STM32L011F4P6 from STMicroelectronics, in a TSSOP-20. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	PB9/BOOT0	input	Boot-mode select input (B-type). After reset acts as BOOT0; system boots from user Flash, system memory, or SRAM depending on BOOT0 level sampled at reset. Also available as PB9 GPIO after reset if BOOT0 remapped via option bytes.
2	PC14-OSC32_IN	bidirectional	5V-tolerant I/O (FT). Additional function: LSE 32.768 kHz crystal oscillator input (OSC32_IN). Doubles as PC14 GPIO when LSE not used.
3	PC15-OSC32_OUT	bidirectional	Standard 3.3 V I/O (TC). Additional function: LSE 32.768 kHz crystal oscillator output (OSC32_OUT). Doubles as PC15 GPIO when LSE not used.
4	NRST	bidirectional	Device reset input, active low, with internal weak pull-up (RST type). Also driven low internally to signal an internal reset source. Pull externally low >20 us to force reset.
5	VDDA	power_in	Analog supply for ADC, comparators, reset block, PLL, and internal voltage reference. Must equal or exceed VDD; range 1.65 V-3.6 V. Decouple to VSS with 100 nF + 1 uF close to the pin.
6	PA0-CK_IN	bidirectional	3.3 V ADC-tolerant I/O (TTa). Alt functions: USART2_RX/CTS, LPTIM1_IN1, TIM2_CH1/ETR, LPUART1_RX, COMP1_OUT. Additional: COMP1_INM, ADC_IN0, RTC_TAMP2/WKUP1, CK_IN (external clock in).
7	PA1	bidirectional	5V-tolerant I/O (FT). Alt functions: EVENTOUT, LPTIM1_IN2, TIM2_CH2, I2C1_SMBA, USART2_RTS, TIM21_ETR, LPUART1_TX. Additional: COMP1_INP, ADC_IN1.
8	PA2	bidirectional	3.3 V ADC-tolerant I/O (TTa). Alt functions: TIM21_CH1, TIM2_CH3, USART2_TX, LPUART1_TX, COMP2_OUT. Additional: COMP2_INM, ADC_IN2, RTC_TAMP3/RTC_TS/RTC_OUT/WKUP3.
9	PA3	bidirectional	5V-tolerant I/O (FT). Alt functions: TIM21_CH2, TIM2_CH4, USART2_RX, LPUART1_RX. Additional: COMP2_INP, ADC_IN3.
10	PA4	bidirectional	3.3 V ADC-tolerant I/O (TTa). Alt functions: SPI1_NSS, LPTIM1_IN1/ETR, I2C1_SCL, USART2_CK, TIM2_ETR, LPUART1_TX, COMP2_OUT. Additional: COMP1_INM, COMP2_INM, ADC_IN4.
11	PA5	bidirectional	3.3 V ADC-tolerant I/O (TTa). Alt functions: SPI1_SCK, LPTIM1_IN2, TIM2_ETR, TIM2_CH1. Additional: COMP1_INM, COMP2_INM, ADC_IN5.
12	PA6	bidirectional	5V-tolerant I/O (FT). Alt functions: SPI1_MISO, LPTIM1_ETR, LPUART1_CTS, EVENTOUT, COMP1_OUT. Additional: ADC_IN6.
13	PA7	bidirectional	5V-tolerant I/O (FT). Alt functions: SPI1_MOSI, LPTIM1_OUT, USART2_CTS, TIM21_ETR, EVENTOUT, COMP2_OUT. Additional: COMP2_INP, ADC_IN7.
14	PB1	bidirectional	5V-tolerant I/O (FT). Alt functions: USART2_CK, SPI1_MOSI, LPTIM1_IN1, LPUART1_RTS, TIM2_CH4. Additional: ADC_IN9, VREF_OUT.
15	VSS	power_in	Digital and analog ground reference (0 V). Tie to system ground plane; footnote 5 confirms this pin serves both digital and analog return.
16	VDD	power_in	Main digital supply, 1.65 V-3.6 V. Powers I/Os and internal regulator. Decouple to VSS with 100 nF close to the pin.
17	PA9	bidirectional	5V-tolerant Fm+ I/O (FTf). Alt functions: MCO clock output, I2C1_SCL, LPTIM1_OUT, USART2_TX, TIM21_CH2, COMP1_OUT.
18	PA10	bidirectional	5V-tolerant Fm+ I/O (FTf). Alt functions: TIM21_CH1, I2C1_SDA, RTC_REFIN, USART2_RX, TIM2_CH3, COMP1_OUT.
19	PA13	bidirectional	5V-tolerant Fm+ I/O (FTf). Default after reset: SWDIO (serial-wire debug data). Alt functions: SWDIO, LPTIM1_ETR, I2C1_SDA, SPI1_SCK, LPUART1_RX, COMP1_OUT.
20	PA14	bidirectional	5V-tolerant I/O (FT). Default after reset: SWCLK (serial-wire debug clock). Alt functions: SWCLK, LPTIM1_OUT, I2C1_SMBA, USART2_TX, SPI1_MISO, LPUART1_TX, COMP2_OUT.

Key specifications

Parameter	Value
Manufacturer	STMicroelectronics
Package	TSSOP-20
Category	MCU
Pins	20

Ordering variants

Same part, different packaging or reel option.

STM32L011F4P6
STM32L011F4P6F3P6
STM32L011F4P6G4U6
STM32L011F4P6G3U6
STM32L011F4P6D4P6
STM32L011F4P6D3P6
STM32L011F4P6E4U6
STM32L011F4P6E3U6
STM32L011F4P6K4U6
STM32L011F4P6K3U6
STM32L011F4P6K4T6
STM32L011F4P6K3T6
STM32L011F4P6E4Y6
STM32L011F4P6E3Y6

CAD (KiCad official)

Symbol: STM32L011F4P6
Footprint: Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm
3D model: TSSOP-20 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`stm32l011f4p6.step`	267 KB	You want the bare part, or you mark your own boards.
`stm32l011f4p6-etched.step`	3.0 MB	You want the part with `STM32L011F4P6` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 765 faces against 327 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: STMicroelectronics datasheet (115 pp, sha256 d598d4dcb828e7dc, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF