Mechanical Dimensions & Land Pattern (WLCSP-64(3.1x3.1))
Extracted from Datasheet & IPC-7351B NormalizedRecommended Companion BOM & Drop-In Equivalents
Passive external components per reference schematic and 1:1 pin-compatible alternatives| Designator / Replacement MPN | Value / Package | Function & PCB Layout Rule |
|---|---|---|
| N/A BOM | Per application circuit WLCSP-64(3.1x3.1) | Size power & signal trace widths for rated load current following IPC-2221 clearance rules. |
Technical Frequently Asked Questions (FAQ) — STM32L431RBY6TR (WLCSP-64(3.1x3.1))
Quick answers covering Pinout, IPC-7351B Land Pattern dimensions, and CAD export formatsWhat is the Pinout and operating voltage specification of STM32L431RBY6TR (WLCSP-64(3.1x3.1))?
Manufactured by ST, the STM32L431RBY6TR is housed in a WLCSP-64(3.1x3.1) package with 64 pins and a 0.35 mm lead pitch, supporting a VCC supply range of 1.71 V to 3.6 V. Key pins include: A1 (VDD: Power Supply Input (VDD — 3.3V VDD (Max 4.0V))), A2 (PA15 (JTDI): Multiplexed I/O & Peripheral Pin PA15 (JTDI) (UART, SPI, SWD/JTAG)), A3 (PC12: Multiplexed I/O & Peripheral Pin PC12 (UART, SPI)), A4 (PD2: Multiplexed I/O & Peripheral Pin PD2 (UART)), A5 (PB3 (JTDO - TRACE SWO): Multiplexed I/O & Peripheral Pin PB3 (JTDO - TRACE SWO) (UART, SPI, PWM, SWD/JTAG)), A6 (PB7: Multiplexed I/O & Peripheral Pin PB7 (UART)).
What are the IPC-7351B PCB Footprint dimensions for STM32L431RBY6TR?
Normalized from the official datasheet mechanical drawing per IPC-7351B (Density Level B Nominal), STM32L431RBY6TR (WLCSP-64(3.1x3.1)) has a nominal body envelope of 3.10 × 3.10 mm, pitch e = 0.35 mm, and 64 copper pads.
Where can I download KiCad (.kicad_mod, .kicad_sym), Fusion 360 (.lbr), and 3D STEP models for STM32L431RBY6TR?
You can download the verified open-hardware (CERN-OHL-P-2.0) CAD library bundle for STM32L431RBY6TR (ST, WLCSP-64(3.1x3.1)) directly on this page, including KiCad 8 Footprints (.kicad_mod), Schematic Symbols (.kicad_sym), Autodesk Fusion 360 / Eagle (.lbr), and 3D STEP AP214 / WebGL GLB models.
Static Reference Appendix: Pinout Table (64 pins) & STM32L431 Family VariantsExpand static table
| Pin # | Signal Name | Electrical Type | Functional Description & Design Notes |
|---|---|---|---|
| A1 | VDD | Power_In | Primary positive power supply input (VDD) operating in the 3.3V VDD (Max 4.0V) domain (Max rating: 4.0V). |
| A2 | PA15 (JTDI) | Digital_IO | Signal terminal PA15 (JTDI) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI1_NSSSPI3NSS. Supported peripheral buses: UART, SPI, SWD/JTAG. |
| A3 | PC12 | Digital_IO | Signal terminal PC12 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI3_MOSI. Supported peripheral buses: UART, SPI. |
| A4 | PD2 | Digital_IO | Signal terminal PD2 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PD2. Supported peripheral buses: UART. |
| A5 | PB3 (JTDO - TRACE SWO) | Digital_IO | Signal terminal PB3 (JTDO - TRACE SWO) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI3_SCK. Supported peripheral buses: UART, SPI, PWM, SWD/JTAG. |
| A6 | PB7 | Digital_IO | Signal terminal PB7 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PB7. Supported peripheral buses: UART. |
| A7 | VSS | GND | 0V electrical ground return terminal (VSS) for internal core logic, I/O drivers, and analog sub-blocks. |
| A8 | VDD | Power_In | Primary positive power supply input (VDD) operating in the 3.3V VDD (Max 4.0V) domain (Max rating: 4.0V). |
| B1 | VSS | GND | 0V electrical ground return terminal (VSS) for internal core logic, I/O drivers, and analog sub-blocks. |
| B2 | PA14 (JTCK - SWCLK) | Digital_IO | Signal terminal PA14 (JTCK - SWCLK) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: I2C1_SMBA. Supported peripheral buses: I2C, SWD/JTAG. |
| B3 | PC11 | Digital_IO | Signal terminal PC11 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI3_MISO. Supported peripheral buses: UART, SPI. |
| B4 | PB4 (NJTRST) | Digital_IO | Signal terminal PB4 (NJTRST) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: I2C3_SDA, SPI1_MISOSPI3MISO. Supported peripheral buses: UART, SPI, I2C, SWD/JTAG. |
| B5 | PB6 | Digital_IO | Signal terminal PB6 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PB6. Supported peripheral buses: UART. |
| B6 | PB9 | Digital_IO | Signal terminal PB9 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI2_NSSCAN1TX. Supported peripheral buses: SPI. |
| B7 | VBAT | Power_In | Primary positive power supply input (VBAT) operating in the 3.3V VDD (Max 4.0V) domain (Max rating: 4.0V). |
| B8 | PC13 | Digital_IO | Signal terminal PC13 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC13. Supported peripheral buses: RTC/CLK. |
| C1 | PA12 | Digital_IO | Signal terminal PA12 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA12. Supported peripheral buses: UART, CAN. |
| C2 | PA13 (JTMS - SWDIO) | Digital_IO | Signal terminal PA13 (JTMS - SWDIO) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA13 (JTMS - SWDIO). Supported peripheral buses: SWD/JTAG. |
| C3 | PC10 | Digital_IO | Signal terminal PC10 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI3_SCKUSART3TX. Supported peripheral buses: SPI. |
| C4 | PB5 | Digital_IO | Signal terminal PB5 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: I2C1_SMBA, SPI1_MOSISPI3MOSI. Supported peripheral buses: UART, SPI, I2C. |
| C5 | PH3/ BOOT0 | Digital_IO | Signal terminal PH3/ BOOT0 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PH3/ BOOT0. Supported peripheral buses: General. |
| C6 | PB8 | Digital_IO | Signal terminal PB8 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PB8. Supported peripheral buses: I2C. |
| C7 | IOC7 | Digital_IO | General Purpose Digital I/O Pin IOC7 |
| C8 | PC14 - OSC32_I N(PC14) | Digital_IO | Signal terminal PC14 - OSC32_I N(PC14) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC14 - OSC32_I N(PC14). Supported peripheral buses: RTC/CLK. |
| D1 | PA9 | Digital_IO | Signal terminal PA9 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA9. Supported peripheral buses: UART, PWM. |
| D2 | PA10 | Digital_IO | Signal terminal PA10 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA10. Supported peripheral buses: UART, I2C, PWM. |
| D3 | PA11 | Digital_IO | Signal terminal PA11 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI1_MISO. Supported peripheral buses: UART, SPI, PWM, CAN. |
| D4 | PC4 | Digital_IO | Signal terminal PC4 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC4. Supported peripheral buses: UART, ADC. |
| D5 | PC0 | Digital_IO | Signal terminal PC0 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC0. Supported peripheral buses: ADC. |
| D6 | NRST | Digital_IO | Active-low hardware reset terminal (NRST): pulling this pin Low resets the processor core and peripherals. |
| D7 | PH1 - OSC_ OUT (PH1) | Digital_IO | Signal terminal PH1 - OSC_ OUT (PH1) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PH1 - OSC_ OUT (PH1). Supported peripheral buses: RTC/CLK. |
| D8 | PH0 - OSC_ IN(PH0) | Digital_IO | Signal terminal PH0 - OSC_ IN(PH0) (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PH0 - OSC_ IN(PH0). Supported peripheral buses: RTC/CLK. |
| E1 | PC7 | Digital_IO | Signal terminal PC7 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC7. Supported peripheral buses: General. |
| E2 | PC9 | Digital_IO | Signal terminal PC9 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC9. Supported peripheral buses: General. |
| E3 | PA8 | Digital_IO | Signal terminal PA8 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA8. Supported peripheral buses: UART, SPI, RTC/CLK. |
| E4 | PC5 | Digital_IO | Signal terminal PC5 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC5. Supported peripheral buses: UART, ADC. |
| E5 | PA4 | Digital_IO | Signal terminal PA4 (I/O, 3.3V VDD (Max 4.0V) domain). Multiplexed alternate functions: SPI1_NSSSPI3NSS. Supported peripheral buses: UART, SPI, ADC, DAC. |
| E6 | PC3 | Digital_IO | Signal terminal PC3 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI2_MOSI_SAI1SDA. Supported peripheral buses: SPI, ADC. |
| E7 | PC2 | Digital_IO | Signal terminal PC2 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI2_MISOEVENTOUT. Supported peripheral buses: SPI, ADC. |
| E8 | PC1 | Digital_IO | Signal terminal PC1 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: I2C3_SDA. Supported peripheral buses: I2C, ADC. |
| F1 | PC6 | Digital_IO | Signal terminal PC6 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC6. Supported peripheral buses: General. |
| F2 | PB15 | Digital_IO | Signal terminal PB15 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI2_MOSI. Supported peripheral buses: SPI, I2C, PWM, RTC/CLK. |
| F3 | PC8 | Digital_IO | Signal terminal PC8 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PC8. Supported peripheral buses: General. |
| F4 | PB0 | Digital_IO | Signal terminal PB0 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PB0. Supported peripheral buses: UART, ADC, PWM. |
| F5 | PA5 | Digital_IO | Signal terminal PA5 (I/O, 3.3V VDD (Max 4.0V) domain). Multiplexed alternate functions: SPI1_SCK. Supported peripheral buses: SPI, ADC, DAC, PWM. |
| F6 | PA2 | Digital_IO | Signal terminal PA2 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA2. Supported peripheral buses: ADC, PWM. |
| F7 | PA0 | Digital_IO | Signal terminal PA0 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA0. Supported peripheral buses: UART, ADC, PWM, RTC/CLK. |
| F8 | VSSA/ VREF - | GND | 0V electrical ground return terminal (VSSA/ VREF -) for internal core logic, I/O drivers, and analog sub-blocks. |
| G1 | PB14 | Digital_IO | Signal terminal PB14 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI2_MISO. Supported peripheral buses: UART, SPI, PWM. |
| G2 | PB13 | Digital_IO | Signal terminal PB13 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI2_SCK. Supported peripheral buses: UART, SPI, PWM. |
| G3 | PB12 | Digital_IO | Signal terminal PB12 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PB12. Supported peripheral buses: UART, I2C. |
| G4 | PB2 | Digital_IO | Signal terminal PB2 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: I2C3_SMBAEVENTOUT. Supported peripheral buses: I2C, RTC/CLK. |
| G5 | PA6 | Digital_IO | Signal terminal PA6 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PA6. Supported peripheral buses: UART, ADC. |
| G6 | PA3 | Digital_IO | Signal terminal PA3 (I/O, 3.3V VDD (Max 4.0V) domain). Multiplexed alternate functions: PA3. Supported peripheral buses: ADC, PWM. |
| G7 | PA1 | Digital_IO | Signal terminal PA1 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI1_SCK. Supported peripheral buses: UART, SPI, ADC, PWM. |
| G8 | VDDA/ VREF+ | Power_In | Primary positive power supply input (VDDA/ VREF+) operating in the 3.3V VDD (Max 4.0V) domain (Max rating: 4.0V). |
| H1 | VDD | Power_In | Primary positive power supply input (VDD) operating in the 3.3V VDD (Max 4.0V) domain (Max rating: 4.0V). |
| H2 | VSS | GND | 0V electrical ground return terminal (VSS) for internal core logic, I/O drivers, and analog sub-blocks. |
| H3 | PB11 | Digital_IO | Signal terminal PB11 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PB11. Supported peripheral buses: UART, PWM. |
| H4 | PB10 | Digital_IO | Signal terminal PB10 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI2_SCKUSART3TX. Supported peripheral buses: SPI, PWM. |
| H5 | PB1 | Digital_IO | Signal terminal PB1 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: PB1. Supported peripheral buses: UART, ADC, PWM. |
| H6 | PA7 | Digital_IO | Signal terminal PA7 (I/O, 3.3V VDD (5V-Tolerant FT) domain). Multiplexed alternate functions: SPI1_MOSI. Supported peripheral buses: SPI, ADC, PWM. |
| H7 | VDD | Power_In | Primary positive power supply input (VDD) operating in the 3.3V VDD (Max 4.0V) domain (Max rating: 4.0V). |
| H8 | VSS | GND | 0V electrical ground return terminal (VSS) for internal core logic, I/O drivers, and analog sub-blocks. |












