ETC CP2102

CP2102
S I N G L E - C H I P USB T O UART B R I D G E
Single-Chip USB to UART Data Transfer
Virtual COM Port Device Drivers
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
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
USBXpress™ Direct Driver Support
Example Applications
Upgrade of RS-232 legacy devices to USB
Cellular phone USB interface cable
PDA USB interface cable
USB to RS-232 serial adapter
USB Function Controller
USB Specification 2.0 compliant; full-speed (12 Mbps)
USB suspend states supported via SUSPEND pins
Asynchronous Serial Data BUS (UART)
Supply Voltage
All handshaking and modem interface signals
Data formats supported:
- Data bits: 5, 6, 7, and 8
- Stop bits: 1, 1.5, and 2
- Parity: odd, even, mark, space, no parity
Baud rates: 300 bps to 1 Mbits
576 Byte receive buffer; 640 byte transmit buffer
Hardware or X-On/X-Off handshaking supported
Event character support
Line break transmission
7
REGIN
IN
Self-powered: 3.0 to 3.6 V
USB bus powered: 4.0 to 5.25 V
Package
Lead free 28-pin QFN (5 x 5 mm)
Ordering Part Number
CP2102-GM
Temperature Range: –40 to +85 °C
CP2102
Voltage
Regulator
VDD
RST
OUT
SUSPEND
6
3
8
USB
CONNECTOR
VBUS
DD+
GND
3.3 V
VDD
GND
RI
48 MHz
Oscillator
VBUS
3
4
DCD
DTR
1
2
SUSPEND
5
4
5
6
D1 D2 D3
DD+
USB
Transceiver
USB Function
Controller
UART
640B 576B
1024B
TX
RX
EEPROM
Buffer Buffer
DSR
TXD
RXD
RTS
CTS
9
12
11
(to external circuitry
for USB suspend
states)
2
1
28
27
External RS-232
transceiver or
UART circuitry
26
25
24
23
Figure 1. Example System Diagram
Rev. 1.1 9/05
Copyright © 2005 by Silicon Laboratories
CP2102
CP2102
2
Rev. 1.1
CP2102
TA B L E O F C O N T E N TS
Section
Page
1. System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
3. Global DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
4. Pinout and Package Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
5. USB Function Controller and Transceiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6. Asynchronous Serial Data Bus (UART) Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
7. Internal EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8. Virtual Com Port Device Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
9. USBXpress Direct Driver Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
10. Voltage Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Rev. 1.1
3
CP2102
1. System Overview
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 QFN-28 package. No other external USB components are required.
The on-chip EEPROM may be used to customize the USB Vendor ID, Product ID, Product Description String,
Power Descriptor, Device Release Number, and Device Serial Number as desired for OEM applications. The
EEPROM is programmed on-board via the USB allowing the programming step to be easily integrated into the
product manufacturing and testing process.
Royalty-free Virtual COM Port (VCP) device drivers provided by Silicon Laboratories allow a CP2102-based
product to appear as a COM port to PC applications. The CP2102 UART interface implements all RS-232 signals,
including control and handshaking signals, so existing system firmware does not need to be modified. In many
existing RS-232 designs, all that is required to update the design from RS-232 to USB is to replace the RS-232
level-translator with the CP2102.
An evaluation kit for the CP2102 (Part Number: CP2102EK) is available. It includes a CP2102-based USB-toUART/RS-232 evaluation board, a complete set of VCP device drivers, USB and RS-232 cables, and full
documentation. Contact a Silicon Labs’ sales representatives or go to www.silabs.com to order the CP2102
Evaluation Kit.
4
Rev. 1.1
CP2102
2. Absolute Maximum Ratings
Table 1. Absolute Maximum Ratings
Parameter
Conditions
Min
Typ
Max
Units
Ambient temperature under bias
–55
—
125
°C
Storage Temperature
–65
—
150
°C
Voltage on any I/O Pin or RST with respect to GND
–0.3
—
5.8
V
Voltage on VDD with respect to GND
–0.3
—
4.2
V
Maximum Total current through VDD and GND
—
—
500
mA
Maximum output current sunk by RST or any I/O pin
—
—
100
mA
Note: Stresses above those listed may cause permanent damage to the device. This is a stress rating only, and functional
operation of the devices at or exceeding the conditions in the operation listings of this specification is not implied.
Exposure to maximum rating conditions for extended periods may affect device reliability.
3. Global DC Electrical Characteristics
Table 2. Global DC Electrical Characteristics
VDD = 2.7 to 3.6 V, –40 to +85 °C unless otherwise specified.
Parameter
Conditions
Supply Voltage
Min
Typ
Max
Units
3.0
3.3
3.6
V
Supply Current
VDD = 3.3 V
—
26
—
mA
Supply Current in Suspend
VDD = 3.3 V
—
330
—
µA
–40
—
+85
°C
Specified Operating Temperature Range
Table 3. UART and Suspend I/O DC Electrical Characteristics
VDD = 2.7 to 3.6 V, –40 to +85 °C unless otherwise specified.
Parameters
Output High Voltage
Output Low Voltage
Conditions
IOH = –3 mA
IOH = –10 µA
IOH = –10 mA
IOL = 8.5 mA
IOL = 10 µA
IOL = 25 mA
Min
Typ
—
VDD – 0.7
—
VDD – 0.1
VDD – 0.8
—
Max
UNITS
—
—
—
V
—
—
—
—
—
1.0
0.6
0.1
—
V
Input High Voltage
2.0
—
—
V
Input Low Voltage
—
—
0.8
V
Input Leakage Current
—
25
50
µA
Rev. 1.1
5
CP2102
4. Pinout and Package Definitions
Table 4. CP2102 Pin Definitions
Name
Pin #
Type
VDD
6
Power In
Description
3.0–3.6 V Power Supply Voltage Input.
Power Out 3.3 V Voltage Regulator Output. See <PDF link>Section 10.
GND
3
Ground
RST
9
D I/O
Device Reset. Open-drain output of internal POR or VDD monitor.
An external source can initiate a system reset by driving this pin low
for at least 15 µs.
REGIN
7
Power In
5 V Regulator Input. This pin is the input to the on-chip voltage regulator.
VBUS
8
D In
VBUS Sense Input. This pin should be connected to the VBUS signal of a USB network. A 5 V signal on this pin indicates a USB network connection.
D+
4
D I/O
USB D+
D–
5
D I/O
USB D–
TXD
26
D Out
Asynchronous data output (UART Transmit)
RXD
25
D In
Asynchronous data input (UART Receive)
CTS
23*
D In
Clear To Send control input (active low)
RTS
24*
D Out
Ready to Send control output (active low)
DSR
27*
D in
Data Set Ready control input (active low)
DTR
28*
D Out
DCD
1*
D In
Data Carrier Detect control input (active low)
RI
2*
D In
Ring Indicator control input (active low)
SUSPEND
12*
D Out
This pin is driven high when the CP2102 enters the USB suspend
state.
SUSPEND
11*
D Out
This pin is driven low when the CP2102 enters the USB suspend
state.
NC
10, 13–22
Data Terminal Ready control output (active low)
These pins should be left unconnected or tied to VDD.
*Note: Pins can be left unconnected when not used.
6
Rev. 1.1
DTR
DSR
TXD
RXD
RTS
CTS
NC
27
26
25
24
23
22
GND
28
CP2102
DCD
1
21
NC
RI
2
20
NC
GND
3
19
NC
D+
4
18
NC
D-
5
17
NC
VDD
6
16
NC
REGIN
7
15
NC
CP2102
Top View
8
9
10
11
12
13
14
VBUS
RST
NC
SUSPEND
SUSPEND
NC
NC
GND
Figure 2. QFN-28 Pinout Diagram (Top View)
Rev. 1.1
7
CP2102
14
13
12
11
15
6
16
D2
5
D2
2
17
e
4
2
20
21
22
23
24
25
26
27
DETAIL 1
28
1
18
19
E2
2
3
R
6xe
E
10
9
Table 5. QFN-28 Package
Dimensions
L
7
E2
b
8
Bottom View
6xe
D
A
A2
Side View
A1
e
A3
A
A1
A2
A3
b
D
D2
E
E2
e
L
N
ND
NE
R
AA
BB
CC
DD
DETAIL 1
CC
DD
BB
AA
Figure 3. QFN-28 Package Drawing
8
Rev. 1.1
MIN
0.80
0
0
—
0.18
—
2.90
—
2.90
—
0.45
—
—
—
0.09
—
—
—
—
MM
TYP
0.90
0.02
0.65
0.25
0.23
5.00
3.15
5.00
3.15
0.5
0.55
28
7
7
—
0.435
0.435
0.18
0.18
MAX
1.00
0.05
1.00
—
0.30
—
3.35
—
3.35
—
0.65
—
—
—
—
—
—
—
—
CP2102
0.30 mm
0.50 mm
0.85 mm
0.35 mm
0.50 mm
0.10 mm
0.20 mm
0.20 mm
0.50 mm
Top View
b
0.20 mm
D
D2
Optional
GND
Connection
L
e
E2
0.20 mm
0.30 mm
0.50 mm
0.85 mm
0.35 mm
0.10 mm
E
Figure 4. Typical QFN-28 Landing Diagram
Rev. 1.1
9
CP2102
0.30 mm
0.35 mm
0.50 mm
0.60 mm
0.20 mm
0.10 mm
0.85 mm
0.50 mm
0.20 mm
0.20 mm
0.50 mm
Top View
0.60 mm
0.30 mm
0.70 mm
b
0.20 mm
e
L
E2
0.20 mm
0.30 mm
0.50 mm
0.85 mm
0.35 mm
0.10 mm
E
Figure 5. Typical QFN-28 Solder Paste Diagram
10
Rev. 1.1
D
D2
0.40 mm
CP2102
5. USB Function Controller and Transceiver
The Universal Serial Bus function controller in the CP2102 is a USB 2.0 compliant full-speed device with integrated
transceiver and on-chip matching and pull-up resistors. The USB function controller manages all data transfers
between the USB and the UART as well as command requests generated by the USB host controller and
commands for controlling the function of the UART.
The USB Suspend and Resume signals are supported for power management of both the CP2102 device as well
as external circuitry. The CP2102 will enter Suspend mode when Suspend signaling is detected on the bus. On
entering Suspend mode, the CP2102 asserts the SUSPEND and SUSPEND signals. SUSPEND and SUSPEND
are also asserted after a CP2102 reset until device configuration during USB Enumeration is complete.
The CP2102 exits the Suspend mode when any of the following occur: (1) Resume signaling is detected or
generated, (2) a USB Reset signal is detected, or (3) a device reset occurs. On exit of Suspend mode, the
SUSPEND and SUSPEND signals are de-asserted.
Both SUSPEND and SUSPEND temporarily float high during a CP2102 reset. If this behavior is undesirable, a
strong pulldown (10 kΩ) can be used to ensure SUSPEND remains low during reset. See Figure 6 for other
recommended options.
VDD
CP2102
7
R1
4.7 kΩ
RST
SUSPEND
6
C4
4.7 µF
TANT
C2
0.1 µF
3
VDD
SUSPEND
GND
RI
Option 2
8
USB
CONNECTOR
VBUS
DD+
GND
DCD
VBUS
DTR
DSR
1
2
5
3
4
4
5
6
D1
D2
D-
TXD
D+
RXD
RTS
D3
Option 3
Option
Option
Option
Option
Option
1:
2:
3:
3:
4:
Option 1
REGIN
C1
1 µF
CTS
9
(to external circuitry
for USB suspend
states)
12
11
R2
10 kΩ
2
1
28
27
Option 4
External RS-232
transceiver or
UART circuitry
26
25
24
23
A 4.7 kΩ pull-up resistor can be added to increase noise immunity.
A 4.7 µF tantalum capacitor can be added if powering other devices from the on-chip regulator.
Avalanche transient voltage suppression diodes should be added for ESD protection .
Use Littlefuse p/n SP0503BAHT or equivalent.
10 kΩ resistor to ground to hold SUSPEND low on initial power on or device reset.
Figure 6. Typical Connection Diagram
Rev. 1.1
11
CP2102
6. Asynchronous Serial Data Bus (UART) Interface
The CP2102 UART interface consists of the TX (transmit) and RX (receive) data signals as well as the RTS, CTS,
DSR, DTR, DCD, and RI control signals. The UART supports RTS/CTS, DSR/DTR, and X-On/X-Off handshaking.
The UART is programmable to support a variety of data formats and baud rates. The data format and baud rate
programmed into the UART is set during COM port configuration on the PC. The data formats and baud rates
available are listed in Table 6.
Table 6. Data Formats and Baud Rates
Data Bits
5, 6, 7, and 8
Stop Bits
1, 1.51, and 2
Parity Type
Baud Rates
None, Even, Odd, Mark, Space
2
300, 600, 1200, 1800, 2400, 4000, 4800, 7200, 9600, 14400,
16000, 19200, 28800, 38400, 51200, 56000, 57600, 64000,
76800, 115200, 128000, 153600, 230400, 250000, 256000,
460800, 500000, 576000, 9216003
Notes:
1. 5-bit only.
2. Additional baud rates are supported. See “AN205”.
3. 7 or 8 data bits only.
7. Internal EEPROM
The CP2102 includes an internal EEPROM that may be used to customize the USB Vendor ID, Product ID,
Product Description String, Power Descriptor, Device Release Number, and Device Serial Number as desired for
OEM applications. Customization of the USB configuration data is optional. If the EEPROM is not programmed
with OEM data, the default configuration data shown in Table 7 is used. However, a unique serial number is
required for OEM applications in which it is possible for multiple CP2102-based devices to be connected to the
same PC.
The internal EEPROM is programmed via the USB. This allows the OEM's USB configuration data and serial
number to be written to the CP2102 on-board during the manufacturing and testing process. A stand-alone utility
for programming the internal EEPROM is available from Silicon Laboratories. A library of routines provided in the
form of a Windows® DLL is also available. This library can be used to integrate the EEPROM programming step
into custom software used by the OEM to streamline testing and serial number management during manufacturing.
The EEPROM has a typical endurance of 100,000 write cycles with a data retention of 100 years.
USB descriptors can be locked to prevent future modification.
Table 7. Default USB Configuration Data
Name
Value
Vendor ID
10C4h
Product ID
EA60h
Power Descriptor (Attributes) 80h
12
Power Descriptor (Max.
Power)
32h
Release Number
0100h
Serial Number
0001 (63 characters maximum)
Product Description String
“CP2102 USB to UART Bridge Controller” (126 characters maximum)
Rev. 1.1
CP2102
8. Virtual Com Port Device Drivers
The CP210x Virtual COM Port (VCP) device drivers allow a CP2102-based device to appear to the PC's
application software as an additional COM port (in addition to any existing hardware COM ports). Application
software running on the PC accesses the CP2102-based device as it would access a standard hardware COM
port. However, actual data transfer between the PC and the CP2102 device is performed over the USB. Therefore,
existing COM port applications may be used to transfer data via the USB to the CP2102-based device without
modifying the application. Contact Silicon Laboratories for the latest list of supported operating systems.
Note: Silicon Laboratories’ VCP device drivers are required for device operation and are only distributed as part of the CP2102
Evaluation Kit (Part Number: CP2102EK). Contact any of Silicon Lab’s sales representatives or go to www.silabs.com to
order the CP2102 Evaluation Kit. The CP210x drivers and programming utilities are subject to change without notice.
Subscription to the website "Auto Email Alert" system for automatic notification of updates and the use of the "Product
Update Registration" service is recommended.
9. USBXpress Direct Driver Support
The Silicon Laboratories USBXpress for CP210x Development Kit provides an alternate solution for interfacing
with CP210x devices than using the Virtual COM port. No Serial Port protocol expertise is required. Instead, a
simple, high-level application program interface (API) is used to provide simpler CP201x connectivity and
functionality.
The USBXpress for CP210x Development Kit includes Windows device drivers, Windows device driver installer
and uninstallers, and a host interface function library (host API) provided in the form of a Windows Dynamic Link
Library (DLL). The included device drivers and installation files support MS Windows 98SE/2000/XP.
10. Voltage Regulator
The CP2102 includes an on-chip 5 to 3 V voltage regulator. This allows the CP2102 to be configured as either a
USB bus-powered device or a USB self-powered device. These configurations are shown in Figure 7 and Figure 8.
When enabled, the 3 V voltage regulator output appears on the VDD pin and can be used to power external 3 V
devices. See Table 8 for the voltage regulator electrical characteristics.
Alternatively, if 3 V power is supplied to the VDD pin, the CP2102 can function as a USB self-powered device with
the voltage regulator disabled. For this configuration, it is recommended that the REGIN input be tied to the 3 V net
to disable the voltage regulator. This configuration is shown in Figure 9.
The USB max power and power attributes descriptor must match the device power usage and configuration. See
application note “AN144: CP210x Customization Guide” for information on how to customize USB descriptors for
the CP2102.
Note: It is recommended that additional decoupling capacitance (e.g., 0.1 µF in parallel with 1.0 µF) be provided on the REGIN
input.
Table 8. Voltage Regulator Electrical Specifications
–40 to +85 °C unless otherwise specified.
Parameter
Conditions
Min
Typ
Max
Units
4.0
—
5.25
V
3.0
3.3
3.6
V
VBUS Detection Input Threshold
1.0
1.8
4.0
V
Bias Current
—
90
—
µA
Input Voltage Range
Output Voltage
Output Current = 1 to 100 mA*
*Note: The maximum regulator supply current is 100 mA.
Rev. 1.1
13
CP2102
CP2102
VBUS
VBUS Sense
From VBUS
REGIN
5 V In
Voltage Regulator (REG0)
3 V Out
To 3 V
Power Net
VDD
Device
Power Net
Figure 7. Configuration 1: USB Bus-Powered
CP2102
From VBUS
VBUS
VBUS Sense
From 5 V
Power Net
REGIN
5 V In
Voltage Regulator (REG0)
3 V Out
To 3V
Power Net
VDD
Device
Power Net
Figure 8. Configuration 2: USB Self-Powered
14
Rev. 1.1
CP2102
CP2102
From VBUS
VBUS
VBUS Sense
REGIN
5 V In
Voltage Regulator (REG0)
3 V Out
From 3 V
Power Net
VDD
Device
Power Net
Figure 9. Configuration 3: USB Self-Powered, Regulator Bypassed
Rev. 1.1
15
CP2102
Document Change List
Revision 1.0 to Revision 1.1
Updated “Linux 2.40” bullet on page 1.
Changed MLP to QFN throughout.
16
Rev. 1.1
CP2102
NOTES:
Rev. 1.1
17
CP2102
CONTACT INFORMATION
Silicon Laboratories Inc.
4635 Boston Lane
Austin, TX 78735
Tel: 1+(512) 416-8500
Fax: 1+(512) 416-9669
Toll Free: 1+(877) 444-3032
Email: MCUinfo@silabs.com
Internet: www.silabs.com
The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without
notice. Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences
resulting from the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features or parameters. Silicon Laboratories reserves the right to make changes without further notice. Silicon
Laboratories makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose,
nor does Silicon Laboratories assume any liability arising out of the application or use of any product or circuit, and specifically
disclaims any and all liability, including without limitation consequential or incidental damages. Silicon Laboratories products are
not designed, intended, or authorized for use in applications intended to support or sustain life, or for any other application in which
the failure of the Silicon Laboratories product could create a situation where personal injury or death may occur. Should Buyer
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hold Silicon Laboratories harmless against all claims and damages.
Silicon Laboratories, Silicon Labs, and USBXpress are trademarks of Silicon Laboratories Inc.
Other products or brandnames mentioned herein are trademarks or registered trademarks of their respective holders
18
Rev. 1.1