MTD6508 Datasheet, PDF (1/26 Pages) Microchip Technology – 3-Phase Sinusoidal Sensorless Brushless DC Fan Motor Driver

MTD6508
3-Phase Sinusoidal Sensorless Brushless DC Fan Motor Driver
Features
• 180° Sinusoidal Drive for High Efficiency and Low
Acoustic Noise
• Position Sensorless BLDC Drivers
(no Hall Effect Sensor required)
• Integrated Power Transistors
• Supports 2V to 5.5V Power Supplies
• Variable Programming Resistor (R_PROG) Setting
to fit Motor Constant (K_M) Range from 3.25 mV/
Hz to 52 mV/Hz
• Speed Control through Power Supply Modulation
(PSM) and/or Pulse-Width Modulation (PWM)
• Built-in Frequency Generator: FG, FG/3 Output
Signal (FG/2 and FG/6 Option are available upon
request)
• Output PWM Slew Rate Control Programmable
with an External Resistor for Start-up
(Adjustable version)
• Phase Target Selection for Regulation
(Adjustable Version)
• Start-up Strength Selection (Adjustable Version)
• Start-up Output Current Controlled by PWM
• Output Current Soft Start
• Built-in Lock-up Protection and Automatic
Recovery Circuit
• Built-in Overcurrent Limitation
• Built-in Thermal Shutdown Protection
• Built-in Overvoltage Protection
• Low Minimal Start-up Speed for Low-Speed
Operation
• Packages:
- 10-Lead 3 mm x 3 mm x 0.5 mm UDFN
- 16-Lead 4 mm x 4 mm x 0.5 mm UQFN
(Adjustable version)
Applications
• Notebook CPU Cooling Fans
• 5V 3-Phase BLDC Motors
Description
The MTD6508 device is a 3-phase, full-wave
sensorless driver for brushless DC (BLDC) motors. It
features a 180° sinusoidal drive, high torque output and
silent drive. With adaptive features, parameters and a
wide range of power supplies (2V to 5.5V), the
MTD6508 is intended to cover a broad range of motor
characteristics while requiring minimum external
components. Speed control can be achieved through
either power supply modulation (PSM) or pulse-width
modulation (PWM).
Compact packaging and a minimal bill of materials
make the MTD6508 device extremely cost-efficient in
fan applications. For example, the CPU cooling fans in
notebook computers require designs that provide low
acoustic noise, low mechanical vibration and are highly
efficient. The frequency generator (FG) output enables
precision speed control in closed-loop applications.
The MTD6508 device includes Lock-up Protection
mode to turn off the output current when the motor is in
a lock condition, with an automatic recovery feature to
restart the fan when the lock condition is removed.
Motor overcurrent limitation and thermal shutdown
protection are included for safety-enhanced operations.
The MTD6508 is available in compact, thermally-
enhanced, 10-Lead 3 mm x 3 mm x 0.5 mm UDFN
packages and 16-Lead 4 mm x 4 mm x 0.5 mm
UQFN packages.
 2015 Microchip Technology Inc.
DS20005359A-page 1