410-267 Digilent

1300 Henley Court Pullman, WA 99163 509.334.6306 www.digilentinc.com PmodSTEP Reference Manual Revised May 24, 2016 This manual applies to the PmodSTEP rev. A Overview The PmodSTEP provides a four channel drive for a stepper motor via the ST L293DD. Users may wire two pairs of channels in series to drive up to 600 mA of current per channel and can view the current status of a GPIO signal through a set of user LEDs. Features include: Stepper motor driver for 4 and 6-pin motors Can drive both motors simultaneously Multiple LEDs to indicate signal propagation Jumper for optional external power Small PCB size for flexible designs 2.8 1.3 (7.1 cm 3.3 cm) 26-pin Pmod connector with GPIO interface Follows Digilent Pmod Interface Specification Type 1 The PmodSTEP. 1 Functional Description The PmodSTEP utilizes ST s four channel driver, a L293DD, to drive stepper motors at higher currents than a system board can typically provide from their logic outputs. External test point headers and LEDs are provided for easy testing and observation of the propagation of signals. 2 Interfacing with the Pmod The PmodSTEP communicates with the host board via the GPIO protocol. This Pmod offers headers for both 4-pin and 6-pin stepper motors. Stepper motors work by alternately energizing the coils to different polarities inducing the stepper motor to rotate. 4-pin stepper motors only work in the bipolar configuration, requiring that the two inputs on each electromagnetic coil are brought to the correct logic level voltages to induce current flow in the correct direction. The 6-pin stepper Copyright Digilent, Inc. All rights reserved. DOC : 502-276 Page 1 of 2 Other product and company names mentioned may be trademarks of their respective owners. PmodSTEP Reference Manual motor header on this Pmod can be oriented for either bipolar or unipolar configuration. The two extra pins on this header provide two positive power pins as a source of current for when an input on one end of a coil is driven to a logic low voltage level. Pin Signal Description 1 SIG1 Signal 1 2 SIG2 Signal 2 3 SIG3 Signal 3 4 SIG4 Signal 4 5 GND Power Supply Ground 6 VCC Positive Power Supply 7 SIG5 Signal 5/Output 1 for the Stepper Motor 8 SIG6 Signal 6/Output 2 for the Stepper Motor 9 SIG7 Signal 7/Output 3 for the Stepper Motor 10 SIG8 Signal 8/Output 4 for the Stepper Motor 11 GND Power Supply Ground 12 VCC Positive Power Supply Table 1. Pinout description table. Any external power applied to the PmodSTEP must be within 4.5V and 36V it is recommended that Pmod is operated at 5V. 3 Physical Dimensions The pins on the pin header are spaced 100 mil apart. The PCB is 2.8 inches long on the sides parallel to the pins on the pin header and 1.38 inches long on the sides perpendicular to the pin header. Copyright Digilent, Inc. All rights reserved. Page 2 of 2 Other product and company names mentioned may be trademarks of their respective owners.