The NJM3776 is a switch-mode (chopper), constant-current controller intended for controlling external transistors in a high current stepper motor application. The NJM3776 has two channels, one for each winding of a two-phase stepper motor. The NJM3776 is equipped with a Disable input to simplify half stepping operation. The NJM3776 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 sections each containing four outputs, two source and two sink, intended to drive an external Hbridge. Voltage supply requirements are +5 V for logic and +10 to +45 V for the outputs.