Embodied intelligent robots are typically composed of multiple subsystems, and MOSFETs, as crucial power switching devices, play a core role in many of these subsystems. Let's take a closer look at them.：

一、 The main components of embodied intelligent robots

1、Main controller/computing unit: The "brain" of the robot. It is usually a computing platform composed of high-performance processors (such as CPU, GPU, NPU), running operating systems, AI algorithms, path planning, decision-making control, etc.

2、Perception system： The "senses" of the robot。

Sensors: Camera (vision), LiDAR/Ultrasonic Radar (distance measurement, mapping), IMU (inertial measurement unit, orientation), Encoder (motor position/velocity), Force/Torque Sensor, Microphone (sound), Touch Sensor, etc. 

Sensor interface and processing circuit: Responsible for collecting, filtering, amplifying, and converting sensor signals into digital form.

3、Musculoskeletal system： The "limbs" of the robot。

Actuator: The most crucial component is the motor (DC brushed motor, DC brushless motor, stepper motor, servo motor). It may also include hydraulic/ pneumatic actuators (more common in industrial robots or large robots). 

Driver/Power Amplifier: Converts the control signal (from the main controller) into the high current/high voltage power signal required for driving the actuator. This is the area where the MOSFET is most intensively used. 

Mechanical structure: Joints, connecting rods, gearboxes, wheels/track systems, etc.

4、Power Management System：

Battery: Usually a lithium-ion/lithium polymer battery pack. 

Charging management circuit: Controls the battery charging process. 

Voltage conversion module: Converts the battery voltage into different voltage levels required by various components of the system (such as the main control unit, sensors, drivers, etc.) (e.g. 12V, 5V, 3.3V, 1.8V, etc.). The DC-DC converter extensively uses MOSFETs. 

Power distribution and protection: The switch controls the on/off of each power supply, and provides overvoltage/overcurrent/undervoltage protection.。

5、Communication system：

Internal communication bus: CAN, I2C, SPI, UART, Ethernet, etc., connecting the main control unit with each subsystem. 

External communication: Wi-Fi, Bluetooth, 4G/5G, Ethernet, etc., are used for interaction with the cloud, other devices or users. 

Human-computer interaction: Displays, speakers, indicator lights, touch screens, voice interaction modules, etc. 

Software and algorithms: Operating system, driver programs, perception algorithms (SLAM, object detection and recognition), navigation planning algorithms, motion control algorithms, decision-making AI, applications, etc.

二、The Application and Selection Key Points of MOSFET in Intelligent Robots

The core role of MOSFET in intelligent robots is to function as an efficient, fast and controllable electronic switch or amplifier in various circuits, and is used for power control and conversion.。

1、Motor drive (motion system - driver)

1）MOSFET application

l HBridge drive circuit (brushed DC motor)

A full-bridge or half-bridge circuit is composed of 4 MOSFETs, or two sealed (N+P) MOSFETs from Shanghai Leiditech are used to precisely control the turn-on and turn-off of the MOSFETs. This allows for controlling the direction, speed (via PWM pulse width modulation) and start/stop of the motor. Switching loss and conduction loss are the key factors. The N+P sealed MOSFET is simple to drive and has a smaller circuit size. The following figure shows the sealed version.。

Three-phase inverter (brushless DC motor / permanent magnet synchronous motor): It consists of a three-phase full-bridge inverter circuit composed of 6 MOSFETs (one upper and one lower bridge arm for each phase), or three integrated MOSFETs. Through precise control of the switching sequence of the MOSFETs (usually using space vector pulse width modulation SVPWM), it generates a rotating magnetic field to drive the motor. It requires a high switching frequency, fast switching speed, and low loss.

2）Common types of MOSFETs：

l Power MOSFET: This is the primary application. Select the appropriate specification of N-channel enhancement type MOSFET based on the motor power (voltage, current).。

l Low on-resistance MOSFET: Crucial! On-resistance directly determines on-state loss and heat generation. The commonly used trench MOSFET or super junction MOSFET technologies achieve low Rds(on).。

l Fast-switching MOSFET: High switching frequency can enhance control accuracy and efficiency, and reduce motor noise (audible noise for human ears). It requires low gate charge and Miller capacitance.。

l Integrated module: To simplify the design, enhance power density and improve reliability, IPM or PIM that integrates MOSFET, gate driver and protection circuits is often used.。

3）Key parameters for selection： 

Rated voltage, rated current, on-resistance, gate charge, switching speed, thermal resistance, packaging. 

Shanghai Lebao has a variety of MOSFET models that are suitable for use in the motor drive of intelligent robots.。

2、Power Management System

1）MOSFET in power management system applications

l Synchronous rectification: DC-DC converter (step-down/step-up/buck-boost) 

Battery protection board: MOSFET is connected in series in the charging and discharging circuit of the battery group and serves as a switch. When overcharge, overdischarge, overcurrent or short circuit is detected, the MOSFET is turned off to cut off the circuit and protect the battery safety. It is required that the conduction resistance be extremely low (to reduce voltage drop loss), the switching speed be moderate, and the reliability be extremely high. 

Load switch: Controls the on-off of the subsystem power supply (such as turning off unused sensor modules to save power). The MOSFET is connected in series in the power path as a controlled switch. It is required to have low on-resistance and low off-leakage current.

2）Common types of MOSFETs used in power management

Power MOSFET: Used for the main switch of DC-DC and the synchronous rectification switch. Also aims for low Rds(on) and high switching speed. 

Low on-resistance MOSFET: Crucial in synchronous rectification and load switching. 

Specialized battery protection MOSFET: Usually of N-channel type, with extremely low on-resistance and suitable packaging for board applications. 

Low-signal MOSFET: It may be used for controlling logic or assisting in power supply switching.

3）Key parameters for selection

 Rated voltage, rated current, on-resistance, gate charge, switching speed (for switching tubes), body diode characteristics (for synchronous rectification), off-state leakage current (for load switches)。

3、Sensor interface and actuator control

1）Function

High-power sensor/actuator drive: Certain special sensors (such as high-power laser emission tubes) or actuators (such as solenoid valves, high-power LED lights) may require MOSFETs as switches to control their power supply. 

Pulse signal amplification: When driving certain sensors that require large current pulses (such as ultrasonic transmitters), MOSFETs may be used for power amplification.

2）Common types of MOSFETs：

Medium and low-power MOSFETs: Generally, the requirement for switching speed is not as high as that in motor drives. More attention is paid to on-resistance and cost. 

Logic level MOSFET: Conveniently driven directly by the GPIO of the microcontroller. For example, 2N2007。

3）Key parameters for selection：

 Rated voltage, rated current, on-resistance, gate threshold voltage. 

In summary: The core application areas of MOSFET in intelligent robots are motor drive and power management (especially in DC-DC converters for synchronous rectification). Shanghai Lebao offers various model parameters suitable for intelligent robot applications. If you have any needs, please contact the Shanghai Lebao team.。

Leiditech Electronics is committed to becoming a leading brand in electromagnetic compatibility solutions and component supply, offering products such as ESD, TVS, TSS, GDT, MOV, MOSFET, Zener, and inductors. Leiditech has an experienced R&D team that can provide personalized customization services based on customer needs, offering the best solutions to customers.