#Reference Design#50~400mA, 8~52V, Dual H-Bridge Brushed DC Motor Driver

A dual H-bridge brushed DC motor driver with a highly configurable power stage. The device is optimized to drive two different brushed DC motors with variable current limit and an internal 5 V LDO for powering peripheral devices.

The EVM includes two 555 timer circuits configured to switch at a frequency of approximately 25 kHz with independently variable duty cycles. Each 555 timer is connected to a jumper pin that allows the user to select which channel of the DRV 8704 receives the PWM signal. This analog generation of the PWM signal allows the EVM to be used standalone without the need to flash any firmware onto the microcontroller.

If the user wishes to control the EVM with an MCU, the two 10 x 1, 100 mil headers can be docked to TI's MSP430™ LaunchPad™ and controlled with any firmware provided by the user. SPI commands can be written or read by simply docking the EVM to the LaunchPad or connecting to the 4 SPI pins with another MCU.
* Attachments: User Guide.pdf
* Attachments: MDBU010A(001)_Sch Schematic Document.PDF
* Attachments: MDBU010A(001)_BOM.xls

Features:

• PWM (Pulse Width Modulation) Motor Driver

• Drives external N-channel MOSFET

• Dual DC motor PWM control interface

• Support 100% PWM duty cycle

• 8 V to 52 V operating supply voltage range

• Adjustable gate driver (4 levels)

• 50 mA to 200 mA source current

• 100 mA to 400 mA current sink

• Integrated PWM current regulation

• Flexible decay modes

• Automatic mixed decay mode

• Slow decay

• Fast decay

• Mixed decay (adjustable percentage fast)

• Highly configurable SPI

• Digitally scaled current torque DAC

• Low current sleep mode (65 μA)

• 5 V, 10 mA LDO Regulator

• VM Undervoltage Lockout (UVLO)

• Gate Driver Failure (PDF)

• Over Current Protection (OCP)

• Thermal Expansion Coefficient (TSD)

• Fault status indication pin (nFAULT)

• Fault diagnostics via SPI
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