MP6638 2.5-16V, 1.7A Sensorless BLDC Motor Driver QFN-8

MP6638 2.5-16V, 1.7A Sensorless BLDC Motor Driver QFN-8

The MP6638 is a three-phase sensorless, brushless DC (BLDC) motor driver with integrated power MOSFETs.

Key Specifications

Features

• 2.5V to 16V Input Voltage (VCC) Operating Range
• Up to 1.7A Peak Phase Current
• Up to 1.2A Root Mean Square (RMS) Phase Current
• Sinusoidal Sensorless Control
• Integrated 330mΩ High-Side MOSFETs (HS-FETs) and Low-Side MOSFETs (LS- FETs)
• Supports 50Hz to 100kHz Pulse-Width Modulation (PWM) Input
• Power-Save Mode
• 30kHz PWM Output Frequency
• Direction Control
• Selectable 1x, 1/2x, 1/3x FG or RD Output

Typical Application Circuit

Applications

• Gaming Fans
• Notebook Fans

Design Notes

• Set dead time to match the external FET turn-off, not the datasheet typical. Too little risks shoot-through, too much distorts the current waveform at low duty cycle.
• Use a Kelvin connection for the current-sense resistor; shared copper injects switching noise straight into the sense amplifier.
• The thermal pad is the only heat path for most packages — via-stitch it to a ground plane with at least 9 vias.
• PWM frequency trades switching loss against current ripple in the motor inductance; 20 kHz keeps the drive out of the audible band.
• Add a brake or coast path so regeneration during a fast stop does not pump the supply rail.

Common Questions