1 Features
• Three-phase BLDC motor driver with integrated
sensorless motor control algorithm
– Code-free high speed Trapezoidal Control
– Supports up to 3 kHz (electrical frequency)
– Very fast start-up time (< 50 ms)
– Fast Deceleration (< 150 ms)
– Supports 120° or 150° modulation to improve
acoustic performance
– Closed loop speed or power control
– Configurable profiles for speed or power input
reference
– Windmilling support through forward
resynchronization and reverse drive
– Analog, PWM, freq. or I2C based speed input
– Configurable motor start-up and stop options
– Anti-voltage surge (AVS) protection prevents
DC bus voltage spike during motor deceleration
– Variable monitoring through DACOUT
• 4.5- to 20-V operating voltage (24-V abs max)
• High output current capability: 5-A peak
• Low MOSFET on-state resistance
– RDS(ON) (HS + LS) at TA = 25°C : 130-mΩ
• Low power sleep mode
– 7-μA (maximum) at VVM = 12-V, TA = 25°C
• Speed loop accuracy: 3% with internal clock and
1% with external clock reference
• Supports up to 100-kHz PWM frequency for low
inductance motor support
• Does not require external current sense resistor
• Built-in 3.3-V ±5%, 20-mA LDO regulator
• Spread spectrum and slew rate for EMI mitigation
• Suite of Integrated protection features
– Supply under voltage lockout (UVLO)
– Motor lock detection (5 different types)
– Over current protection (OCP)
– Over temperature warning and shutdown
(OTW/OTS)
– Fault condition indication pin (nFAULT)
– Optional fault diagnostics over I2C interface

2 Applications
• Brushless-DC (BLDC) Motor Modules
• Robotic Vacuum Suction Motors
• Server Fans
• Appliance Fans and Pumps

3 Description
The MCT8317A provides a single-chip, codefree
sensorless trapezoidal solution for customers
requiring high speed operation (up to 3 kHz electrical)
or very fast start-up time (< 50 ms) for 12-V
brushless-DC motors up to 5-A peak current. The
MCT8317A integrates three ½-bridges with 24-V
absolute maximum capability and a very low RDS(ON)
of 130 mΩ (high-side + low-side FETs). MCT8317A
also features an LDO that generates a 3.3-V voltage
rail and can source up to 20 mA to power external
circuits.
Sensorless trapezoidal control is highly configurable
through register settings ranging from motor start-up
behavior to closed loop operation. Register settings
for MCT8317A can be set in non-volatile EEPROM,
which allows the device to operate stand-alone once
it has been configured. The device receives a speed
command through a PWM input, analog voltage,
variable frequency square wave or I2C command.
There are a large number of protection features
integrated into the MCT8317A, intended to protect the
device, motor, and system against fault events.