NEED MORE TORQUE OUT OF STEPPER MOTOR

[gpope]

NEEDORE TORQUE OUT OF STEPPER MOTOR
I have a 324 stepper motor. The spec says it has a 28 in-oz holding torque. This may be enough for my application but the arduino uno is only putting out 50 mA and the 324 motor can take up to 350 mA. Is the motor only putting out 50/350 = 1/7 so 28/7=4 in-oz ? Is there a higher amp controller and maybe bigger stepper motor. Could I use a outside power source and control that with the arduino uno. I need to rotate back and forth 90deg.

thx for any ideas ASAP
Greg


#include <AFMotor.h> // Include the Adafruit Stepper Motor Library

AF_Stepper motor(200, 2); // 200 steps per revolution, motor port No. 2

void setup() {

motor.setSpeed(5); // Set speed to 10 revolutions per minute

}

void loop() {

motor.step(40, BACKWARD, DOUBLE); // Rotate one quarter turn clockwise
motor.step(40, FORWARD, DOUBLE); // Rotate one quarter turn counterclockwise

[Franklin97355]

You need to add a transistor or mosfet to your circuit in order to get the power you need to run the steppers. You should not expect the pins on the arduino to supply more than a signal to switch another device.