Patent ID: 9332614
Filing Date: 2016-05-03
CPC Classification: H05B

Claim Text:
1. A bleeder and load disconnect detection circuit for a light-emitting diode (LED) driver circuit, the bleeder and load disconnect detection circuit comprising: a bleeder circuit coupled between first and second input terminals of a dc-dc converter of the LED driver circuit to conduct a bleeder current; a bleeder current sense circuit coupled between the bleeder circuit and the second input terminal of the dc-dc converter of the LED driver circuit, wherein the bleeder current of the bleeder circuit is conducted through the bleeder current sense circuit, wherein the bleeder current sense circuit is coupled to output a bleeder current sense signal representative of the bleeder current; an input current sense circuit coupled to the bleeder current sense circuit and coupled to the second input terminal of the dc-dc converter of the LED driver circuit to receive an input current of the dc-dc converter of the LED driver circuit, wherein the input current comprises the bleeder current received from the bleeder current sense circuit, and a load current conducted through a load coupled to the dc-dc converter of the LED driver circuit, wherein the input current sense circuit includes a signal conditioning circuit coupled to receive the input current, wherein the input current sense circuit is coupled to output a low-pass filtered input current sense signal representative of the input current; and a controller coupled to receive the bleeder current sense signal from the bleeder current sense circuit, and the low-pass filtered input current sense signal from the input current sense circuit, wherein the controller is coupled to output a control signal to the bleeder circuit to control the bleeder current,