Based upon Allego Microsystem's SLA7050 Unipolar Stepper Motor Controller Chip, the MB3002 MechaBlox card is high performance and simple to use.

The MB3002 is part of the Mechablox system. It can be used alone, or combined with additional MechaBlox boards for more complex applications.

Small in size (70mmx70mm), but big in performance, The MB3002 is capable of delivering programmable drive currents in excess of 1 Amp per phase.

The MB3002 uses a Pulse Width Modulated "chopper" drive. It get's the extra performance you need out of your stepper motor without the inefficiency and excess heat of bulky "RL" drives using expensive forcing power resistors. Power level is software controlled via a 6bit DAC, giving a wide range of running torque settings, and as well as holding torque settings.

The SLA7050 controller chip is optimized for unipolar stepper motors. Phase drive is hardware encoded. Without the need for software phase encoding, this configuration gives the best step rate performance, and easiest programming.

The MB3002 has three complete digital sensor interfaces with source power and signal conditioning, compatible with slow level changing photo-interrupters, Hall effect switches, and reed switches. Typical use for these interfaces would be an step index indicator, and left and right limit detection.

In addition, one unbuffered analog input to the 10 bit ATmega8 A/D converter is provided. Provision is made on the PCB to add a bias resistor to support a Thermistor for temperature or to source VCC to a external potentiometer.

The MB3002 comes ready to use, preprogrammed with MechaView software which supports both simple standalone RS232C interface applications, or more complex networked RS485.

All software source code is available under a GPL license. The MB3002 can be reprogrammed using the inexpensive Atmel AVRISP device and free Atmel AVR Studio software (available from www.atmel.com for teaching, experimentation or other custom applications.

Specifications
CPU-	16-mHz Atmel ATMega8 8-kbytes Program Flash Memory 1-kByte Sram 512-bytes EEROM
Motor Driver-	Allegro Microsystems SLA7050
Output Current-	Programmable 6-bit DAC current control    -from 0 up to 1.0-A per phase¹
Hold Current Control-	Running and Hold power are independently programmable, and automatically switch.
Pulse Rate-	Pulse rates up to 50-ksteps/sec¹
Acceleration/Deceleration-	Programmable Trapezoid acceleration/deceleration curve.
Step Modes-	Full Step, Half Step
Motor Connector-	6 pin Molex 22-23-2061 (KK© series)
Size-	70mm x 70mm x 12mmm
Com Interfaces-	RS232C, RS485(half duplex), SPI Interface, TWI (I²S), One wire Interface.
Programming interface-	Supports 10pin AVR serial programming interface
Sensor Interfaces-	Three Optical/ Hall Effect/ Mechanical Switch compatible interfaces with analog Schmitt Trigger Comparator. One general purpose Digital or Analog input to 10bit ADC.
Input Power-	8-30VDC at 20mA (not including motor current). Input power, and individual motor phase fuses provided
Accessories-	Comes with RS232C Com Cable MB1907-001 and Power cable MB1907-002
Warranty	90 Day Limited Warranty
In stock?-	Coming soon!
¹note-	actual achievable performance is dependent upon the motor selection and drive mechanism's mechanical properties.
McGourty Associates does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied. McGourty Associates reserves the right at any time without notice to change product specifications as may be required to permit improvements in the perfomance, reliability, or manufacturability. McGOURTY ASSOCIATES’ PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS.