Designated client product This product will be discontinued its production in the near term. And it is provided for customers currently in use only, with a time limit. It can not be available for your new project. Please select other new or existing products. For more information, please contact our sales office in your region. New Japan Radio Co.,Ltd. www.njr.com NJM3777 DUAL STEPPER MOTOR DRIVER n GENERAL DESCRIPTION n PACKAGE OUTLINE The NJM3777 is a switch-mode (chopper), constant-current driver with two channels: one for each winding of a two-phase stepper motor. The NJM3777 is equipped with a Disable input to simplify half-stepping operation. The NJM3777 contains a clock oscillator, which is common for both driver channels, a set of comparators and flip-flops implementing the switching control, and two output H-bridges, including recirculation NJM3777E3(SOP24) diodes. Voltage supply requirements are + 5 V for logic and + 10 to + 45 V for the motor. Maximum output current is 900mA per channel. n FEATURES Dual chopper driver 900 mA continuous output current per channel Digital filter on chip eliminates external filtering components Package SOP24 JEDEC 300 mil (batwing) n BLOCK DIAGRAM Phase Dis V C E 1 1 R1 1 1 NJM3777 V V CC CC R Q + S M A1 Logic M B1 V MM1 + V MM2 M B2 Logic M A2 RC S Q + R Dis E Phase V C GND 2 2 R2 2 2 Figure 1. Block diagram