ELM312

Elm Electronics – Circuits for the Hobbyist

< http://www.elmelectronics.com/ >

Connection Diagram

PDIP and SOIC

(top view)

1

2

3

4

8

7

6

5

Stepper Motor Controller

The ELM312 is an interface circuit for use

between high speed logic and four phase stepper

motor driver circuits. All of the logic required to

provide stepping in two directions is contained in this

one 8 pin package.

This circuit supports only the half-step mode of

operation. This mode provides eight distinct phase

control output signals for driving a variety of motors.

For dual mode operation, the ELM310 should be

considered.

The ELM312 can be controlled by a wide variety

of circuits, due to its fully static operation. In addition

to using high speed microprocessor control, suitably

debounced mechanical switches or continuously

running oscillator circuits could also be used.

C

A

Dir

Description

• Stepper motor drive logic

• Process sequencing

• Sequential left/right LED driver

Applications

Block Diagram

1 of 5

• Low power CMOS design - typically 1mA at 5V

• Wide supply range - 3.0 to 5.5 volt operation

• Two inputs control Half step motion

• No external timing components

• Completely static operation - will maintain a step

position indefinitely

• High current drive outputs - up to 25 mA

• Very high speed - up to 25000 steps per second

Features

ELM312DSB

B

D

Step

5

D

4

Step

C

Dir

7

B

6

20msec

Startup

Timer

3

2

A

Inhibit

CW

Step