Patent ID: 6903589

Claim:
A circuit for outputting a signal having a target slew rate, said circuit comprising: an output driver that outputs an output signal and is responsive to a slew rate control signal to increase or decrease a slew rate of the output signal; a slew rate detection circuit that compares the output signal from the output driver with a first reference voltage and generates a first comparison output signal which exhibits a voltage transition when the output signal reaches the first reference voltage, and compares the output signal with a second reference voltage and generates a second comparison output signal which exhibits a voltage transition when the output signal reaches the second reference voltage; a pulse width comparison circuit that compares a first pulse width value with a second pulse width value, the first pulse width value corresponding to a time delay difference between the voltage transition of the first comparison output and the voltage transition of the second comparison output signal, and the second pulse width value corresponding to a target slew rate of the output signal from the output driver; and a slew rate control circuit that generates the slew rate control signal in response to a signal output from the pulse width comparison circuit.