FT232

Part: Future Technology Devices International Ltd FT232R

Type: USB UART IC

Description: The FT232R is a single-chip USB to asynchronous serial data transfer interface, supporting data rates from 300 baud to 3 Mbaud, with integrated 1024 bit EEPROM, clock generation, and 128 byte receive and 256 byte transmit buffers.

Operating Conditions:

• Supply voltage: +3.3V to +5.25V
• Operating temperature: -40°C to 85°C
• Data transfer rates: 300 baud to 3 Mbaud

Absolute Maximum Ratings:

Key Specs:

• Data transfer rates: 300 baud to 3 Mbaud
• Receive buffer size: 128 byte
• Transmit buffer size: 256 byte
• Integrated EEPROM size: 1024 bit
• 3V3OUT regulator output current: Up to 50mA
• UART and CBUS logic level range: +1.8V to +5V
• USB compliance: USB 2.0 Full Speed

Features:

• Single chip USB to asynchronous serial data transfer interface.
• Fully integrated 1024 bit EEPROM.
• Fully integrated clock generation with no external crystal required.
• Royalty-free Virtual Com Port (VCP) and Direct (D2XX) drivers.
• Configurable CBUS I/O pins.
• Integrated +3.3V level converter for USB I/O.
• Integrated level converter on UART and CBUS for interfacing to between +1.8V and +5V logic.

Applications:

• USB to RS232/RS422/RS485 Converters
• Upgrading Legacy Peripherals to USB
• Cellular and Cordless Phone USB data transfer cables and interfaces
• Interfacing MCU/PLD/FPGA based designs to USB
• USB Smart Card Readers

Package:

• 28 Pin SSOP
• 32 Pin QFN

Functional Integration. Fully integrated EEPROM, USB termination resistors, clock generation, AVCC filtering, POR and LDO regulator.

Configurable CBUS I/O Pin Options. The fully integrated EEPROM allows configuration of the Control Bus (CBUS) functionality, signal inversion and drive strength selection. There are 5 configurable CBUS I/O pins. These configurable options are

1. TXDEN - transmit enable for RS485 designs.
2. PWREN# - Power control for high power, bus powered designs.
3. TXLED# - for pulsing an LED upon transmission of data.
4. RXLED# - for pulsing an LED upon receiving data.
5. TX&RXLED# - which will pulse an LED upon transmission OR reception of data .
6. SLEEP# - indicates that the device going into USB suspend mode.
7. CLK48 / CLK24 / CLK12 / CLK6 - 48MHz, 24MHz, 12MHz, and 6MHz clock output signal options.

The CBUS pins can also be individually configured as GPIO pins, similar to asynchronous bit bang mode. It is possible to use this mode while the UART interface is being used, thus providing up to 4 general purpose I/O pins which are available during normal operation. An application note, AN232R-01, available from FTDI website (www.ftdichip.com) describes this feature.

The CBUS lines can be configured with any one of these output options by setting bits in the internal EEPROM. The device is supplied with the most commonly used pin definitions pre-programmed - see Section 8 for details.

Asynchronous Bit Bang Mode with RD# and WR# Strobes. The FT232R supports FTDI's previous chip generation bit-bang mode. In bit-bang mode, the eight UART lines can be switched from the regular interface mode to an 8-bit general purpose I/O port. Data packets can be sent to the device and they will be sequentially sent to the interface at a rate controlled by an internal timer (equivalent to the baud rate pre-scaler). With the FT232R device this mode has been enhanced by outputting the internal RD# and WR# strobes signals which can be used to allow external logic to be clocked by accesses to the bit-bang I/O bus. This option will be described more fully in a separate application note available from FTDI website (www.ftdichip.com).

Synchronous Bit Bang Mode. The FT232R supports synchronous bit bang mode. This mode differs from asynchronous bit bang mode in that the interface pins are only read when the device is written to. This makes it easier for the controlling program to measure the response to an output stimulus as the data returned is synchronous to the output data. An application note, AN232R-01, available from FTDI website (www.ftdichip.com) describes this feature.

FTDIChip-ID™. The FT232R also includes the new FTDIChip-ID™ security dongle feature. This FTDIChip-ID™ feature allows a unique number to be burnt into each device during manufacture. This number cannot be reprogrammed. This number is only readable over USB and forms a basis of a security dongle which can be used to protect any customer application software being copied. This allows the possibility of using the FT232R in a dongle for software licensing. Further to this, a renewable license scheme can be implemented based on the FTDIChip-ID™ number when encrypted with other information. This encrypted number can be stored in the user area of the FT232R internal EEPROM, and can be decrypted, then compared with the protected FTDIChip-ID™ to verify that a license is valid. Web based applications can be used to maintain product licensing this way. An application note, AN232R-02, available from FTDI website (www.ftdichip.com) describes this feature.

The FT232R is capable of operating at a voltage supply between +3.3V and +5V with a nominal operational mode current of 15mA and a nominal USB suspend mode current of 70μA. This allows greater margin for peripheral designs to meet the USB suspend mode current limit of 2.5mA. An integrated level converter within the UART interface allows the FT232R to interface to UART logic running at +1.8V, 2.5V, +3.3V or +5V.

• USB to RS232/RS422/RS485 Converters
• Upgrading Legacy Peripherals to USB
• Cellular and Cordless Phone USB data transfer cables and interfaces
• Interfacing MCU/PLD/FPGA based designs to USB
• USB Audio and Low Bandwidth Video data transfer
• PDA to USB data transfer
• USB Smart Card Readers
• USB Instrumentation

DC Characteristics (Ambient Temperature = -40°C to +85°C)

Table 5.3 UART and CBUS I/O Pin Characteristics (VCCIO = +5.0V, Standard Drive Level)

Table 5.4 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, Standard Drive Level)

Table 5.4 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, Standard Drive Level)

Table 5.5 UART and CBUS I/O Pin Characteristics (VCCIO = +2.8V, Standard Drive Level)

Table 5.6 UART and CBUS I/O Pin Characteristics (VCCIO = +1.8V, Standard Drive Level)

Table 5.7 UART and CBUS I/O Pin Characteristics (VCCIO = +5.0V, High Drive Level)

Table 5.8 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, High Drive Level)

Table 5.8 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, High Drive Level)

Table 5.9 UART and CBUS I/O Pin Characteristics (VCCIO = +2.8V, High Drive Level)

Table 5.10 UART and CBUS I/O Pin Characteristics (VCCIO = +1.8V, High Drive Level)

** Only input pins have an internal 200KΩ pull-up resistor to VCCIO

Table 5.11 RESET# and TEST Pin Characteristics

Table 5.12 USB I/O Pin (USBDP, USBDM) Characteristics

The absolute maximum ratings for the FT232R devices are as follows. These are in accordance with the Absolute Maximum Rating System (IEC 60134). Exceeding these may cause permanent damage to the device.

Table 5.1 Absolute Maximum Ratings

• If devices are stored out of the packaging beyond this time limit the devices should be baked before use. The devices should be ramped up to a temperature of +125°C and baked for up to 17 hours.

• USB to RS232/RS422/RS485 Converters
• Upgrading Legacy Peripherals to USB
• Cellular and Cordless Phone USB data transfer cables and interfaces
• Interfacing MCU/PLD/FPGA based designs to USB
• USB Audio and Low Bandwidth Video data transfer
• PDA to USB data transfer
• USB Smart Card Readers
• USB Instrumentation

Figure 9.1 SSOP-28 Package Dimensions

The FT232RL is supplied in a RoHS compliant 28 pin SSOP package. The package is lead (Pb) free and uses a 'green' compound. The package is fully compliant with European Union directive 2002/95/EC.

This package is nominally 5.30mm x 10.20mm body (7.80mm x 10.20mm including pins). The pins are on a 0.65 mm pitch. The above mechanical drawing shows the SSOP-28 package.

All dimensions are in millimetres.

The date code format is YYXX where XX = 2 digit week number, YY = 2 digit year number. This is followed by the revision number.

The code XXXXXXXXXXXX is the manufacturing LOT code. This only applies to devices manufactured after April 2009.