| 主权项 |
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; an input current sense circuit coupled to receive an input current of the LED driver circuit and to output a low-pass filtered input current sense signal representative of the input current, wherein the input current sense circuit includes a signal conditioning circuit coupled to receive the input current, and output the low-pass filtered input current sense signal, and wherein the input current comprises a bleeder current conducted through the bleeder circuit and a load current conducted through a load of the LED driver circuit; and a controller coupled to receive the low-pass filtered input current sense signal from the input current sense circuit and coupled to output a control signal to the bleeder circuit to control the bleeder current, wherein the controller is configured to:
cause, using the control signal, the bleeder circuit to conduct a variable amount of the bleeder current to cause a value of the input current to be greater than a minimum current, wherein the variable amount of the bleeder current is determined based on the low-pass filtered input current sense signal;determine that the load has been disconnected from the LED driver circuit; andin response to determining that the load has been disconnected from the LED driver circuit, causing, using the control signal, the bleeder circuit to prevent conduction of the bleeder current. |
