USB bus interface chip: CH372


Introduction

The CH372 is a universal device interface chip for the USB bus. It is an upgraded product of the CH371 and a simplified version of the CH375 chip. At the local end, the CH372 has an 8-bit data bus and read, write, chip select control lines and interrupt output, which can be easily attached to the system bus of the microcontroller/DSP/MCU/MPU; in the computer system, the supporting software of CH372 provides a simple and easy-to-use operating interface, which communicates with the local-side MCU as if reading and writing file.

The CH372 has built-in underlying protocol for USB communication, with a convenient built-in firmware mode and flexible external firmware mode. In the built-in firmware mode, the CH372 automatically handles all transactions of the default endpoint 0. The local MCU is responsible for data exchange, so the MCU program is very simple. In external firmware mode, the external microcontroller can handle various USB requests according to needs, so that enabling devices that conform to various USB class specifications.

Features

  • Full-speed USB device interface, compatible with USB V2.0, plug and play, peripheral components only require crystals and capacitors;
  • Provides a pair of primary endpoints and a pair of secondary endpoints, support control transfers, bulk transfers, and interrupt transfers;
  • Convenient built-in firmware mode and flexible external firmware mode;
  • The built-in firmware mode shields the relevant USB protocol, automatically completes the standard USB enumeration configuration process, does not require any processing by the local end controller, and simplifies the firmware programming of the microcontroller;
  • The generic Windows driver which provides a device-level interface and provides an API application layer interface through DLL;
  • Product manufacturers can customize Vendor ID and Product ID;
  • Universal local 8-bit data bus, 4-wire control: read operation, write operation, chip select input, interrupt output;
  • Upload buffer and download buffer of primary endpoint each with 64 bytes, upload buffer and downlink buffer of secondary endpoint each with 8 bytes;
  • Support 5V power supply voltage and 3.3V power supply voltage, support low power mode;
  • The CH372 chip is a simplified version of the CH375 chip. The CH372 reduces the USB host mode and serial port communication mode on the basis of the CH375, so the hardware cost is lower, but other functions are fully compatible with the CH375, the WDM driver and dynamic link library of the CH375 can be directly used;
  • Small SSOP-20 lead-free package, compatible with RoHS, pin compatible with CH374T chip.