As cordless power tools continue to gain market share, the industry is moving toward higher power density, lithium-battery brushless motors, lighter designs, and smarter functions. However, traditional discrete-component solutions require numerous peripheral components and complex system tuning, making it difficult to balance compact size, high power density, reliability, and low BOM cost.

To meet these demands, Geehy has introduced the G32M3114 sensorless trapezoidal power tool solution. It addresses the complex circuitry, difficult PCB routing, and high hardware costs of traditional solutions. Its highly integrated SoC architecture reduces PCB area and BOM cost. Sensorless trapezoidal and initial position detection (IPD) control improve startup torque, while flexible pulse-width adjustment supports a wide range of motor specifications.

The Geehy G32M3114 sensorless trapezoidal power tool solution is suitable for mainstream products such as electric screwdrivers, handheld drills, impact drills, electric wrenches, angle grinders, rotary hammers, electric saws, and electric shears.

G32M3114 Sensorless Trapezoidal Power Tool Solution Overview

Geehy’s sensorless trapezoidal power tool solution is built around the G32M3114 motor-control SoC, which integrates a 200V 6N gate driver and a 5V LDO. It handles bus-voltage and bus-current sampling, trigger-signal processing, three-phase back-EMF zero-crossing detection, and motor-control logic. The advanced timer (ATMR) generates three pairs of complementary PWM signals for the gate driver, which controls the power MOSFETs and enables efficient, stable operation of the brushless motor.

Block Diagram

Core Advantages of the Solution

Highly Integrated Single-Chip Drive

• 64MHz Cortex-M0+ core with a built-in multiplication/division acceleration unit for real-time sensorless trapezoidal control calculations

• Integrated 200V 6N gate driver directly drives a three-phase full-bridge N-channel MOSFET stage, eliminating the need for an external driver IC and simplifying the power-stage design

• Integrated high-precision 5V LDO provides a stable power supply without requiring an additional power-management IC

High-Precision Analog Front End

• Four integrated high-speed comparators with propagation delays below 100ns accurately detect the back-EMF zero-crossing points of the three-phase terminal voltages, enabling smooth high-speed commutation, stable torque output, and lower system EMI

• Integrated 12-bit ADC and two operational amplifiers enable high-precision sampling without external op-amps

Comprehensive Safety Protection

• 16-bit advanced timer supports six-channel complementary PWM output with programmable dead time, preventing shoot-through between high- and low-side devices and ensuring safe commutation

• Hardware brake function provides a nanosecond-level response, immediately shutting down the drive during a stall or short circuit to protect the tool and power MOSFETs

• Integrated temperature sensing and bus-voltage sampling work with hardware brake control to provide rapid protection against overcurrent, overtemperature, and undervoltage conditions

Mature Algorithm Support

• Mature sensorless trapezoidal control algorithms include IPD positioning, windmilling startup, zero-speed closed-loop startup, adaptive commutation-angle compensation, and bus-current limiting, helping shorten the product development cycle

High Voltage Rating for Demanding Operating Conditions

• The 200V voltage rating provides ample margin for 3S–5S lithium-battery platforms. It withstands voltage spikes during startup, shutdown, and stall conditions in tools such as drills and angle grinders, improving drive stability and overall system reliability

G32M3114 Sensorless Trapezoidal Power Tool Development Demo

Measured Prototype Parameters

• A drill motor operating at an electrical frequency of 950Hz reaches a calculated speed of 19,000 RPM.

• The measured overcurrent protection value is 102A, compared with a hardware threshold of 103A, resulting in a deviation of less than 1%.

G32M3114 Motor Control SoC

The G32M3114 motor-control SoC combines high integration, strong performance, and cost efficiency. It provides the processing power, functions, and peripheral resources required for high-speed motor operation while significantly shortening the product development cycle.

Designed for lithium-battery power tools, the Geehy G32M3114 sensorless trapezoidal reference design offers high integration, precise control, comprehensive protection, and faster development. Its integrated SoC architecture simplifies peripheral circuitry, reduces PCB size and BOM cost, and improves system reliability. Combined with Geehy’s proven in-house motor-control algorithms, the solution helps customers develop smaller products and move from design to mass production more quickly.