NJM3776

Figure 1. Block diagram

RC

NJM3776

V

CC

V

CC

S

R

Q

Logic

S

R

Q

+

–

+

–

+

–

Logic

Phase 2

Phase 1

Dis2

C2

SGND 2

Pwr GND 2

1BL

T

1AU

T

1AL

T

BB2

V

2AU

T

2AL

T

2BL

T

Dis 1

C1

SGND 1

Pwr GND 1

1

DUAL CONTROLLER FOR HIGH-CURRENT STEPPER MOTOR

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

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 H-

bridge. Voltage supply requirements are +5 V for logic and +10 to

+45 V for the outputs.

s GENERAL DESCRIPTION

s PACKAGE OUTLINE

NJM3776D2