PULSE CURRENT LED DRIVING CIRCUIT

摘要

In one embodiment, a pulse current light-emitting diode (LED) driving circuit, can include: (i) an AC power supply configured to generate an AC input; (ii) a rectifier circuit that receives the AC input voltage, and generates a DC input voltage; (iii) a sampling circuit that receives the DC input voltage, and generates a DC sense voltage; (iv) a comparison circuit that receives the DC sense voltage, and generates a first comparison signal; (v) a feedback compensating circuit that samples a current that flows through a transistor, and generates a compensation signal; (vi) a signal processing circuit that receives the first comparison signal and the compensation signal, and generates an on signal; and (vii) the transistor having a gate configured to receive the on signal, a drain configured to receive the DC input voltage, and a source coupled to a first terminal of a sampling resistor.

主权项

1. A pulse current light-emitting diode (LED) driving circuit, comprising:
a) an AC power supply configured to generate an AC input; b) a rectifier circuit configured to receive said AC input voltage, and to generate a DC input voltage; c) a sampling circuit configured to receive said DC input voltage, and to generate a DC sense voltage; d) a comparison circuit configured to receive said DC sense voltage, and to generate a first comparison signal; e) a feedback compensating circuit configured to sample a current that flows through a transistor, and to generate a compensation signal; f) a signal processing circuit configured to receive said first comparison signal and said compensation signal, and to generate an on signal, wherein said signal processing circuit comprises a filter circuit configured to smooth rising edges and falling edges of said on signal; and g) said transistor having a gate configured to receive said on signal, a drain configured to receive said DC input voltage, and a source coupled to a first terminal of a sampling resistor, wherein a second terminal of said sampling resistor is coupled to a first terminal of a load, and a second terminal of said load is coupled to ground, and wherein said transistor is turned on and a drain-source current is generated to drive said load when said on signal is active.