Single wire serial interface utilizing count of encoded clock pulses with reset

摘要

A single wire serial interface for power ICs and other devices is provided. To use the interface, a device is configured to include an EN/SET input pin. A counter within the device counts clock pulses sent to the EN/SET input pin. The output of the counter is passed to a ROM or other decoder circuit. The ROM selects an operational state for the device that corresponds to the value of the counter. In this way, control states may be selected for the device by sending corresponding clock pulses to the EN/SET pin. Holding the EN/SET pin high causes the device to maintain its operational state. Holding the EN/SET pin low for a predetermined timeout period resets the counter and causes the device to adopt a predetermined configuration (such as off) until new clock pulses are received at the EN/SET pin.

主权项

1. A power integrated circuit for controlling a light source, the power integrated circuit comprising:
a counter that generates a count value based on pulses encoded in a signal received at a single input of the power integrated circuit; output circuitry that outputs, via at least one output of the power integrated circuit, at least one lighting control state utilized to control the light source based at least in part on the count value; and sensing circuitry that determines whether the signal is high or low so that (i) the at least one lighting control state is maintained while the signal is high, and (ii) the count value is reset in response to the signal being low for a period that exceeds a predetermined timeout value, the predetermined timeout value being longer than a width of one of the pulses.