Apparatus and method for estimating motor RPM in electronic brake system

A method for estimating a motor rotation per minute (RPM) in an electronic brake system, comprising:

• detecting and amplifying, by a current signal amplifier, a signal waveform of a voltage applied across a motor driver by a current which flows while the motor driver is turned on, the motor driver being included in a motor driving circuit configured to apply motor driving power to a motor or remove the motor driving power according to a switch-on/off of the motor driver;
• detecting, by a controller, a waveform with a one-period time from periodically repeated waveforms by processing the signal waveform amplified by the current signal amplifier;
• calculating, by the controller, a one-rotation time by multiplying the one-period time by a number of commutators of the motor;
• and
• calculating, by the controller, a motor RPM using the one-rotation time.