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

– Windmilling support through forward

resynchronization and reverse drive

– Analog, PWM, freq. or I2C based speed input

– Active Demagnetization to reduce power losses

– Configurable motor start-up and stop options

– Closed speed/power loop options

– Anti-voltage surge (AVS) protection prevents

DC bus voltage spike during motor deceleration

• 4.5- to 35-V operating voltage (40-V abs max)

• High output current capability: 4-A peak

• Low MOSFET on-state resistance

– RDS(ON) (HS + LS) at TA = 25°C : 240-mΩ (typ.)

• Low power sleep mode

– 5-μA (maximum) at VVM = 24-V, TA = 25°C

• Speed loop accuracy: 3 with internal clock and

1 with external clock reference

• Customer-configurable non-volatile memory

(EEPROM) to store device configuration

• Supports up to 100-kHz PWM frequency for low

inductance motor support

• Does not require external current sense resistors;

uses built-in current sensing

• Built-in 3.3-V, 20-mA LDO regulator

• Built-in 3.3-V/5-V, 170-mA buck regulator

• Dedicated DRVOFF pin to disable (Hi-Z) outputs

• Spread spectrum and slew rate for EMI mitigation

• Suite of integrated protection features

– Supply under voltage lockout (UVLO)

– Supply over voltage protection (OVP)

– Motor lock detection (5 different types)

– Over current protection (OCP)

– Thermal warning and shutdown (OTW/TSD)

– Fault condition indication pin (nFAULT)

– Optional fault diagnostics over I2C interface

2 Applications

• Brushless-DC (BLDC) Motor Modules

• Robotic Vacuum Suction Motors

• Motor Cycle Fuel Pumps

• Appliance Fans and Pumps

• Automotive Fan and Blowers

• CPAP Machines

3 Description

The MCT8315A 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- to 24-V

brushless-DC motors requiring up to 4-A peak current.

The MCT8315A integrates three ½-bridges with 40-

V absolute maximum capability and a low RDS(ON)

of 240 mΩ (high-side + low-side FETs). MCT8315A

integrates power management circuits including an

voltage-adjustable buck regulator (3.3 V / 5 V, 170-

mA) and LDO (3.3 V, 20 mA) that can be used to

power external circuits.

Sensorless trapezoidal control is highly configurable

(motor start-up/stop behavior, fault handling, closed

loop operation) through register settings in a nonvolatile

EEPROM, which allows the device to operate

stand-alone once it has been configured. The

MCT8315A receives a speed command through

a PWM signal, analog voltage, variable frequency

square wave or I2C instruction. There are a large

number of protection features integrated into the

MCT8315A to protect the device, motor, and system

against fault events.