or more components;
obtaining a second output signal from the two or more components via the single pin of the integrated circuit; and
calculating, by the integrated circuit, a first parameter of the two or more components and a second parameter of the two or more components based, at least in part, on the first output signal and the second output signal obtained via the single pin.

2. The method of claim 1 , wherein the first parameter is a first value of a first component of the two or more components and the second parameter is a second value of a second component of the two or more components.

3. The method of claim 1 , wherein the first parameter is a first value of a first component of the two or more components and the second parameter is a ratio of the first value to a second value of a second component of the two or more components.

4. The method of claim 1 , wherein the two or more components comprise at least a first resistor and a second resistor, and wherein calculating the first parameter comprises calculating a first resistance of the first resistor and calculating the second parameter comprises calculating a second resistance of the second resistor.

5. The method of claim 4 , wherein the step of applying the first input signal comprises applying a first current input signal below a threshold level to activate a switch coupled to at least one of the two or more components, and wherein the step of applying the second input signal comprises applying a second current input signal above a threshold level to activate the switch.

6. The method of claim 4 , wherein the step of applying the first input signal comprises applying a zero current input signal, and wherein the step of applying the second input signal comprises applying a non-zero current input signal.

7. The method of claim 6 , wherein the step of applying the second input signal comprises generating the second input signal based, at least in part, on a supply voltage that is also supplied to the two or more components.

8. The method of claim 1 , wherein the two or more components comprise at least a first resistor and a second resistor, and wherein calculating the first parameter comprises calculating a first ratio or combination of resistances of the first resistor and the second resistor and calculating the second parameter comprises calculating a second ratio or combination of resistances of the first resistor and the second resistor.

9. The method of claim 1 , wherein the two or more components comprise at least a resistor and a capacitor, and wherein the step of calculating the first parameter comprises calculating a resistance of the resistor and the step of calculating the second parameter comprises calculating a capacitance of the capacitor.

10. The method of claim 9 , wherein the step of applying the first input signal comprises applying a first input current, wherein the step of obtaining the first output signal occurs during the step of applying the first input signal, wherein the step of applying the second input signal comprises applying a second input current until a predetermined percentage of a voltage reference is reached, and wherein the step of obtaining the second output signal occurs after applying the second input current until the predetermined percentage of the voltage reference is reached.

11. The method of claim 1 , wherein the step of applying the first input signal comprises applying a first input current from a current source, and wherein the step of applying the second input signal comprises applying a second input current from the current source.

12. The method of claim 1 , wherein the step of obtaining the first output signal comprises obtaining an N-bit first output value corresponding to the first output signal, wherein N is greater than or equal to 2, wherein the step of obtaining the second output signal comprises obtaining an N-bit second output value corresponding to the second output signal, and wherein the first parameter and the second parameter comprise independent variables.

13. The method of claim 1 , wherein the two or more components are external and discrete components coupled to the single pin simultaneously.

14. An apparatus comprising:
an integrated circuit configured to be coupled to two or more external components through a single pin,
wherein the integrated circuit is configured to:
apply, via the single pin, a first input signal to the two or more components;
obtain, via the single pin, a first output signal from the two or more components;
apply, via the single pin, a second input signal to the two or more components;
obtain, via the single pin, a second output signal from the two or more components; and
calculate at least a first parameter of the two or more components and a second parameter of the two or more components based, at least in part, on the first output signal and the second output signal obtained via the single pin.

15. The apparatus of claim 14 , wherein the first parameter is a first value of a first component of the two or more components and the second parameter is a second value of a second component of the two or more components.

16. The apparatus of claim 14 , wherein the first parameter is a first value of a first component of the two or more components and the second parameter is a ratio of the first value to a second value of a second component of the two or more components.

17. The apparatus of claim 16 , wherein the integrated circuit comprises:
a current source coupled to the single pin and configured to apply the first input signal and to apply the second input signal to the single pin; and
an amplifier coupled to the single pin and configured to obtain the first output signal and to obtain the second output signal from the single pin.

18. The apparatus of claim 16 , wherein the integrated circuit is configured to obtain an N-bit first output value corresponding to the first output signal, wherein N is greater than or equal to 2, wherein the integrated circuit is configured to obtain an N-bit second output value corresponding to the second output signal, and wherein the first parameter and the second parameter comprise independent variables.

19. The apparatus of claim 16 , wherein the integrated circuit comprises a light emitting diode (LED) controller for a LED-based light bulb.

20. The apparatus of claim 19 , wherein the integrated circuit is configured to calculate at least one of an external temperature, a maximum inductor current, and a loop gain correction.

21. The apparatus of claim 16 , wherein the two or more external components are discrete components coupled to the single pin simultaneously.

22. The apparatus of claim 14 , wherein the two or more components comprise at least a first resistor and a second resistor, and wherein the first calculated parameter comprises a first resistance of the first resistor and the second calculated parameter comprises a second resistance of the second resistor.

23. The apparatus of claim 22 , wherein the integrated circuit is configured to apply the first input si

Assignees

• Cirrus Logic Inc

Inventors

• Melanson John L
• Dutta Arnab Kumar
• Hodapp Stephen
• Drakshapalli Prashanth

Classifications

• H05B45/00

  Circuit arrangements for operating light-emitting diodes [LED] · CPC title

• G01R27/2605 Primary

  Measuring capacitance (capacitive sensors G01D5/24) · CPC title

• G01R27/14

  Measuring resistance by measuring current or voltage obtained from a reference source (G01R27/16, G01R27/20, G01R27/22 take precedence) · CPC title

• G01R27/02

  Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant (by measuring phase angle only G01R25/00) · CPC title

• H05B33/0803 Primary

  Electricity · mapped topic