component
FT231XQ-T
Public Made by Adomby adom
FTDI USB ICs, QFN-20-EP(4x4). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
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FT231XQ-T
FTDI · USB ICs · QFN-20-EP(4x4)
FT231XQ-T from FTDI, in a QFN-20-EP(4x4). Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | RXD | input | Receiving asynchronous data input. |
| 2 | RI# | input | Ring Indicator input for remote wake up. |
| 3 | GND | power_in | 0V ground input. |
| 4 | DSR# | input | Data Set Ready control input / handshake signal. |
| 5 | DCD# | input | Data Carrier Detect control input. |
| 6 | CTS# | input | Clear To Send control input / handshake signal. |
| 7 | CBUS2 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is TXLED#. |
| 8 | USBDP | bidirectional | USB Data Signal Plus. |
| 9 | USBDM | bidirectional | USB Data Signal Minus. |
| 10 | 3V3OUT | power_out | 3V3 output at 50mA that may be used to power VCCIO; when VCC is 3V3 this pin is an input and should be connected to pin 12. |
| 11 | RESET# | input | Reset input (active low). |
| 12 | VCC | power_in | 5 V or 3V3 supply to the IC; if VCC is 3V3 then 3V3OUT must also be driven with 3V3. |
| 13 | GND | power_in | 0V ground input. |
| 14 | CBUS1 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is RXLED#. |
| 15 | CBUS0 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is TXDEN. |
| 16 | CBUS3 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is SLEEP#. |
| 17 | TXD | output | Transmit asynchronous data output. |
| 18 | DTR# | output | Data Terminal Ready control output / handshake signal. |
| 19 | RTS# | output | Request to Send control output / handshake signal. |
| 20 | VCCIO | power_in | 1V8 to 3V3 supply for the IO cells. |
| 21 | GND | power_in | Exposed pad under the centre of the package, to be connected to GND. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | FTDI |
| Package | QFN-20-EP(4x4) |
| Category | Interface ICs |
| Pins | 21 |
Electrical characteristics
Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Storage Temperature | -65 | 150 | °C | 16 | |||
| Ambient Operating Temperature (Power Applied) | -40 | 85 | °C | Power Applied | 16 | ||
| VCC Supply Voltage | VCC | -0.3 | 5.5 | V | 16 | ||
| VCCIO IO Voltage | VCCIO | -0.3 | 4 | V | 16 | ||
| DC Input Voltage, USBDP and USBDM | -0.5 | 3.63 | V | 16 | |||
| DC Input Voltage, High Impedance Bi-directionals | -0.3 | 5.8 | V | powered from VCCIO | 16 | ||
| DC Output Current, Outputs | 22 | mA | 16 | ||||
| VCC Operating Supply Voltage | VCC | 2.97 | 5 | 5.5 | V | Normal Operation | 17 |
| VCCIO Operating Supply Voltage | VCCIO | 1.62 | 3.63 | V | 17 | ||
| Operating Supply Current | Icc1 | 8 | 8 | 8.4 | mA | Normal Operation | 17 |
| Operating Supply Current (USB Suspend) | Icc2 | 125 | μA | USB Suspend | 17 | ||
| 3.3v regulator output | 3V3 | 2.97 | 3.3 | 3.63 | V | VCC must be greater than 3V3 otherwise 3V3OUT is an input which must be driven with 3.3V | 17 |
| Output Voltage High (VCCIO=3.3V) | Voh | 2.97 | V | Ioh = +/-2mA; I/O Drive strength = 4mA | 18 | ||
| Output Voltage Low (VCCIO=3.3V) | Vol | 0 | 0.4 | V | Iol = +/-2mA; I/O Drive strength = 4mA | 18 | |
| Input low Switching Threshold (VCCIO=3.3V) | Vil | 0.8 | V | LVTTL | 18 | ||
| Input High Switching Threshold (VCCIO=3.3V) | Vih | 2 | V | LVTTL | 18 | ||
| Input pull-up resistance (VCCIO=3.3V) | Rpu | 40 | 75 | 190 | KΩ | Vin = 0 | 18 |
| Input pull-down resistance (VCCIO=3.3V) | Rpd | 40 | 75 | 190 | KΩ | Vin =VCCIO | 18 |
| Input Leakage Current (VCCIO=3.3V) | Iin | -10 | 1 | 10 | μA | Vin = 0 | 18 |
| Tri-state output leakage current (VCCIO=3.3V) | Ioz | -10 | 1 | 10 | μA | Vin = 5.5V or 0 | 18 |
| Output Voltage High (VCCIO=2.5V) | Voh | 2.25 | V | Ioh = +/-2mA; I/O Drive strength = 4mA | 19 | ||
| Output Voltage Low (VCCIO=2.5V) | Vol | 0 | 0.4 | V | Iol = +/-2mA; I/O Drive strength = 4mA | 19 | |
| Input low Switching Threshold (VCCIO=2.5V) | Vil | 0.8 | V | LVTTL | 19 | ||
| Input High Switching Threshold (VCCIO=2.5V) | Vih | 0.8 | V | LVTTL | 19 | ||
| Input pull-up resistance (VCCIO=2.5V) | Rpu | 40 | 75 | 190 | KΩ | Vin = 0 | 19 |
| Input pull-down resistance (VCCIO=2.5V) | Rpd | 40 | 75 | 190 | KΩ | Vin =VCCIO | 19 |
| Input Leakage Current (VCCIO=2.5V) | Iin | -10 | 1 | 10 | μA | Vin = 0 | 19 |
| Tri-state output leakage current (VCCIO=2.5V) | Ioz | -10 | 1 | 10 | μA | Vin = 5.5V or 0 | 19 |
| Output Voltage High (VCCIO=1.8V) | Voh | 1.62 | V | Ioh = +/-2mA; I/O Drive strength = 4mA | 20 | ||
| Output Voltage Low (VCCIO=1.8V) | Vol | 0 | 0.4 | V | Iol = +/-2mA; I/O Drive strength = 4mA | 20 | |
| Input low Switching Threshold (VCCIO=1.8V) | Vil | 0.77 | V | LVTTL | 20 | ||
| Input High Switching Threshold (VCCIO=1.8V) | Vih | 1.6 | V | LVTTL | 20 | ||
| Input pull-up resistance (VCCIO=1.8V) | Rpu | 40 | 75 | 190 | KΩ | Vin = 0 | 20 |
| Input pull-down resistance (VCCIO=1.8V) | Rpd | 40 | 75 | 190 | KΩ | Vin =VCCIO | 20 |
| Input Leakage Current (VCCIO=1.8V) | Iin | -10 | 1 | 10 | μA | Vin = 0 | 20 |
| Tri-state output leakage current (VCCIO=1.8V) | Ioz | -10 | 1 | 10 | μA | Vin = 5.5V or 0 | 20 |
| Output Voltage Low (USBDP, USBDM) | Vol | 0.2 | V | 21 | |||
| Input low Switching Threshold (USBDP, USBDM) | Vil | 0.8 | V | 21 | |||
| Input High Switching Threshold (USBDP, USBDM) | Vih | 2 | V | 21 | |||
| Frequency of Operation | 11.98 | 12 | 12.02 | MHz | see Note 1 | 21 | |
| Clock Period | 83.19 | 83.33 | 83.47 | ns | 21 | ||
| Duty Cycle | 45 | 50 | 55 | % | 21 | ||
| Switching Threshold (VCCIO=3.3V) | Vt | 1.49 | V | LVTTL | 18 | ||
| Switching Threshold (VCCIO=2.5V) | Vt | 1.1 | V | LVTTL | 19 | ||
| Switching Threshold (VCCIO=1.8V) | Vt | 0.77 | V | LVTTL | 20 |
Materials and finish
As the datasheet states them (page.json metadata.appearance; the 3D model's colours follow it).
| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| housing | Abs | ESD Human Body Mode (HDM) 2000 V Class 2 Table 5.1 Absolute Maximum Ratings | 16 |
CAD (KiCad official)
- Symbol:
FT231XQ-T - Footprint:
Package_DFN_QFN:QFN-20-1EP_4x4mm_P0.5mm_EP2.5x2.5mm - 3D model: QFN-20-EP(4x4) (KiCad packages3D, STEP)
- 3D model files:
ft231xq-t-etched.step/ft231xq-t-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);ft231xq-t.step/ft231xq-t.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: FTDI datasheet (44 pp, sha256
8999a05c9ad906a0, retrieved 2026-10-28, tier: lcsc) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-haiku-5-5(text), consensusclaude-sonnet-5-5(agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish. - CAD: KiCad official libraries (CC-BY-SA 4.0).
# FT231XQ-T
**FTDI** · USB ICs · QFN-20-EP(4x4)
FT231XQ-T from FTDI, in a QFN-20-EP(4x4). Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
## Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | RXD | input | Receiving asynchronous data input. |
| 2 | RI# | input | Ring Indicator input for remote wake up. |
| 3 | GND | power_in | 0V ground input. |
| 4 | DSR# | input | Data Set Ready control input / handshake signal. |
| 5 | DCD# | input | Data Carrier Detect control input. |
| 6 | CTS# | input | Clear To Send control input / handshake signal. |
| 7 | CBUS2 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is TXLED#. |
| 8 | USBDP | bidirectional | USB Data Signal Plus. |
| 9 | USBDM | bidirectional | USB Data Signal Minus. |
| 10 | 3V3OUT | power_out | 3V3 output at 50mA that may be used to power VCCIO; when VCC is 3V3 this pin is an input and should be connected to pin 12. |
| 11 | RESET# | input | Reset input (active low). |
| 12 | VCC | power_in | 5 V or 3V3 supply to the IC; if VCC is 3V3 then 3V3OUT must also be driven with 3V3. |
| 13 | GND | power_in | 0V ground input. |
| 14 | CBUS1 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is RXLED#. |
| 15 | CBUS0 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is TXDEN. |
| 16 | CBUS3 | bidirectional | Configurable CBUS I/O pin whose function is set in the MTP memory; default configuration is SLEEP#. |
| 17 | TXD | output | Transmit asynchronous data output. |
| 18 | DTR# | output | Data Terminal Ready control output / handshake signal. |
| 19 | RTS# | output | Request to Send control output / handshake signal. |
| 20 | VCCIO | power_in | 1V8 to 3V3 supply for the IO cells. |
| 21 | GND | power_in | Exposed pad under the centre of the package, to be connected to GND. |
## Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | FTDI |
| Package | QFN-20-EP(4x4) |
| Category | Interface ICs |
| Pins | 21 |
## Electrical characteristics
Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Storage Temperature | | -65 | | 150 | °C | | 16 |
| Ambient Operating Temperature (Power Applied) | | -40 | | 85 | °C | Power Applied | 16 |
| VCC Supply Voltage | VCC | -0.3 | | 5.5 | V | | 16 |
| VCCIO IO Voltage | VCCIO | -0.3 | | 4 | V | | 16 |
| DC Input Voltage, USBDP and USBDM | | -0.5 | | 3.63 | V | | 16 |
| DC Input Voltage, High Impedance Bi-directionals | | -0.3 | | 5.8 | V | powered from VCCIO | 16 |
| DC Output Current, Outputs | | | | 22 | mA | | 16 |
| VCC Operating Supply Voltage | VCC | 2.97 | 5 | 5.5 | V | Normal Operation | 17 |
| VCCIO Operating Supply Voltage | VCCIO | 1.62 | | 3.63 | V | | 17 |
| Operating Supply Current | Icc1 | 8 | 8 | 8.4 | mA | Normal Operation | 17 |
| Operating Supply Current (USB Suspend) | Icc2 | | 125 | | μA | USB Suspend | 17 |
| 3.3v regulator output | 3V3 | 2.97 | 3.3 | 3.63 | V | VCC must be greater than 3V3 otherwise 3V3OUT is an input which must be driven with 3.3V | 17 |
| Output Voltage High (VCCIO=3.3V) | Voh | 2.97 | | | V | Ioh = +/-2mA; I/O Drive strength = 4mA | 18 |
| Output Voltage Low (VCCIO=3.3V) | Vol | 0 | | 0.4 | V | Iol = +/-2mA; I/O Drive strength = 4mA | 18 |
| Input low Switching Threshold (VCCIO=3.3V) | Vil | | | 0.8 | V | LVTTL | 18 |
| Input High Switching Threshold (VCCIO=3.3V) | Vih | 2 | | | V | LVTTL | 18 |
| Input pull-up resistance (VCCIO=3.3V) | Rpu | 40 | 75 | 190 | KΩ | Vin = 0 | 18 |
| Input pull-down resistance (VCCIO=3.3V) | Rpd | 40 | 75 | 190 | KΩ | Vin =VCCIO | 18 |
| Input Leakage Current (VCCIO=3.3V) | Iin | -10 | 1 | 10 | μA | Vin = 0 | 18 |
| Tri-state output leakage current (VCCIO=3.3V) | Ioz | -10 | 1 | 10 | μA | Vin = 5.5V or 0 | 18 |
| Output Voltage High (VCCIO=2.5V) | Voh | 2.25 | | | V | Ioh = +/-2mA; I/O Drive strength = 4mA | 19 |
| Output Voltage Low (VCCIO=2.5V) | Vol | 0 | | 0.4 | V | Iol = +/-2mA; I/O Drive strength = 4mA | 19 |
| Input low Switching Threshold (VCCIO=2.5V) | Vil | | | 0.8 | V | LVTTL | 19 |
| Input High Switching Threshold (VCCIO=2.5V) | Vih | 0.8 | | | V | LVTTL | 19 |
| Input pull-up resistance (VCCIO=2.5V) | Rpu | 40 | 75 | 190 | KΩ | Vin = 0 | 19 |
| Input pull-down resistance (VCCIO=2.5V) | Rpd | 40 | 75 | 190 | KΩ | Vin =VCCIO | 19 |
| Input Leakage Current (VCCIO=2.5V) | Iin | -10 | 1 | 10 | μA | Vin = 0 | 19 |
| Tri-state output leakage current (VCCIO=2.5V) | Ioz | -10 | 1 | 10 | μA | Vin = 5.5V or 0 | 19 |
| Output Voltage High (VCCIO=1.8V) | Voh | 1.62 | | | V | Ioh = +/-2mA; I/O Drive strength = 4mA | 20 |
| Output Voltage Low (VCCIO=1.8V) | Vol | 0 | | 0.4 | V | Iol = +/-2mA; I/O Drive strength = 4mA | 20 |
| Input low Switching Threshold (VCCIO=1.8V) | Vil | | | 0.77 | V | LVTTL | 20 |
| Input High Switching Threshold (VCCIO=1.8V) | Vih | 1.6 | | | V | LVTTL | 20 |
| Input pull-up resistance (VCCIO=1.8V) | Rpu | 40 | 75 | 190 | KΩ | Vin = 0 | 20 |
| Input pull-down resistance (VCCIO=1.8V) | Rpd | 40 | 75 | 190 | KΩ | Vin =VCCIO | 20 |
| Input Leakage Current (VCCIO=1.8V) | Iin | -10 | 1 | 10 | μA | Vin = 0 | 20 |
| Tri-state output leakage current (VCCIO=1.8V) | Ioz | -10 | 1 | 10 | μA | Vin = 5.5V or 0 | 20 |
| Output Voltage Low (USBDP, USBDM) | Vol | | | 0.2 | V | | 21 |
| Input low Switching Threshold (USBDP, USBDM) | Vil | | | 0.8 | V | | 21 |
| Input High Switching Threshold (USBDP, USBDM) | Vih | 2 | | | V | | 21 |
| Frequency of Operation | | 11.98 | 12 | 12.02 | MHz | see Note 1 | 21 |
| Clock Period | | 83.19 | 83.33 | 83.47 | ns | | 21 |
| Duty Cycle | | 45 | 50 | 55 | % | | 21 |
| Switching Threshold (VCCIO=3.3V) | Vt | | 1.49 | | V | LVTTL | 18 |
| Switching Threshold (VCCIO=2.5V) | Vt | | 1.1 | | V | LVTTL | 19 |
| Switching Threshold (VCCIO=1.8V) | Vt | | 0.77 | | V | LVTTL | 20 |
## Materials and finish
As the datasheet states them (page.json `metadata.appearance`; the 3D model's colours follow it).
| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| housing | Abs | | ESD Human Body Mode (HDM) 2000 V Class 2 Table 5.1 Absolute Maximum Ratings | 16 |
## CAD (KiCad official)
- Symbol: `FT231XQ-T`
- Footprint: `Package_DFN_QFN:QFN-20-1EP_4x4mm_P0.5mm_EP2.5x2.5mm`
- 3D model: QFN-20-EP(4x4) (KiCad packages3D, STEP)
- 3D model files: `ft231xq-t-etched.step` / `ft231xq-t-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ft231xq-t.step` / `ft231xq-t.glb` are the bare package body.
## Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- **Datasheet:** [FTDI datasheet](docs/ft231xq-t-datasheet.pdf) (44 pp, sha256 `8999a05c9ad906a0`, retrieved 2026-10-28, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).
[Datasheet PDF](docs/ft231xq-t-datasheet.pdf)