component
ATtiny85
Public Made by Adomby adom
Microchip 8-bit AVR MCU, SOIC-8. 8 KB flash, 512 B EEPROM/SRAM, 6 I/O, 10-bit ADC, up to 20 MHz. Datasheet-verified.
3D Model
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Symbol & Footprint
Schematic Symbol
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PCB Footprint
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Datasheet
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README
markdownATtiny85
Microchip Technology · 8-bit AVR MCU · SOIC-8 (EIAJ 8S2)
8-bit AVR RISC microcontroller in a SOIC-8 (EIAJ 8S2) package, with 8 KB in-system programmable flash, 512 B EEPROM, and 512 B SRAM. Six I/O lines carry a 4-channel 10-bit ADC, two timer/counters with PWM, a USI for I2C/SPI, an analog comparator, and debugWIRE. It runs 2.7-5.5 V up to 20 MHz (1.8-5.5 V to 10 MHz on the V suffix). The default tiny MCU for small embedded tasks. Every pin is multiplexed; consult the pinout for alternate functions.
Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | PB5/PCINT5/RESET/ADC0/dW | bidirectional | Port B bit 5. Multiplexed with active-low external RESET input, PCINT5 pin-change interrupt, ADC channel 0, and debugWIRE (dW) single-wire debug I/O. When the RSTDISBL fuse is programmed, it can serve as a (weak) I/O pin; otherwise it is the reset input. |
| 2 | PB3/PCINT3/XTAL1/CLKI/OC1B̄/ADC3 | bidirectional | Port B bit 3. Multiplexed with XTAL1 crystal oscillator input, external clock input (CLKI), inverted Timer/Counter1 output-compare B (/OC1B), ADC channel 3, and PCINT3 pin-change interrupt. |
| 3 | PB4/PCINT4/XTAL2/CLKO/OC1B/ADC2 | bidirectional | Port B bit 4. Multiplexed with XTAL2 crystal oscillator output, system clock output (CLKO), Timer/Counter1 output-compare B (OC1B), ADC channel 2, and PCINT4 pin-change interrupt. |
| 4 | GND | power_in | Ground reference (0 V). |
| 5 | PB0/MOSI/DI/SDA/AIN0/OC0A/OC1Ā/AREF/PCINT0 | bidirectional | Port B bit 0. Heavily multiplexed: SPI MOSI (programming), USI Data-Input (DI, three-wire) / SDA (I2C two-wire), analog comparator positive input (AIN0), Timer/Counter0 output-compare A (OC0A), inverted Timer/Counter1 output-compare A (/OC1A), external ADC voltage reference (AREF), and PCINT0 pin-change interrupt. |
| 6 | PB1/MISO/DO/AIN1/OC0B/OC1A/PCINT1 | bidirectional | Port B bit 1. Multiplexed with SPI MISO (programming), USI Data-Output (DO, three-wire), analog comparator negative input (AIN1), Timer/Counter0 output-compare B (OC0B), Timer/Counter1 output-compare A (OC1A), and PCINT1 pin-change interrupt. |
| 7 | PB2/SCK/USCK/SCL/ADC1/T0/INT0/PCINT2 | bidirectional | Port B bit 2. Multiplexed with SPI SCK (programming clock), USI clock (USCK three-wire) / SCL (I2C two-wire clock), ADC channel 1, Timer/Counter0 external clock input (T0), external interrupt 0 (INT0), and PCINT2 pin-change interrupt. |
| 8 | VCC | power_in | Supply voltage. 2.7–5.5 V for ATtiny85 (0–20 MHz), 1.8–5.5 V for ATtiny85V (0–10 MHz). Decouple with a 100 nF ceramic close to the pin. |
Key specifications
| Parameter | Value |
|---|---|
| Type | 8-bit AVR RISC microcontroller |
| Flash | 8 KB (in-system programmable) |
| EEPROM | 512 B |
| SRAM | 512 B |
| I/O lines | 6 |
| ADC | 4-channel 10-bit |
| Timers | Two 8-bit with PWM |
| Interfaces | USI (I2C / SPI), debugWIRE |
| Supply / clock | 2.7-5.5 V, 0-20 MHz |
| Package | SOIC-8 (EIAJ 8S2) |
| Body (L×W×H) | 5.3 × 5.3 × 1.75 mm |
Ordering variants
ATtiny85-20SU (SOIC-8, 20 MHz)ATtiny85V-10SU (SOIC-8, 10 MHz, 1.8 V)
CAD (KiCad official)
- Symbol:
MCU_Microchip_ATtiny:ATtiny85-20S - Footprint:
Package_SO:SOIC-8_5.3x5.3mm_P1.27mm - 3D model: SOIC-8 wide / EIAJ (KiCad packages3D)
- 3D model files:
attiny85-etched.step/attiny85-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);attiny85.step/attiny85.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Microchip Technology datasheet (234 pp, sha256
0e3fa6a7d608de9b, retrieved 2026-08-17, tier: manufacturer) - Extractor:
ds2sf(Claude) — every pin and dimension is cited to a datasheet page; refuses to fabricate. - CAD: KiCad official libraries (CC-BY-SA 4.0).