CP2105EK Silicon Laboratories Inc, CP2105EK Datasheet - Page 12

• Manufacturer Part Number: CP2105EK
• Description: KIT EVAL FOR CP2105
• Manufacturer: Silicon Laboratories Inc

Specifications of CP2105EK

• Main Purpose: Interface, Dual USB 2.0 to UART (RS485) Bridge
• Embedded: No
• Utilized Ic / Part: CP2105
• Primary Attributes: Full Speed (12Mbps)
• Secondary Attributes: LED Status Indicators
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3.3 V
• Product: Interface Development Tools
• For Use With/related Products: CP2105
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 336-2005

CP2105
5. USB Function Controller and Transceiver
The Universal Serial Bus (USB) function controller in the CP2105 is a USB 2.0 compliant full-speed device with
integrated transceiver and on-chip matching and pullup resistors. The USB function controller manages all data
transfers between the USB and the UARTs as well as command requests generated by the USB host controller
and commands for controlling the function of the UARTs and GPIO pins.
The USB Suspend and Resume states are supported for power management of both the CP2105 device as well as
external circuitry. The CP2105 will enter Suspend mode when Suspend signaling is detected on the bus. On
entering Suspend mode, the SUSPEND signals will be asserted if the corresponding interface is configured for
GPIO mode. SUSPEND is also asserted after a CP2105 reset until device configuration during USB Enumeration
is complete. SUSPEND is active-low by default, but can be configured using the PROM to be active high.
The CP2105 exits the Suspend mode when any of the following occur: Resume signaling is detected or generated,
a USB Reset signal is detected, or a device reset occurs. On exit of Suspend mode the SUSPEND signal is de-
asserted. SUSPEND is weakly pulled to VIO in a high impedance state during a CP2105 reset. If this behavior is
undesirable, a strong pulldown (10 k) can be used to ensure SUSPEND remains low during reset.
The logic level and output mode (push-pull or open-drain) of various pins during USB Suspend is configurable in
the PROM. See Section 9 for more information.
6. Asynchronous Serial Data Bus (UART) Interfaces
The CP2105 contains two UART interfaces, known as the Enhanced Communications Interface (ECI) and
Standard Communications Interface (SCI)
Each UART interface consists of the TXD (transmit) and RXD (receive) data signals as well as RTS and CTS flow
control signals. Optionally, the modem control signals DSR, DTR, DCD, and RI can be enabled for each interface.
If modem control signals are not required for the application, these pins can be configured to operate with alternate
functions, such as GPIO and SUSPEND signals. The UARTs support RTS/CTS, DSR/DTR, and X-On/X-Off
handshaking. The UARTs are programmable to support a variety of data formats and baud rates. The ECI supports
several additional UART configuration options beyond those supported by the SCI. If the Virtual COM Port drivers
are used, the data format and baud rate are set during COM port configuration on the PC. If the USBXpress drivers
are used, the CP2105 is configured through the USBXpress API. The data formats and baud rates available to
each interface are listed in Table 10.
12
Notes:
Parity Type
Baud Rate
Data Bits
Stop Bits
1. Data sizes of 5 and 6 bits are not supported at baud rates above 921600 bps.
2. 1.5 stop bits only available when using 5 data bits.
3. See “6.1. ECI Baud Rate Generation” for more details on possible baud rates for the ECI interface.
Interface
1
Enhanced Communication Interface (ECI)
5, 6, 7, and 8
1, 1.5
None, Even, Odd, Mark, Space
300 bps to 2.0 Mbps
2
, and 2
Table 10. Data Formats and Baud Rates
3
Rev. 1.0
8
1
2400, 4800, 7200, 9600, 14400, 19200, 28800,
38400, 56000, 57600, 115200, 128000,
230400, 460800, 921600
Standard Communication Interface (SCI)
None, Even, Odd