Apparatus with optical functionality and power management and associated methods

• US 8,912,496 B2
• Filed: 11/25/2010
• Issued: 12/16/2014
• Est. Priority Date: 04/13/2010
• Status: Active Grant

• Current Assignee: Silicon Laboratories Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Rueger, Timothy T., Hong, William, Andreas, David
• Primary Examiner(s): Porta, David
• Assistant Examiner(s): Jo, Taeho
• Application Number:
  US12/954,639
• Publication Number:
  US 20110248172A1
• Time in Patent Office: 1,482 Days
• Field of Search: 2503411-3418, 250/214.R, 250/214.P, 250/214.D, 250/214.A, 250/214, 250/214.LS, 250/214.VT, 250/214.PR, 250/214.SG, 250/214.1, 250/214.AG, 250/214.AL, 250/214.B, 250/214.C, 250/214.DC, 250/214.L, 250/214.RC, 250/214.SF, 250/214.SW
• US Class Current: 250/341.1
• CPC Class Codes: G01J 1/4204 with determination of ambient light solar light G01J2001/4266
• CPC Class Codes: G01J 1/44 Electric circuits for command of an exposure part G03B7/02
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 17/08 for measuring distance only indirect measurement G01S17/46; active triangulation systems G01S17/48
• CPC Class Codes: G01S 17/46 Indirect determination of position data
• CPC Class Codes: G01S 3/7803 Means for monitoring or calibrating
• CPC Class Codes: G01S 3/7835 using coding masks
• CPC Class Codes: G01S 7/4811 common to transmitter and receiver
• CPC Class Codes: G01S 7/4913 Circuits for detection, sampling, integration or read-out
• CPC Class Codes: G01S 7/497 Means for monitoring or calibrating
• CPC Class Codes: G01S 7/4972 Alignment of sensor
• CPC Class Codes: G01V 8/20 using multiple transmitters or receivers

Abstract

In an exemplary embodiment, an apparatus includes a sensor integrated circuit (IC) that is adapted for ambient light sensing (ALS) and/or proximity detection. The sensor integrated circuit (IC) includes an integrated analog-to-digital converter (ADC) that is adapted to convert at least one signal related to ambient light sensing (ALS) and/or proximity detection to at least one digital signal, and an integrated light emitting diode (LED) driver that is adapted to drive at least one LED. The sensor IC also includes an integrated power management unit (PMU) that is adapted to reduce power dissipation of the sensor IC by running at a low duty cycle the integrated LED driver and the integrated ADC.

Claims

1. An apparatus, comprising:

a sensor integrated circuit (IC), adapted for ambient light sensing (ALS) and/or proximity detection, the sensor integrated circuit (IC) comprising;

an integrated analog-to-digital converter (ADC) adapted to convert at least one signal related to ambient light sensing (ALS) and/or proximity detection to at least one digital signal;

an integrated light emitting diode (LED) driver adapted to drive at least one light emitting diode (LED); and

an integrated power management unit (PMU) adapted to reduce power dissipation of the sensor integrated circuit (IC) by running at a low duty cycle the integrated light emitting diode (LED) driver and the integrated analog-to-digital converter (ADC), and by suspending a controller of the sensor integrated circuit (IC).

2. The apparatus according to claim 1, wherein the integrated light emitting diode (LED) driver is adapted to provide a programmable drive current to the at least one light emitting diode (LED).

3. The apparatus according to claim 1, wherein the sensor integrated circuit (IC) further comprises an integrated photodetector adapted to detect infrared ambient light.

4. The apparatus according to claim 1, wherein the sensor integrated circuit (IC) further comprises an integrated photodetector adapted to detect visible ambient light.

5. The apparatus according to claim 1, wherein the sensor integrated circuit (IC) further comprises an integrated photodetector adapted to detect proximity of an object.

6. The apparatus according to claim 1, further comprising an integrated controller adapted to control operation of the integrated analog-to-digital converter (ADC) and the integrated light emitting diode (LED) driver.

7. The apparatus according to claim 6, wherein the integrated power management unit (PMU) is adapted to enable the controller when the integrated light emitting diode (LED) driver is to drive the at least one light emitting diode (LED).

8. The apparatus according to claim 6, wherein the integrated power management unit (PMU) is adapted to enable the integrated analog-to-digital converter (ADC) when the at least one signal related to ambient light sensing (ALS) and/or proximity detection is to be converted to the at least one digital signal.

9. A method of sensing light using a sensor integrated circuit (IC), the method comprising:

(i) running the sensor integrated circuit (IC) in a sleep mode;

(ii) running the sensor integrated circuit (IC) in a convert mode upon occurrence of at least one condition, wherein during the convert mode the sensor integrated circuit (IC) converts at least one signal related to ambient light sensing (ALS) and/or proximity detection to at least one digital signal while suspending a controller of the sensor integrated circuit (IC); and

(iii) running the sensor integrated circuit (IC) in a process mode to process the at least one digital signal.

10. The method according to claim 9, further comprising (iv) running the sensor integrated circuit (IC) back in the sleep mode.

11. The method according to claim 9, wherein the at least one condition comprises a request received from a host processor.

12. The method according to claim 9, wherein the at least one condition comprises passage of a period of time.

13. The method according to claim 9, wherein running the sensor integrated circuit (IC) in the convert mode comprises enabling at least one light emitting diode (LED).

14. The method according to claim 13, wherein running the sensor integrated circuit (IC) in the convert mode further comprises enabling an analog-to-digital converter (ADC).

15. The method according to claim 14, wherein running the sensor integrated circuit (IC) in the convert mode to perform ambient light sensing further comprises disabling at least one light emitting diode (LED).

16. The method according to claim 9, wherein running the sensor integrated circuit (IC) in the process mode comprises processing a result of converting at least one signal related to ambient light sensing (ALS) and/or proximity detection to the at least one digital signal.

17. The method according to claim 16, further comprising notifying a host processor.

18. A method of sensing light using a sensor integrated circuit (IC), the method comprising:

running a light emitting diode (LED) driver to drive at least one light emitting diode (LED);

sensing ambient light and/or reflected light from an object for proximity detection to generate at least one analog signal; and

running with a low duty cycle an analog-to-digital converter (ADC) to convert the at least one analog signal into at least one digital signal and suspending a controller of the sensor integrated circuit (IC).

19. The method according to claim 18, wherein running the light emitting diode (LED) driver further comprises providing a programmable drive current to the at least one light emitting diode (LED).

20. The method according to claim 18, further comprising processing the at least one digital signal using a controller.

21. The method according to claim 20, further comprising using the controller to control operation of the analog-to-digital converter (ADC).

22. The method according to claim 20, further comprising using the controller to control operation of the light emitting diode (LED) driver.

23. The method according to claim 18, wherein sensing ambient light and/or reflected light from an object for proximity detection further comprises sensing ambient visible light.

24. The method according to claim 18, wherein sensing ambient light and/or reflected light from an object for proximity detection further comprises sensing ambient infrared light.