NJM3776D2

NJM3776 DUAL CONTROLLER FOR HIGH-CURRENT STEPPER MOTOR s GENERAL DESCRIPTION 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. s PACKAGE OUTLINE NJM3776D2 s FEATURES Suitable to drive any external MOS FET or bipolar power transistor Cross conduction prevented by time delay Digital filter on chip eliminates external filtering components Package DIP24 s BLOCK DIAGRAM Phase 1 Dis 1 VR1 C1 SGND 1 Pwr GND 1 1 NJM3776 VCC V CC – + RQ S Logic RC Figure 1. Block diagram + – Logic + SQ R – Phase 2 Dis2 VR2 C2 SGND 2 Pwr GND 2 T1BL T1AL T1AU T1BU VBB1 VBB2 T2BU T2AU T2AL T2BL s PIN CONFIGURATION NJM3776 Figure 2. Pin configuration PWR GND 1 1 T1BL 2 24 PWR GND 2 23 T2BL T1BU 3 22 T2BU T1AL 4 21 T2AL T1AU 5 20 T2AU VBB1 6 SGND 1 7 VR1 8 C1 9 Phase 1 10 Dis 1 11 RC 12 NJM 19 VBB 2 3776D2 18 SGND 2 17 VR2 16 C2 15 Phase 2 1...