FT232RL USB to Serial UART Interface IC
USB to Serial Interface, SSOP-28
Aliase:FT232R, FTDI USB UART
SSOP-28 Top View
26 Pins
Pinout Table26
| Pin | Signal / Name | Type | Alternative Functions |
|---|---|---|---|
| 1 | TXD | Digital | UART Transmit Data Output (from USB host to target device) |
| 2 | DTR | Digital | DTR — Data Terminal Ready Output (Active Low; commonly used to reset Arduino bootloader) |
| 3 | RTS | Digital | RTS — Request to Send Hardware Flow Control Output (Active Low) |
| 4 | VCCIO | Power | I/O Voltage Supply (1.8V – 3.3V or 5V) — sets logic levels for all I/O pins; add 100nF bypass cap to GND |
| 5 | RXD | Digital | UART Receive Data Input (from target device) |
| 6 | RI | Digital | RI — Ring Indicator Input (Active Low, RS-232 modem status signal) |
| 7 | GND | Ground | System Ground (0V) |
| 9 | DSR | Digital | DSR — Data Set Ready Input (Active Low, RS-232 modem status signal) |
| 10 | DCD | Digital | DCD — Data Carrier Detect Input (Active Low, RS-232 modem status signal) |
| 11 | CTS | Digital | CTS — Clear to Send Hardware Flow Control Input (Active Low) |
| 12 | CBUS4 | Digital | CBUS4 — Configurable I/O (programmable via EEPROM; default: TXLED# — active-low TX activity LED) |
| 13 | CBUS2 | Digital | CBUS2 — Configurable I/O (programmable via EEPROM; options: TXDEN, PWREN#, TXLED#, RXLED#, SLEEP#, CLK48, CLK24, CLK12, CLK6, GPIO) |
| 14 | CBUS3 | Digital | CBUS3 — Configurable I/O (programmable via EEPROM; default: RXLED# — active-low RX activity LED) |
| 15 | USBD+ | Digital | USB Data Positive (D+) — connect to USB connector D+ |
| 16 | USBD- | Digital | USB Data Negative (D-) — connect to USB connector D- |
| 17 | 3V3OUT | Power | +3.3V Regulated Output (internal LDO output; can supply up to 50mA; connect 100nF bypass cap to GND; also used to set VCCIO for 3.3V I/O) |
| 18 | GND | Ground | System Ground (0V) |
| 19 | RESET | Digital | Reset Input (Active Low; internal pull-up present; add 100nF bypass cap to GND; leave unconnected if unused) |
| 20 | VCC | Power | Positive Power Supply (+5V from USB or external; add 100nF + 4.7µF bypass caps to GND) |
| 21 | GND | Ground | System Ground (0V) |
| 22 | CBUS1 | Digital | CBUS1 — Configurable I/O (programmable via EEPROM; default: RXLED# — active-low RX activity LED) |
| 23 | CBUS0 | Digital | CBUS0 — Configurable I/O (programmable via EEPROM; default: TXLED# — active-low TX activity LED) |
| 25 | AGND | Ground | Analog Ground Reference (connect to GND; used by internal USB PLL and oscillator circuits) |
| 26 | TEST | Digital | Factory Test Pin — must be tied to GND for normal operation; do not connect to VCC |
| 27 | OSCI | Digital | Crystal Oscillator Input — connect 6MHz crystal; alternatively leave NC when using internal 12MHz oscillator |
| 28 | OSCO | Digital | Crystal Oscillator Output — connect to crystal only; leave NC when using internal oscillator |