CP2101-GMR

CP2101 Single-Chip USB to UART Bridge Single-Chip USB to UART Data Transfer - Integrated USB Transceiver; No External Resistors - Required Integrated Clock; No External Crystal Required Integrated 512-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 USBXpress™ Direct Driver Support - Royalty-Free Distribution License - Windows Vista/XP/Server 2003/2000 - Windows CE 6.0, 5.0, and 4.2 USB Function Controller - USB Specification 2.0 Compliant; Full Speed - Virtual COM Port Device Drivers - Works with Existing COM Port PC Applications - Royalty-Free Distribution License - Windows Vista/XP/Server 2003/2000/98SE - Mac OS-X/OS-9 - Linux 2.40 (12 Mbps) USB suspend states supported via SUSPEND pins Asynchronous Serial Data BUS (UART) - All Handshaking and Modem Interface Signals - Data Formats Supported: • Data Bits: 8 • Stop Bits: 1 • Parity: Odd, Even, No Parity - Baud Rates: 300 bps to 921.6 kbps - 512 Byte Receive Buffer; 512 Byte Transmit Buffer - Hardware or X-On / X-Off Handshaking Supported - Event Character 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 Supply Voltage - Self-powered: 3.0 to 3.6 V - USB Bus Powered: 4.0 to 5.25 V Package - Pb-free 28-pin QFN (5 x 5 mm) Ordering Part Number - CP2101-GM Temperature Range: -40 to +85 °C  Note: The CP2101 is a mature product and is not recommended for new designs. The CP2102 is a pin and software compatible alternative for the CP2101. The CP2102 is recommended for all new designs. CP2101 7 REGIN VDD Voltage IN Regulator RST OUT SUSPEND 6 3 8 USB CONNECTOR VBUS D– D+ GND 3.3 V VDD SUSPEND GND RI 48 MHz Oscillator VBUS DCD DTR DSR 1 5 2 3 4 4 5 6 D1 D2 D3 UART D– D+ USB Transceiver USB Function Controller 512B 512B 512B TX RX EEPROM Buffer Buffer 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 Example System Diagram Rev. 1.8 5/07 Copyright © 2007 by Silicon Laboratories CP2101 CP2101 2 Rev. 1.8 1. SYSTEM OVERVIEW ........................................................................................................ 5 2. ABSOLUTE MAXIMUM RATINGS ................................................................................... 5 Table 2.1. Absolute Maximum Ratings ............................................................................... 5 3. GLOBAL DC ELECTRICAL CHARACTERISTICS .......................................................... 6 Table 3.1. Global DC Electrical Characteristics .................................................................. 6 Table 3.2. UART and Suspend I/O DC Electrical Characteristics ...................................... 6 Table 3.3. Reset Electrical Characteristics ......................................................................... 6 4. PINOUT AND PACKAGE DEFINITIONS .......................................................................... 7 Table 4.1. Pin Definitions for the CP2101 .......................................................................... 7 Figure 4.1. QFN-28 Pinout Diagram (Top View) ................................................................ 8 Figure 4.2. QFN-28 Package Drawing ............................................................................... 9 Table 4.2. QFN-28 Package Dimensions ........................................................................... 9 Figure 4.3. Typical QFN-28 Landing Diagram ................................................................. 10 Figure 4.4. Typical QFN-28 Solder Paste Recommendation ........................................... 11 5. USB FUNCTION CONTROLLER AND TRANSCEIVER ................................................ 12 Figure 5.1. Typical Connection Diagram .......................................................................... 12 6. ASYNCHRONOUS SERIAL DATA BUS (UART) INTERFACE ..................................... 13 Table 6.1. Data Formats and Baud Rates ........................................................................ 13 7. INTERNAL EEPROM ...................................................................................................... 13 Table 7.1. Default USB Configuration Data ...................................................................... 13 8. CP2101 DEVICE DRIVERS ............................................................................................. 14 8.1. Virtual COM Port Drivers .......................................................................................... 14 8.2. USBXpress Drivers .................................................................................................. 14 8.3. Driver Customization ................................................................................................ 14 8.4. Driver Certification .................................................................................................... 14 9. VOLTAGE REGULATOR ................................................................................................ 15 Table 9.1. Voltage Regulator Electrical Specifications ..................................................... 15 Figure 9.1. Configuration 1: USB Bus-Powered .............................................................. 15 Figure 9.2. Configuration 2: USB Self-Powered .............................................................. 16 Figure 9.3. Configuration 3: USB Self-Powered, Regulator Bypassed ............................ 16 10. RELEVANT APPLICATION NOTES ............................................................................... 17 Document Change List ....................................................................................................... 18 Rev. 1.8 3 4 Rev. 1.8 CP2101 1. System Overview The CP2101 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 CP2101 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 CP2101based product to appear as a COM port to PC applications. The CP2101 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 CP2101. Direct access driver support is available through the Silicon Laboratories USBXpress driver set. The CP2101 is a mature product and is not recommended for new designs. The CP2102 is a pin and software compatible alternative for the CP2101. The CP2102 is recommended for all new designs. Contact Silicon Laboratories customer support at www.silabs.com for any questions about replacing the CP2101. 2. Absolute Maximum Ratings Table 2.1. 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 under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the devices at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. Rev. 1.8 5 CP2101 3. Global DC Electrical Characteristics Table 3.1. Global DC Electrical Characteristics VDD = 3.0 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 Current1 Normal Operation; VREG Enable — 22 26 mA Supply Current1 Suspended; VREG Enable — 78 200 µA — 200 228 µA –40 — +85 °C Supply Current - USB Pull-up2 Specified Operating Temperature Range Notes: 1. USB Pull-up Current should be added for total supply current. 2. The USB Pull-up supply current values are calculated values based on USB specifications. Table 3.2. UART and Suspend I/O DC Electrical Characteristics VDD = 3.0 to 3.6 V, -40 to +85 °C unless otherwise specified. Parameters Conditions Min Typ Max Units Output High Voltage IOH = –3 mA IOH = –10 µA IOH = –10 mA VDD – 0.7 VDD – 0.1 — — — VDD – 0.8 — — — V Output Low Voltage IOL = 8.5 mA IOL = 10 µA IOL = 25 mA — — — — — 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 Table 3.3. Reset Electrical Characteristics -40°C to +85°C unless otherwise specified. Parameter Conditions Min Typ Max Units IOL = 8.5 mA, VDD = 3.0 V to 3.6 V — — 0.6 V /RST Input High Voltage 0.7 x VDD — — V /RST Input Low Voltage — — 0.3 x VDD — 25 40 µA 15 — — µs /RST Output Low Voltage /RST Input Pull-Up Current /RST = 0.0 V Minimum /RST Low Time to Generate a System Reset 6 Rev. 1.8 CP2101 4. Pinout and Package Definitions Table 4.1. Pin Definitions for the CP2101 Name Pin # VDD 6 Type Description Power In 3.0–3.6 V Power Supply Voltage Input. Power Out 3.3 V Voltage Regulator Output. See Section 9. GND 3 RST 9 REGIN 7 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 CP2101 enters the USB suspend state. SUSPEND 11* D Out This pin is driven low when the CP2101 enters the USB suspend state. NC 10, 13–22 Ground 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. Power In 5 V Regulator Input. This pin is the input to the on-chip voltage regulator. 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. Rev. 1.8 7 DTR DSR TXD RXD RTS CTS NC 27 26 25 24 23 22 GND 28 CP2101 DCD 1 21 NC RI 2 20 NC GND 3 19 NC D+ 4 18 NC D- 5 17 NC VDD 6 16 NC 15 NC CP2101 Top View GND 12 13 14 SUSPEND NC NC 10 NC 11 9 RST SUSPEND 8 7 VBUS REGIN Figure 4.1. QFN-28 Pinout Diagram (Top View) 8 Rev. 1.8 CP2101 Figure 4.2. QFN-28 Package Drawing Table 4.2. QFN-28 Package Dimensions Dimension Min Nom Max Dimension Min Nom Max A A1 A3 0.80 0.03 0.90 0.07 0.25 REF 1.00 0.11 E2 L aaa 2.90 0.45 3.15 0.55 0.15 3.35 0.65 b D 0.18 0.25 5.00 BSC. 0.30 bbb ddd 0.10 0.05 D2 e 2.90 3.15 0.50 BSC. 3.35 eee Z 0.08 0.435 Y 0.18 E 5.00 BSC. Notes: 1. All dimensions shown are in millimeters (mm) unless otherwise noted. 2. Dimensioning and Tolerancing per ANSI Y14.5M-1994. 3. This drawing conforms to JEDEC outline MO-243, variation VHHD except for custom features D2, E2, L, Z, and Y which are toleranced per supplier designation. 4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020C specification for Small Body Components. Rev. 1.8 9 CP2101 Figure 4.3. Typical QFN-28 Landing Diagram 10 Rev. 1.8 CP2101 Figure 4.4. Typical QFN-28 Solder Paste Recommendation Rev. 1.8 11 CP2101 5. USB Function Controller and Transceiver The Universal Serial Bus function controller in the CP2101 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 CP2101 device as well as external circuitry. The CP2101 will enter Suspend mode when Suspend signaling is detected on the bus. On entering Suspend mode, the CP2101 asserts the SUSPEND and SUSPEND signals. SUSPEND and SUSPEND are also asserted after a CP2101 reset until device configuration during USB Enumeration is complete The CP2101 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 CP2101 reset. If this behavior is undesirable, a strong pulldown (10 k) can be used to ensure SUSPEND remains low during reset. See Figure 5.1 for other recommended options. VDD CP2101 7 R1 4.7 k RST SUSPEND 6 C4 4.7 F C2 0.1 F 3 Option 1 REGIN C1 1 F VDD SUSPEND GND RI 9 (to external circuitry for USB suspend states) 12 11 R2 10 k 2 Option 4 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: CTS 1 28 27 26 25 24 23 A 4.7 k pull-up resistor can be added to increase noise immunity. A 4.7 F capacitor can be added if powering other devices from the on-chip regulator. Avalanche transient voltage suppression diodes can be added for ESD protection . Use Littlefuse p/n SP0503BAHT or equivalent. 10 k resistor to ground to hold SUSPEND low on initial power on or device reset. Figure 5.1. Typical Connection Diagram 12 External RS-232 transceiver or UART circuitry Rev. 1.8 CP2101 6. Asynchronous Serial Data Bus (UART) Interface The CP2101 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/XOff handshaking. The UART is programmable to support a variety of data formats and baud rates. 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 CP2101 is configured through the USBXpress API. The data formats and baud rates available are listed in Table 6.1. Table 6.1. Data Formats and Baud Rates 7. Data Bits 8 Stop Bits 1 Parity Type None, Even, Odd Baud Rates 300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800, 38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600 Internal EEPROM The CP2101 includes an internal EEPROM that may be used to customize the USB Vendor ID (VID), Product ID (PID), Product Description String, Power Descriptor, Device Release Number and Device Serial Number as desired for OEM applications. If the EEPROM is not programmed with OEM data, the default configuration data shown in Table 7.1 is used. While customization of the USB configuration data is optional, it is recommended to customize the VID/PID combination. A unique VID/PID combination will prevent the driver from conflicting with any other USB driver. A vendor ID can be obtained from www.usb.org or Silicon Laboratories can provide a free PID for the OEM product that can be used with the Silicon Laboratories VID. It is also recommended to customize the serial number if the OEM application is one in which it is possible for multiple CP2101-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 CP2101 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. Table 7.1. Default USB Configuration Data Name Value Vendor ID 10C4h Product ID EA60h Power Descriptor (Attributes) 80h Power Descriptor (Max. Power) 32h Release Number 0100h Rev. 1.8 13 CP2101 Table 7.1. Default USB Configuration Data (Continued) Name Value Serial Number 0001 (63 characters maximum) Product Description String “CP2101 USB to UART Bridge Controller” (126 characters maximum) 8. CP2101 Device Drivers There are two sets of device drivers available for the CP2101 devices: the Virtual COM Port (VCP) drivers and the USBXpress Direct Access drivers. Only one set of drivers is necessary to interface with the device. The latest drivers are available at http://www.silabs.com/products/microcontroller/downloads.asp. 8.1. Virtual COM Port Drivers The CP2101 Virtual COM Port (VCP) device drivers allow a CP2101-based device to appear to the PC's application software as a COM port. Application software running on the PC accesses the CP2101-based device as it would access a standard hardware COM port. However, actual data transfer between the PC and the CP2101 device is performed over the USB interface. Therefore, existing COM port applications may be used to transfer data via the USB to the CP2101-based device without modifying the application. See Application Note AN197: Code for Example Code for Interfacing to a CP2102 using the Virtual COM drivers. 8.2. USBXpress Drivers The Silicon Laboratories USBXpress drivers provide an alternate solution for interfacing with CP2102 devices. 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 USBXpress driver set is recommended for new products that also include new PC software. The USBXpress interface is described in Application Note “AN169: USBXpress Programmer's Guide.” 8.3. Driver Customization In addition to customizing the device as described in Section 7. "Internal EEPROM" on page 13, the drivers and the drivers installation package can be also be customized. See Application Note “AN220: USB Driver Customization” for more information on generating customized VCP and USBXpress drivers. 8.4. Driver Certification The default drivers that are shipped with the CP2101 are Microsoft WHQL (Windows Hardware Quality Labs) certified. The certification means that the drivers have been tested by Microsoft and their latest operating systems (XP and Vista) will allow the drivers to be installed without any warnings or errors. The customized drivers that are generated using the AN220 software are not automatically certified. They must go first through the Microsoft Driver Reseller Submission process. Contact Silicon Laboratories support for assistance with this process. 14 Rev. 1.8 CP2101 9. Voltage Regulator The CP2101 includes an on-chip 5-to-3 V voltage regulator. This allows the CP2101 to be configured as either a USB bus-powered device or a USB self-powered device. These configurations are shown in Figure 9.1 and Figure 9.2. When enabled, the 3 V voltage regulator output appears on the VDD pin and can be used to power external 3V devices. See Table 9.1 for the voltage regulator electrical characteristics. Alternatively, if 3 V power is supplied to the VDD pin, the CP2101 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 9.3. The USB max power and power attributes descriptor must match the device power usage and configuration. See application note “AN144: CP2101 Customization Guide” for information on how to customize USB descriptors for the CP2101. 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 9.1. 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 TBD µA Input Voltage Range Output Current = 1 to 100 mA* Output Voltage *Note: The maximum regulator supply current is 100 mA. CP2101 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 9.1. Configuration 1: USB Bus-Powered Rev. 1.8 15 CP2101 CP2101 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 9.2. Configuration 2: USB Self-Powered CP2101 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 9.3. Configuration 3: USB Self-Powered, Regulator Bypassed 16 Rev. 1.8 CP2101 10. Relevant Application Notes The following Application Notes are applicable to the CP2101. The latest versions of these application notes and their accompanying software are available at: http://www.silabs.com/products/microcontroller/applications.asp. AN144: CP210x Device Customization Guide. This application note describes how to use the AN144 software to configure the USB parameters on the CP2101 devices. AN169: USBXpress Programmer's Guide. This application note describes the USBXpress API interface and includes example code. AN197: Serial Communications Guide for the CP210x. This application note describes how to use the standard Windows COM port function to communicate with the CP2101 and includes example code. AN220: CP210x USB Driver Customization. This application note describes how to use the AN220 software to customize the VCP or USBXpress drivers with OEM information. Rev. 1.8 17 CP2101 DOCUMENT CHANGE LIST Revision 1.6 to Revision 1.7   Updated “Linux 2.40” bullet on page 1. Changed MLP to QFN throughout. Revision 1.7 to Revision 1.71  Removed “Windows CE” bullet from page 1. Revision 1.71 to Revision 1.8          18 Added note on pages 1 and 4 regarding CP2101 not recommend for new designs. Added additional supported operating systems on page 1. Changed VDD conditions of Tables 3.1 and 3.2 from a minimum of 2.7 to 3.0 V. Added values to Table 3.1, “Global DC Electrical Characteristics,” on page 6. Updated package drawings in Figure 4.2, Figure 4.3, and Figure 4.4. Changed Figure 4.4 title. Removed tantalum requirement in Figure 5.1. Updated Section 8. "CP2101 Device Drivers" on page 14 with USBXpress, customization, and certification information. Added Section 10. "Relevant Application Notes" on page 17. Rev. 1.8 Simplicity Studio One-click access to MCU and wireless tools, documentation, software, source code libraries & more. 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