Electric bicycle driving apparatus

An electric bicycle driving apparatus comprising:

• a speed change mode operator to selectively output one of a first speed change mode signal and a second speed change mode signal;
• a controller to receive the first speed change mode signal or second speed change mode signal output from the speed change mode operator and output a first control signal corresponding to the first speed change mode signal or a second control signal corresponding to the second speed change mode signal;
• a motor driver to, when the speed change mode operator outputs the first speed change mode signal, receive the first control signal and output a first motor driving signal to drive a motor in a first speed change mode, and, when the speed change mode operator outputs the second speed change mode signal, receive the second control signal and output a second motor driving signal to drive the motor, the motor rotating with a driving force of the first motor driving signal, in a second speed change mode;
• and
• a relay to selectively receive a relay switching enable signal from the controller, the relay being turned on in response to the relay switching enable signal to provide at least one of the first motor driving signal and second motor driving signal to the motor,
• wherein the relay further includes at least one Zener Diode to cut off an abnormal signal from at least one of the motor driver and the motor.