SPMD250STP

Pin connection

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Table 3.

Pin description

N°

Name

Function

1

GND1

Return path for the logic signals and 5 V supply.

2

Sync

Chopper oscillator output. Several modules can be synchronized by

connecting together all Sync pins. This pin can be used as the input for an

external clock source.

3

Reset

Asynchronous reset input. An active low pulse on this input preset the internal

logic to the initial state (ABCD = 0101).

4

Half/Full

Half/Full step selection input. When high or unconnected the half step

operation is selected.

5

Home

When high, this output indicates that the internal counter is in its initial state

(ABCD = 0101). This signal may be used in conjunction with a mechanical

switch to ground or with open collector output of an optical detector to be used

as a system home detector.

6

Stepcl

The motor is moved one step on the rising edge of this signal.

7

CW/CCW

Direction control input. When high or unconnected clockwise rotation is

selected. Physical direction of motor rotation depends also on windings

connection.

8

Oscillator

The chopper oscillator timing, internally fixed at 17 kHz, can be modified by

connecting a resistor between this pin and Vss or a capacitor between this pin

and Gnd1. The oscillator input must be grounded when the unit is externally

synchronized.

9

Ioset

Phase current setting input. A resistor connected between this pin and Gnd1 or

Vss, allows the factory setted phase current value ( 2 A for SPMD250STP) to

be changed.

10

Control

Logic input that allows the phase current decay mode selection. When high or

unconnected the slow decay is selected.

11

Enable

Module enable input. When low this input floats the outputs enabling the

manual positioning of the motor. Must be LOW during power-up and down

sequence, HIGH during normal operation.

12

Vss

5V supply input. Maximum voltage must not exceed 7 V.

13

GND2

Return path for the power section.

14

D

D output.

15

C

C output.

16

B

B output.

17

A

A output.

18

Vs

Module and motor supply voltage. Maximum voltage must not exceed the

specified values.