LED power-supply detection and control
A circuit detects the type of a power supply driving an LED by analyzing a signal received from the power supply. The circuit controls a behavior of the LED, such as its reaction to a dimmer or to thermal conditions, based on the determined type.
1. An apparatus comprising:
an analyzer for determining a transformer type based at least in part on a power signal received from a transformer, wherein the determined transformer type corresponds to a magnetic transformer or an electronic transformer; and
a generator for generating a control signal, based at least in part on the determined transformer type, to instruct a regulator IC to operate in one of a plurality of operating modes in accordance with the transformer type, wherein the plurality of operating modes comprise a first mode for accepting a low-frequency input voltage and a second mode for accepting a high-frequency input voltage;
wherein the apparatus is a processor, microprocessor, application-specific integrated circuit, or field-programmable gate array.
2. The apparatus of claim 1 , wherein the determined transformer type comprises a manufacturer or a model of the transformer.
3. The apparatus of claim 1 , further comprising an input/output port for communicating with at least one of the analyzer and the generator.
4. The apparatus of claim 1 , wherein the analyzer comprises a frequency analyzer for determining a frequency of the power signal.
5. The apparatus of claim 1 , further comprising a dimmer control circuit for modifying the control signal in accordance with a dimmer setting.
6. The apparatus of claim 1 , further comprising a bleeder control circuit for maintaining the transformer in an operating region by causing a load of the transformer to increase.
7. The apparatus of claim 1 , further comprising a thermal control circuit for modifying the control signal in accordance with an over-temperature condition.
8. The apparatus of claim 1 , wherein the generated control signal comprises a voltage control signal, a current control signal, or a pulse-width-modulated control signal.