a control circuit is described in which a single input terminal receives digital control signals and analog control signals . in accordance with the principles of the invention , the control circuit includes an automatic power down circuit to place the control circuit into a low power draw or “ sleep ” mode whenever predetermined conditions are present . the automatic power down circuit monitors the single input terminal and when no demand for motor operation occurs for a predetermined period of time , the automatic power down circuit operates to place the control circuit into the low power draw mode .