Abstract: In some examples, a device includes a built-in self-test for detecting a fault between a first light emitting diode (LED) and a second LED. The device includes a first pair of pads configured to connect to the first LED and a second pair of pads configured to connect to the second LED. The built-in self-test is configured to control a first driver and a second driver to turn on, one-by-one, respective pass switches connected to the first and second pairs of pads. The built-in self-test is configured to then determine the first and second forward voltages across the first and second LEDs. The built-in self-test can determine whether the fault exists between the first and second LEDs based on the forward voltages.

Abstract: In some examples, a device includes a built-in self-test for detecting a fault on a light emitting diode (LED) or on a driver for an LED. The device includes a pair of pads that are configured to connect to the LED. The built-in self-test is configured to control the driver to turn on a respective pass switch connected to a pad of the pair of pads. The built-in self-test is configured to then determine a voltage level at each pad of the pair of pads. The built-in self-test can determine whether the fault exists on the LED, across the first anode pad and the first cathode pad, or on the driver based on the voltage level at each pad.

Abstract: In some examples, a device includes a built-in self-test for detecting a fault on a light emitting diode (LED) or on a driver for an LED. The device includes a pair of pads that are configured to connect to the LED. The built-in self-test is configured to control the driver to turn on a respective pass switch connected to a pad of the pair of pads. The built-in self-test is configured to then determine a voltage level at each pad of the pair of pads. The built-in self-test can determine whether the fault exists on the LED, across the first anode pad and the first cathode pad, or on the driver based on the voltage level at each pad.

Abstract: In some examples, a device includes a built-in self-test for detecting a fault between a first light emitting diode (LED) and a second LED. The device includes a first pair of pads configured to connect to the first LED and a second pair of pads configured to connect to the second LED. The built-in self-test is configured to control a first driver and a second driver to turn on, one-by-one, respective pass switches connected to the first and second pairs of pads. The built-in self-test is configured to then determine the first and second forward voltages across the first and second LEDs. The built-in self-test can determine whether the fault exists between the first and second LEDs based on the forward voltages.

Abstract: The disclosure describes techniques for driving a plurality of light emitting diodes (LEDs) arranged in a parallel connection by using PWM (Pulse Width Modulation) dimming. The techniques of this disclosure describe the generation and application of a fixed phase shift map to a driver matrix based on pixel position. Each pixel corresponds to an LED light source. In the fixed phase shift map, each pixel will have a pre-defined phase shift calculated to induce a determined variation in turn-on time for geometrically neighbouring pixels to spread out current demand over time during PWM dimming.

Abstract: This disclosure includes systems, methods, and techniques for controlling a plurality of light-emitting diodes (LEDs). For example, a circuit includes a switching device, where the switching device is electrically connected to an LED of the plurality of LEDs, and where the switching device is configured to control whether the LED receives an electrical signal from a power source. Additionally, the circuit includes processing circuitry configured to receive a photocurrent signal indicative of a photocurrent value corresponding to the LED, compare the photocurrent value with a threshold photocurrent value, and control, based on the comparison of the photocurrent value with the threshold photocurrent value, an output current of the LED.

Abstract: This disclosure includes systems, methods, and techniques for controlling a plurality of light-emitting diodes (LEDs). For example, a circuit includes a switching device, where the switching device is electrically connected to an LED of the plurality of LEDs, and where the switching device is configured to control whether the LED receives an electrical signal from a power source. Additionally, the circuit includes processing circuitry configured to determine that the LED is associated with a bright failure condition by attempting to prevent the LED from receiving the electrical signal from the power source using the switching device and disable the LED in response to detecting the bright failure condition.

Abstract: A method may include, based on a plurality of duty cycles each associated with a respective one of a plurality of LEDs, determining a first set of drive schemes such that each drive scheme is associated with a respective one of the plurality of LEDs and is dependent on the duty cycle associated with the respective one of the plurality of LEDs. The method further includes driving each of the plurality of LEDs in accordance with the associated drive scheme of the first set in at least one drive cycle. Each of the plurality of drive schemes includes one or more on-times each having a phase and a duration. The method may include driving each of the plurality of LEDs in an on-state or an off-state dependent on the respective drive scheme and determining the drive scheme dependent on the drive scheme of another one of the plurality of LEDs.

Abstract: A method and a drive circuit are disclosed. The method includes: based on a plurality of duty cycles (DC(1)-DC(n)) each associated with a respective one of a plurality of LEDs, determining a first set of drive schemes such that each drive scheme is associated with a respective one of the plurality of LEDs (11-1n) and is dependent on the duty cycle (DC(1)-DC(n)) associated with the respective one of the plurality of LEDs (11-1n); and in at least one drive cycle (TPWM), driving each of the plurality of LEDs (11-1n) in accordance with the associated drive scheme of the first set.

Abstract: Current source regulation circuitry that is arranged in a loop with power supply circuitry and current source circuitry. The current source regulation circuitry is configured to control the magnitude of supply voltage output by the power supply circuitry in order to maintain the voltage drop across each one current source of the current source circuitry to within a bounded range of voltage values. The bounded range of voltage values may be defined such that each one current source of the current source circuitry can properly regulate a drive current that is supplied to a corresponding light source coupled thereto, and such that the amount of power dissipated by each current source of the current source circuitry during operation is maintained within an acceptable range.