1. Overview

MDR69 series Car Clock Stepper Motor is a precision stepping motor design, with reduction gear ratio 1/60 for minute shaft and 1/12 for hour shaft, mainly used in automotive instrumentation or other equipments, to display time. MDR69 stepper motor can be driven by 2 sequent logic pulse signals in partial step mode with 5V ~ 10V power.

2. Main Feature

• ◆Compact appearance: Ф30mm x 8.3mm
• ◆Low consumption: operation current less than 18mA
• ◆Wide operation temperature range: -40 to 105°C
• ◆High reliability and long service life: comply with automotive industrial standards

3. Typical Application

The typical application of MDR69 series car clock stepper motor is used for luxury car with a clock. For example, MDR69-02 is used for Chrysler 300 as shown below:

4. Operating Principle

MDR69 series Clock Stepper Motor can be directly driven by a standard logic voltage level with 18mA current output capacity in partial-step driving mode. Each pulse can make 60º revolution of rotor (minute shaft rotate 1º). The bit-time sequence determines the turning direction of the motor. If the input pulse of coil voltage U_R prior to the one of U_L , MDR69 series clock motor will rotate clockwise. The time sequence diagram is as following:

Driving control circuit of partial step mode: