Adaptive turn-off delay time compensation for LED controller
Abstract:
A light emitting diode controller integrated circuit includes counter circuitry having inputs coupled to a clock signal input pin, a pulse width modulated signal input pin, and a sense input pin, and has a count output coupled to a gate drive signal output to an external power transistor. The power transistor is connected in series between a power lead, a sense resistor, and a light emitting diode. The sense input pin is coupled to the series connection between the resistor and the transistor. The counter circuitry provides a Ton_delay equal to a Toff_delay of the power transistor. By counting up during a Ton_delay and down during a Toff_delay, the controller can be used with power transistors of unknown characteristics.
Public/Granted literature
Information query
Patent Agency Ranking
0/0