Drive signal supply device and drive signal calibrating method thereof

A drive signal supply device comprising:

• an oscillation circuit including a plurality of oscillators each including inverters, and configured to output a plurality of oscillation signals, wherein a switching characteristic of each of the inverters included in one of the plurality of oscillators is different from a switching characteristic of each of the inverters included in another of the plurality of oscillators;
• a control circuit configured to detect a process corner of a semiconductor device based on the plurality of oscillation signals to generate a control signal;
• and
• a drive signal generation circuit configured to generate a drive signal for the semiconductor device based on the control signal,
• wherein the drive signal of the semiconductor device is an internal clock signal to be provided to the semiconductor device,
• wherein the control circuit is configured to determine the process corner based on a result of comparing a plurality of count values of the plurality of oscillation signals with each other,
• wherein the plurality of oscillators include:
• a first oscillator configured to output a first oscillation signal;
• a second oscillator configured to output a second oscillation signal;
• and
• a third oscillator configured to output a third oscillation signal,
• wherein each of inverters included in the first oscillator has a first ratio of channel widths, each of inverters included in the second oscillator has a second ratio of channel widths, and each of inverters included in the third oscillator has a third ratio of channel widths,
• wherein the second ratio of channel widths is greater than the first ratio of channel widths, and the third ratio of channel widths is greater than the second ratio of channel widths, and
• wherein the control circuit is configured to determine the process corner based on a result of comparing a frequency of the first oscillation signal, a frequency of the second oscillation signal, and a frequency of the third oscillation signal.

A method of calibrating a drive signal, the method comprising:

• outputting first to third oscillation signals by an oscillation circuit including first to third oscillators, wherein each of inverters included in the first oscillator has a first ratio of channel widths, each of inverters included in the second oscillator has a second ratio of channel widths, and each of inverters included in the third oscillator has a third ratio of channel widths, wherein the second ratio of channel widths is greater than the first ratio of channel widths, and the third ratio of channel widths is greater than the second ratio of channel widths;
• determining a process corner of a semiconductor device based on the first to third oscillation signals;
• and
• calibrating the drive signal as an internal clock signal to be provided to the semiconductor device based on the process corner,
• wherein the determining of the process corner comprises identifying the process corner based on a result of comparing a frequency of the first oscillation signal, a frequency of the second oscillation signal, and a frequency of the third oscillation signal.