FT232BL - USB UART IC, USB 2.0 Full-Speed, LQFP-32 | FTDI
Référence : FT232BL ✗ Fin de vie| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $5.18 | $5,18 |
| 10 | $4.62 | $46,20 |
| 100 | $4.05 | $405,00 |
| 500 | $3.55 | $1 775,00 |
| 1 000 | $3.1 | $3 100,00 |
FT232BL Présentation
A USB UART bridge is a class of interface IC that handles the USB protocol stack on one side and presents a classical asynchronous serial (UART) interface on the other. It belongs to the broader USB-to-peripheral bridge category, sitting between USB controllers and simpler serial devices. USB UART bridges are essential when a host MCU or legacy equipment lacks native USB but needs to exchange bytes with a PC. In the component taxonomy, the FT232BL is an Interface IC > USB Bridge > USB-to-UART converter.
Key features of the FT232BL include a 3 Mbaud maximum UART baud rate, integrated 3.3V LDO, full USB 2.0 full-speed compliance, six CBUS-configurable pins, hardware flow control on modem signals, and optional external 93C46/93C56/93C66 EEPROM support. The device integrates a clock multiplier PLL, eliminating the need for an external 48 MHz source. USB suspend and resume are handled in hardware, drawing less than 500 uA suspend current for battery-powered designs.
The FT232BL architecture consists of an 8051-compatible USB protocol engine, FIFO controllers, UART engine, and a parallel CBUS configuration block. The 8051 core executes FTDI's firmware from internal ROM, which is why the part requires no external flash. Data flows from USB endpoint buffers through 384-byte TX and 128-byte RX FIFOs into the UART block. The 6 MHz external crystal is multiplied internally by an 8x PLL to generate 48 MHz for the USB block.
Typical applications include microcontroller-to-PC serial bridges (Arduino-compatible boards, STM32 Nucleo, ESP32 debug logs), industrial RS-232/RS-422 adapters, USB programmer/debugger interfaces (JTAG/SPI bridges), barcode scanner interfaces, GPS module USB dongles, and legacy equipment modernization. The wide OS driver support makes the FT232BL a low-risk choice for cross-platform products.
When designing, observe USB-IF signal-integrity guidelines: keep the D+/D- traces 90 ohm differential, length-matched within 2 mm, and route over a continuous ground plane. Add a ferrite bead on VBUS if the design is bus-powered and may be hot-plugged.
This page synthesizes distributor pricing, drop-in and migration alternatives, and practical design notes not collected in the manufacturer datasheet alone, supporting faster sourcing decisions for engineers.
Alternatives de remplacement direct pour FT232BL — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
FT232BM
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
FT232BL Spécifications
| Manufacturer | FTDI (Future Technology Devices International Ltd.) |
| Part Number | FT232BL |
| Fonction | USB to UART interface bridge IC |
| USB Standard | USB 2.0 Full-Speed (12 Mbps) |
| UART Data Rate | 300 baud to 3 Mbaud |
| Supply Voltage (VCC) | 4.35 V to 5.25 V |
| Supply Current (Operating) | 25 mA typical |
| Internal 3.3V LDO Output | 3.3 V, up to 50 mA |
| External Crystal Frequency | 6 MHz (fundamental, parallel resonant) |
| Internal Clock | 48 MHz via on-chip 8x PLL |
| UART Signals | TXD, RXD, RTS#, CTS#, DTR#, DSR#, DCD#, RI# |
| CBUS Pins | 6 configurable (CBUS0 to CBUS5) |
| EEPROM Interface | 93C46 / 93C56 / 93C66 (optional) |
| Boîtier | LQFP-32 (7 x 7 mm, 0.8 mm pitch) |
| Température de fonctionnement | -40 C to +85 C |
| Type de montage | Surface Mount |
| Statut RoHS | Compliant |
| USB-IF Compliance | Yes (USB 2.0 Full-Speed certified) |
Configuration des broches de FT232BL
| Broche 1 | GND — Ground reference |
| Broche 2 | VCC — 5V supply input (4.35V to 5.25V) |
| Broche 3 | VCC — 5V supply input (tied to pin 2) |
| Broche 4 | VCC — 5V supply input |
| Broche 5 | VCC — 5V supply input |
| Broche 6 | 3V3OUT — 3.3V LDO output (up to 50 mA) |
| Broche 7 | RESET# — External reset input (active low) |
| Broche 8 | TEST — Test pin - tie to GND per datasheet |
| Broche 9 | CBUS0 — Configurable CBUS pin 0 (EEPROM-programmable) |
| Broche 10 | CBUS1 — Configurable CBUS pin 1 |
| Broche 11 | CBUS2 — Configurable CBUS pin 2 |
| Broche 12 | CBUS3 — Configurable CBUS pin 3 |
| Broche 13 | CBUS4 — Configurable CBUS pin 4 |
| Broche 14 | CBUS5 — Configurable CBUS pin 5 |
| Broche 15 | NC — Not connected (per datasheet) |
| Broche 16 | USBDP — USB D+ data line |
| Broche 17 | USBDM — USB D- data line |
| Broche 18 | TXD — UART transmit output |
| Broche 19 | RXD — UART receive input |
| Broche 20 | RTS# — Ready To Send (active low) |
| Broche 21 | CTS# — Clear To Send (active low) |
| Broche 22 | DTR# — Data Terminal Ready (active low) |
| Broche 23 | DSR# — Data Set Ready (active low) |
| Broche 24 | DCD# — Data Carrier Detect (active low) |
| Broche 25 | RI# — Ring Indicator (active low) |
| Broche 26 | EECS — EEPROM chip select |
| Broche 27 | XTIN — 6 MHz crystal input |
| Broche 28 | XTOUT — 6 MHz crystal output |
| Broche 29 | EEDATA — EEPROM data I/O |
| Broche 30 | EECLK — EEPROM clock output |
| Broche 31 | NC — Not connected (per datasheet) |
| Broche 32 | GND — Ground reference |
Applications typiques
FT232BL convient pour 6 applications: Microcontroller USB Debug Bridge, Industrial RS-232 / RS-422 Converter, USB Programmer / Debugger Interface, Barcode Scanner / POS Terminal Interface, GPS / GNSS USB Dongle Interface, Legacy Equipment Modernization Adapter.
Microcontroller USB Debug Bridge
The FT232BL fits USB-to-UART debug logging for microcontrollers (Arduino, STM32, ESP32) because of its 3 Mbaud UART ceiling and USB 2.0 Full-Speed (12 Mbps) throughput. Engineers typically wire TXD/RXD to the MCU UART pins and use the CBUS0/CBUS1 pins configured as TXLED/RXLED to drive status LEDs. The integrated 3.3V LDO at pin 6 (50 mA) can power a small MCU rail directly, eliminating an external regulator. Compared to the FT232RL, the FT232BL adds BOM (crystal, EEPROM) but offers configurable CBUS pin assignment via EEPROM, which is useful when the MCU board needs unique USB VID/PID identifiers.
Recommandé
Industrial RS-232 / RS-422 Converter
The FT232BL is widely deployed in industrial USB-to-RS-232/RS-422 adapters because of its full modem-control signal set (RTS#/CTS#/DTR#/DSR#/DCD#/RI#) and 3 Mbaud data rate. A MAX232 or MAX3232 level translator downstream of the FT232BL converts the UART CMOS levels to RS-232 +-5V/-7V levels for legacy PLCs, lab instruments, and CNC controllers. The FT232BL's 5V VCC (4.35V to 5.25V) lets the converter board share a single 5V rail, and the operating temperature range of -40 C to +85 C supports factory-floor deployment. Compared to isolated USB-UART ICs, the FT232BL requires external isolation for medical or process-control applications.
Recommandé
USB Programmer / Debugger Interface
The FT232BL serves as the USB-to-serial backbone of many in-circuit programmers, JTAG/SPI debug probes, and bit-bang tool interfaces. With CBUS pins configurable as GPIO via EEPROM, the FT232BL can bit-bang JTAG TMS/TCK/TDO/TDI, providing a low-cost JTAG programmer solution. The 3 Mbaud UART ceiling allows fast flash programming, and the wide host-OS support (Windows, macOS, Linux) makes it a universal development tool. The EEPROM-programmable VID/PID prevents driver collision with other FTDI parts on the same host.
Recommandé
Barcode Scanner / POS Terminal Interface
The FT232BL is found in USB barcode scanners, receipt printers, and POS terminals because of its reliable USB 2.0 Full-Speed compliance and hardware flow control. The hardware RTS#/CTS# handshake prevents data loss during bursty barcode scans, and the integrated LDO powers the scanner's logic rail. Compared to the CP2102, the FT232BL has the advantage of FTDI's mature VCP/D2XX driver ecosystem, which offers robust latency control for time-sensitive peripherals. The 6 MHz crystal requirement adds BOM cost versus crystal-less alternatives but ensures deterministic USB timing.
Recommandé
GPS / GNSS USB Dongle Interface
The FT232BL integrates into USB GPS dongles where the FT232BL converts between USB host and the GPS module's UART NMEA stream. The FT232BL's 3 Mbaud UART supports GPS modules running at 115.2 kbaud to 921.6 kbaud NMEA output without bottleneck. The hardware flow control pins prevent NMEA sentence drops when the host is busy. Compared to the CH340 used in low-cost GPS dongles, the FT232BL provides better driver support on Linux (no proprietary VID/PID issues) and more reliable suspend/resume behavior for laptop power management.
Recommandé
Legacy Equipment Modernization Adapter
The FT232BL is commonly used to modernize legacy RS-232 equipment by adding USB connectivity without redesigning the host MCU firmware. Engineers connect the FT232BL's UART pins to the legacy equipment's serial port, then attach a 93C46 EEPROM to customize VID/PID and product strings. The FT232BL's drivers enumerate the legacy device as a virtual COM port (VCP), preserving backward compatibility with legacy host software. Compared to newer FT-X series ICs, the FT232BL has the advantage of mature OS support and a stable driver base going back to Windows XP.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour FT232BL — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | FT232BQ | FT232BM | FT232BQ-REEL |
|---|---|---|---|---|
| Brand | FTDI | FTDI | FTDI | FTDI |
| Package | LQFP-32 (7x7 mm) | QFN-32 (5x5 mm) - different | LQFP-32 (7x7 mm) - same | QFN-32 (5x5 mm) - different |
| USB Standard | USB 2.0 Full-Speed (12 Mbps) | USB 2.0 Full-Speed (12 Mbps) | USB 2.0 Full-Speed (12 Mbps) | USB 2.0 Full-Speed (12 Mbps) |
| UART Baud Rate | 300 to 3 Mbaud | 300 to 3 Mbaud | 300 to 3 Mbaud | 300 to 3 Mbaud |
| Internal 3.3V LDO | Yes (50 mA) | Yes (50 mA) | Yes (50 mA) | Yes (50 mA) |
| External Crystal Required | Yes (6 MHz) | Yes (6 MHz) | Yes (6 MHz) | Yes (6 MHz) |
| CBUS Pins | 6 configurable | 6 configurable | 6 configurable | 6 configurable |
| Lifecycle Status | NRND | NRND | NRND (older) | NRND |
Principaux différenciateurs
- Integrated 3.3V LDO with 50 mA output for MCU rail (vs FT232RL)
- 6 configurable CBUS pins via external EEPROM (vs FT232BM)
- LQFP-32 7x7 mm package for hand-solderability (vs FT232BQ)
Notes de conception
Route USB D+ (pin 16) and D- (pin 17) as a 90 ohm differential pair with intra-pair length mismatch less than 2 mm. Maintain a continuous ground reference under the pair and avoid crossing any other high-speed traces or power planes. Place the USB connector within 50 mm of the FT232BL to minimize stub reflections. The 6 MHz crystal traces (XTIN/XTOUT) should be short, symmetric, and isolated from the USB pair to prevent clock harmonics from coupling into USB signaling.
Bulk-decouple VCC (pins 2-5) with a 4.7 uF X5R ceramic plus a 0.1 uF X7R ceramic placed within 3 mm of the supply pins. The integrated 3.3V LDO output at pin 6 must be decoupled with a minimum 1 uF X5R ceramic; this rail can supply up to 50 mA to external logic. If the design is bus-powered from VBUS, add a ferrite bead on VCC to suppress bus-rail noise. Verify total system power budget stays under 500 mA for USB 2.0 compliance when bus-powered.
Do NOT tie pin 8 (TEST) high or leave it floating; the FTDI datasheet requires TEST be tied to GND for normal operation. Skipping the external EEPROM (93C46/93C56/93C66) causes the FT232BL to use FTDI's default VID/PID (0403:6001), which may conflict if multiple FT232BL boards are attached to the same host. For unique VID/PID, populate the EEPROM or accept the FTDI default. Resistors on CBUS pins should be sized to limit sink current to 4 mA per pin per the datasheet.
Informations de conformité
RoHS compliant per FTDI product page. The FT232BL is NRND (Not Recommended for New Designs) per FTDI lifecycle; production designs should target FT232RL or FT-X series. AEC-Q100 not applicable since this is an interface IC for industrial/consumer/commercial environments, not automotive-grade.