USB to RS232 Converter

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The CP2102 is a highly-integrated USB-to-UART Bridge Controller providing a simple solution for updating RS-232 designs to USB using a minimum of components and PCB space. The CP2102 includes a USB 2.0 full-speed function controller, USB transceiver, oscillator, EEPROM, and asynchronous serial data bus (UART) with full modem control signals in a compact 5 x 5 mm MLP-28 package. No other external USB components are required.

However because of its small size, and it is also an MLP, a certain degree of technical difficulty welding. So we designed of this compact USB-UART module, leads to the interface including 5V, TXD, RXD, GND, CTS, RTS, which TXD, RXD can directly connected to the MCU serial port, RXD to MCU-TXD, TXD to MCU-RXD , it can also be connected to the Bluetooth module, GPS and other serial devices, CTS and RTS handshake signals as for special occasions, usually you needless, it easy for the initial product debugging. LED mounted on the drive after the often shiny. The module uses USB male seat, can be connected directly to PC USB seat can also be connected to a USB extension line.



  • Single-Chip USB to UART Data Transfer
    • Integrated USB transceiver; no external resistors required
    • Integrated clock; no external crystal required
    • Integrated 1024-Byte EEPROM for vendor ID, product ID, serial number, power descriptor, release number, and product description strings
    • On-chip power-on reset circuit
    • On-chip voltage regulator: 3.3 V output
    • 100% pin and software compatible with CP2101
  • USB Function Controller
    • USB Specification 2.0 compliant; full-speed (12 Mbps)
    • USB suspend states supported via SUSPEND pins
  • Virtual COM Port Device Drivers
    • Works with existing COM Port PC applications
    • Royalty-free distribution license
    • Windows 98 SE/2000/XP
    • MAC OS-9
    • MAC OS-X
    • Linux 2.40 and greater
  • USBXpress™ Direct Driver Support
  • Supply Voltage
    • Self-powered: 3.0 to 3.6 V
    • USB bus powered: 4.0 to 5.25 V

Application Ideas

  • Upgrade of RS-232 legacy devices to USB
  • Cellular phone USB interface cable
  • PDA USB interface cable
  • USB to RS-232 serial adapter


  • Note:
  • This product just only out to make your computer more than a serial port, with a variety of serial devices such as GPS, satellite receiver, hard drive, Bluetooth modules and other communications.
  • The new version has cancel the CTS pin.




Pin definition and Rating

Pin # Pad Type Description
VCC 1 3.3V Integrated 3.3V(+)supply with on-chip linear regulator output within 3.15-3.3V
CTS 2 CMOS input with weak internal pull-up The new version has cancel the CTS pin.
RTS 3 CMOS input with weak internal pull-up Ready to Send control output (active low)
RXD 4 CMOS input with weak internal pull-up Asynchronous data input (UART Receive)
TXD 5 CMOS output,tri-stable with weak internal pull-up Asynchronous data output (UART Transmit)
GND 6 VSS Ground port

Mechanic Dimensions





Connect to Bluetooth or GPS

Bill of Materials (BOM) /parts list

All the components used to produce the product.


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Version Tracker

Revision Descriptions Release
v1.0 Initial public release date

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See Also

Other related products and resources.


This documentation is licensed under the Creative Commons Attribution-ShareAlike License 3.0 Source code and libraries are

licensed under GPL/LGPL, see source code files for details.

External Links

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