PIC12F1840-I from Microchip, in a SOIC-8. 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	VDD	power_in	Positive supply for logic and I/O pins. 2.3V-5.5V for PIC12F1840, 1.8V-3.6V for PIC12LF1840. Bypass with 0.1 µF ceramic capacitor.
2	RA5	bidirectional	General purpose I/O port bit 5. Alternate functions: SRNQ (SR latch Q-not), T1CKI/T1OSI (Timer1 clock in / oscillator in), CCP1/P1A (via APFCON), RX/DT (EUSART receive/data via APFCON), IOC (interrupt-on-change), programmable weak pull-up, OSC1/CLKIN (external oscillator input).
3	RA4	bidirectional	General purpose I/O port bit 4. Alternate functions: AN3 (ADC channel 3), CPS3 (cap sense 3), C1IN1- (comparator negative input), T1G/T1OSO (Timer1 gate / oscillator out), P1B (ECCP via APFCON), TX/CK (EUSART transmit/clock via APFCON), SDO (MSSP data out via APFCON), IOC, MDCIN2 (modulator carrier), pull-up, OSC2/CLKOUT/CLKR.
4	MCLR/VPP/RA3	input	Master Clear (Reset) input, active low; also programming voltage (VPP) input during ICSP; can be configured as input-only RA3 via configuration word. Also provides T1G (Timer1 gate alt), SS (MSSP slave select), IOC, and pull-up. Input-only pin.
5	RA2	bidirectional	General purpose I/O port bit 2. Alternate functions: AN2 (ADC channel 2), CPS2 (cap sense 2), C1OUT (comparator output), SRQ (SR latch Q), T0CKI (Timer0 clock in), CCP1/P1A/FLT0 (ECCP), SDA/SDI (MSSP I2C data / SPI data in), INT/IOC, MDCIN1, pull-up.
6	RA1/ICSPCLK	bidirectional	General purpose I/O port bit 1; also ICSP programming clock (ICSPCLK / ICPCLK). Alternate functions: AN1 (ADC channel 1), VREF (external reference), CPS1 (cap sense 1), C1IN0- (comparator negative input), SRI (SR latch reset), RX/DT (EUSART receive/data), SCL/SCK (MSSP I2C clock / SPI clock), IOC, MDMIN (modulator data), pull-up.
7	RA0/ICSPDAT	bidirectional	General purpose I/O port bit 0; also ICSP programming data (ICSPDAT / ICDDAT). Alternate functions: AN0 (ADC channel 0), DACOUT (DAC output), CPS0 (cap sense 0), C1IN+ (comparator positive input), P1B (ECCP), TX/CK (EUSART transmit/clock), SDO/SS (MSSP SPI data out / slave select), IOC, MDOUT (modulator output), pull-up.
8	VSS	power_in	Ground reference for logic and I/O pins. Connect to system ground.

Key specifications

Parameter	Value
Manufacturer	Microchip
Package	SOIC-8
Category	MCU
Pins	8

Ordering variants

Same part, different packaging or reel option.

PIC12F1840-II/P
PIC12F1840-II/SN
PIC12F1840-II/MF
PIC12F1840-II/MC
PIC12F1840-II/RF

CAD (KiCad official)

Symbol: PIC12F1840-I
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOIC-8 (KiCad packages3D, STEP)

Provenance

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

Datasheet: Microchip datasheet (397 pp, sha256 79e88d8e63728e96, 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