USB PD 3.1 EPR Powers 24V DC Motor Drive

From: //www.eetimes.com/usb-pd-3-1-epr-powers-24v-dc-motor-drive/

Over the past few years, we have seen the adoption trend and speed of USB Type-C ports. This is especially true since the release of the USB PD (Power Delivery) 3.1 protocol, which raised the fast-charging power limit from 100 watts to 240 watts (supporting Extended Power Range, or EPR). This change has enabled USB Type-C to provide sufficient charging power for more devices, including large electronic devices that require higher-power charging, IoT devices, communication and security devices, automotive and medical devices, and more. 

In the USB PD 3.1 protocol, the EPR mode contains three fixed voltage levels of 28 volts, 36 volts, and 48 volts, as well as three Adjustable Voltage Supply (AVS). The voltages of 28 volts, 36 volts, and 48 volts in the USB PD 3.1 protocol correspond to applications using 6-, 8-, and 10-cell batteries, respectively. This allows USB PD’s to be well-suited for devices such as computers, servers, motor drives, and communication power supplies. 

Figure 1: USB Type-C and PD ecosystem expansion

It is worth noting that the USB PD 3.1 protocol brings a typical application extension: providing power supply for 24-volt DC motor drives. The main function of DC motors is to convert electrical energy into the mechanical energy needed for mechanical movement, which is usually used in power tools, toy cars, electric fans, and other devices. Data shows that in 2022 the global power tool shipments and market size were 510 million units and $57.19 billion, respectively, and it is expected that the former will exceed 700 million units and the latter $80 billion by 2026. Influenced by the development trend of cordless power tools, more and more power tools are powered by multi-series lithium battery packs, and the release of USB PD 3.1 protocol will effectively promote the development of cordless power tools and accelerate the upgrade iteration of power tools to USB PD fast charging. 

Upgrade your power tool design using a standalone PD 3.1 sink controller 

A simple way to upgrade the interface design of power tools is to use the latest 240-watt PD 3.1 sink controller HUSB238A from Hynetek Semiconductor Co., Ltd. (www.hynetek.com). The HUSB238A is a highly integrated stand-alone USB Type-C and PD sink controller. The HUSB238A integrates the CC logic, USB PD protocol, and the legacy protocols. The HUSB238A supports PPS regulation with a 20-millivolt step and AVS regulation with a 100-millivolt step. The HUSB238A can run in I2C mode and GPIO mode. In I2C mode, an I2C master can access the HUSB238A to configure settings, read back status, and perform advanced functions such as DR Swap and VDM messages. The HUSB238A supports APDO, maximum 48 volts 5 amps EPR PDO and EPR AVS in I2C mode. While in GPIO mode, the configuration is achieved via the setting pins. The HUSB238A can be configured to support maximum 28-volt, 3.25-amp, PDO via VSET and ISET pins, only two resistors are used to set the voltage and current. The ultra-low operation current of the HUSB238A helps the system to reduce the total power dissipation and is suitable for a battery application. The HUSB238A is available in QFN 3 mm x 3 mm-16L package. 

Figure 2: HUSB238A advantages

The system diagram of the HUSB238A is shown below in Figure 3. The HUSB238A communicates with the USB PD source by using a USB-C connector to achieve USB-C and PD handshakes. It can control the load switch and provide over- and undervoltage protection. By controlling the HUSB238A in I2C mode through the host, it is possible to adjust the 28-volt AVS voltage to 24, which can be supplied directly to a 24-volt DC motor. 

Figure 4: HUSB238A PD3.1 reference design board

With its small package size and highly integrated design, the HUSB238A allows engineers to quickly complete interface upgrades for power tools without additional firmware development work through the HUSB238A PD 3.1 reference design board. 

Figure 5: Examples of power tools

Connect the HUSB238A PD 3.1 reference design board to the power tool and power it with a 140-watt power supply. Start the power tool and you can see that the power tool is working properly. In practice, to achieve a power output of 240 watts (48 volts, 5 amps), an additional voltage regulation circuit (in I²C mode) can be added to the VBUS PIN of the reference design board to realize the required power output.  

Figure 6: HUSB238A system diagram in I2C mode (Max. 48V)