3 4 1 2

M1

Vcc

R

1

2

0

K

R

2

T

B

A

C

1

2

.

2

n

F

C

2

5

0

0

p

F

+5V +5V

R

3

2

0

K

R

4

T

B

A

C

3

2

.

2

n

F

C

4

5

0

0

p

F

C

5

1

u

F

C6470uF

Vcc

C

7

1

u

F

C8470uF

R

5

1

0

K

R

6

1

0

K

+5V

+5V Vcc

BRAKE BRAKE

BRAKE

C9100uF

FILE: REVISION:

DRAWN BY: PAGE OF

TITLE

+5V

R

7

1

0

K

+5V

R

8

1

0

K

RA3RA2

RB6RB7

RA0RA1

RB2RB3RB4RB5

RA0RA1RA2RA3

PIC16F628

RA2/AN2/Vref1

RA3/AN3/CMP12

RA4/TOCKI/CMP23

RA5/MCLR/Vpp4

VSS5

RB0/INT6

RB1/RX/DT7

RB2/TX/CK8

RB3/CCP19

RA1/AN1 18

RA0/AN0 17

RA7/OSC1/CLKIN 16

RA6/OSC2/CLKOUT 15

VDD 14

RB7/T1OSI/PGD 13

RB6/T1OSO/T1CKI/PGC 12

RB5 11

RB4/PGM 10

U1

1

3

2

X

1

2

0

M

H

z

LMD18245T

1110

DIRECTIONBRAKE

8764

M1M2M3M4

115

141332

9

512

Vcc OUT1OUT2

DAC REFCS OUT

RCCOMP OUT

SGNDPGND

U2 LMD18245T

1110

DIRECTIONBRAKE

8764

M1M2M3M4

115

141332

9

512

Vcc OUT1OUT2

DAC REFCS OUT

RCCOMP OUT

SGNDPGND

U3

RB2RB3 RB4

RB5

+5V

RB7RB6

R

9

1

0

K

A2OUTA1OUT

B2OUTB1OUT

B

1

O

U

T

B

2

O

U

T

A

1

O

U

T

A

2

O

U

T

C

1

0

1

0

n

F

PICStep - Copyright Alan Garfield 2004V4.0Alan1 1

2

4

6

8

1

3

5

7

10

9

CONN1

2

1

CONN2

C

1

1

1

0

n

F

+5V

+5V

+5V

Controller Connector1 - Enable (Brake)2 - GND3 - Direction4 - GND5 - Step6 - GND7 - GND8 - GND9 - +5V10 - GND

2 1

J

2

2 1

J

1

C

1

2

C

1

3

C12 and C13 optionalOnly needed when using a Xtalrather than a resonator.

J1 and J2 select the stepping mode.

00 - 1/8 step01 - 1/4 step 10 - 1/2 step (w/ torque comp)11 - Full step

R2 and R4 set the coil currents using this formula :- = 20000 /

Common values can be :-200K 0.1A40K 0.5A20K 1A10K 2A8K 2.5A6.6K 3A (DO NOT EXCEED!)