Overview

Dual MC33926 Motor Driver Carrier

Overview

The dual MC33926 motor driver carrier is a breakout board featuring two Freescale MC33926 H-bridge

ICs. It can supply up to almost 3 A continuous current per channel to two brushed DC motors at 5 – 28 V,

and it can tolerate peak currents up to 5 A per channel for a few seconds, making this a great general-

purpose motor driver for medium-sized DC motors and for differential-drive robots that use such motors.

The MC33926 supports ultrasonic (up to 20 kHz) pulse width modulation (PWM) of the motor output

voltage, which eliminates the audible switching sounds caused by PWM speed control, and a current

feedback circuit for each motor outputs an analog voltage on its respective FB pin that is proportional to

the output current. Since this board is a carrier for the Freescale Semiconductor MC33926 H-bridge, we

recommend careful reading of the MC33926 datasheet

(821k pdf).

For a single-driver version of this board, please consider the MC33926 motor driver carrier

Pinout

The default states of many of the MC33926 logic input pins requires that many external connections be

made to use this board. To reduce the number of necessary external connections, the board has seven

default-overriding jumpers. All of the default-overriding jumpers are tied to VDD, except the D1 jumpers,

which are tied to GND. All VDD jumper pads are circles; the ground jumper pads are square. Note that

the board has only one invert, slew, and enable pin; each of these three pins affects both motor drivers.

PAGE 1
Dual MC33926 Motor Driver Carrier Overview The dual MC33926 motor driver carrier is a breakout board featuring two Freescale MC33926 H-bridge ICs. It can supply up to almost 3 A continuous current per channel to two brushed DC motors at 5 – 28 V, and it can tolerate peak currents up to 5 A per channel for a few seconds, making this a great generalpurpose motor driver for medium-sized DC motors and for differential-drive robots that use such motors.
PAGE 2
PIN VIN Default State HIGH GND OUT2 OUT1 VDD LOW HIGH HIGH HIGH IN2 HIGH IN1 HIGH PWM / D2 LOW PWM / D1 HIGH SF HIGH FB LOW EN LOW SLEW LOW INV LOW Description This is the main 5 – 28 V motor power supply connection, which should typically be made to the larger VIN pad. Operation from 5 – 8 V reduces maximum current output; the device is also protected for transients up to 40 V.
PAGE 3
The current sense and status flag connections are optional, though monitoring of the status flags can allow detection of latched fault conditions. The status flags are open-drain output, so the two status flag can be wired together for applications where I/O pins are scarce and determining which motor driver is experiencing a fault condition is not necessary. Note that the default state of the enable pin, EN, is LOW, which holds both motor driver chips in a lowcurrent sleep mode.
PAGE 4
Schematic Diagram