4.5V - 36V full-bridge DC motor driver cuts complexity

October 06, 2014 // By Graham Prophet
Positioning the device as the simplest and most flexible 4.5 to 36V DC-brushed motor driver available, Maxim Integrated has posted details of its MAX1487. The device features very low driver on resistance to reduce dissipated power.

The IC features a charge-pump-less design for reduced external components and low supply current. Integrated current regulation allows user-defined peak startup motor currents and requires a minimum of external components. It includes three modes of current regulation: fast decay, slow decay, and 25% current ripple modes. Current regulation based on 25% ripple simplifies the design and enables regulation independent of motor characteristics. A separate voltage sense input (SNS) reduces current-sensing errors due to parasitic trace resistance.

The MAX14871 features shoot-through protection and internal free-wheeling diodes that absorb inductive motor currents. Driver outputs are short-circuit-protected from shorts to ground, to the supply, and between M1 and M2. An active-low FAULT output signals thermal overload and overcurrents during fault conditions.

The MAX14871 is available in a 16-pin TSSOP-EP package and operates over the -40°C to +85°C temperature range. It delivers up to 2.8A peak motor-current, with 334 mΩ (typ) total bridge on-resistance. It uses 1 mA (typ) supply current at 30 kHz and 24V, and 10 µA (max) standby current at 12V. Current regulation only requires a sense resistor.

Maxim; www.maximintegrated.com/en/products/power/power-switching/MAX14871.html

In the same release are the related MAX14870 and 14872 ; The MAX14870 has PWM and direction-control inputs, while the MAX14872 has forward and reverse inputs for direction control.