Package Includes : 1 piece CP2102 USB to Serial TTL Bridge Controller
Features :
Included USB transceiver, without external circuit device
Includes a clock circuit and power-on reset circuit
Dual power output : 3.3V and 5V
Power indicator, data reception indicator, data transmission indicator, working status indicator LEd
Meet the USB2.0 specification requirements
SUSPEND pin supports USB suspend state
With self-recovery fuse. In the event of the accidental short circuit, it can effectively protect your computer USB port and Downloader
With reset signal output, etc. directly to the Arduino board Promini download.
Asynchronous serial data bus compatible with all handshake and modulation controller interface signals
The supported data format is 8 data bits, 1 stop bit and parity bits
Connotation 512 byte receive buffer and 512 bytes transmit buffer
Supports hardware handshaking or X-ON/X-OFF
Supported operating systems:
Windows 
MAC OS-9
MAC OS
X-Windows CE
Linux 2.40 or later
Stable and reliable chipset CP2102 USB specification 2.0 compliant with full-speed 12Mbps.
Standard USB type A male and TTL 5pin connector.
5pins for 3.3V,TXD,RXD,GND and 5V
Specifications:
Baud rates 300 bps to 1.5 Mbps.
640 byte transmit buffer.
Hardware or X-On on X-Off handshaking supported
Event character support line break transmission.
USB suspend states supported via Suspend pins. 
The main chip for the CP2102, generate a virtual serial port after installing the driver 2, USB to take power, leads to the interface includes a 3.3V (<40mA), 5V, GND, TX, RX, the signal pin level is 3.3V, positive logic 3, onboard status indicator, receive indicator, the correct installation drive status indicator remains, send and receive indicator flashes when the communication baud rate, the higher the lower the brightness. Support the baud rate between 300bps ~ 1Mbps 5, the communication format support, data bits 5, 6, 7, 8. Support 1.5, 2 stop bits. Odd, even, mark, space, none parity 6, the supported operating systems, windows vista / xp / server 2003/200, Mac OS-X / OS-9, Linux 7, USB head is male, can be connected directly to a computer USB port 8, SMD components for the SMT production process, quality and stability.
Bullet points:
CP2102 USB to Serial TTL Bridge Controller
Dual power output : 3.3V and 5V
Included USB transceiver, without external circuit device
Supports hardware handshaking or X-ON/X-OFF