This document describes the features and characteristics of a high-performance, low-power AVR 8-bit microcontroller, including advanced RISC architecture, non-volatile program and data memories, peripheral features, special microcontroller features, and I/O and packages.
The ATtiny25/45/85 is a low‑power CMOS 8‑bit microcontroller based on Atmel's enhanced RISC AVR architecture. It offers 2/4/8 KB of flash, up to 512 B of EEPROM, 512 B of SRAM, six programmable I/O lines, a 10‑bit ADC, and multiple timer/counter modules, making it suitable for compact, power‑sensitive designs.
This handbook details the device's features, pin‑out diagrams for PDIP, SOIC and QFN/MLF packages, CPU core architecture, register set, and programming guidelines. It also includes code examples, resource links, and reliability information such as data‑retention and endurance specifications.
| Operating Voltage | 1.8 – 5.5 V (ATtiny25/45/85V) / 2.7 – 5.5 V (ATtiny25/45/85) |
|---|---|
| Flash Memory | 2 KB / 4 KB / 8 KB |
| EEPROM | 128 B / 256 B / 512 B |
| EEPROM Endurance | 100,000 write/erase cycles |
| SRAM | 128 B / 256 B / 512 B |
| Programmable I/O Lines | 6 |
| Timer/Counter | 8‑bit Timer/Counter with Prescaler and Two PWM Channels |
| ADC | 10‑bit |
| Package Types | 8‑pin PDIP, 8‑pin SOIC, 20‑pad QFN/MLF |
| Speed Grade | 0‑4 MHz @1.8‑5.5 V, 0‑10 MHz @2.7‑5.5 V (ATtiny25/45/85V) |
The device operates from 1.8 V to 5.5 V for the ATtiny25/45/85V version and from 2.7 V to 5.5 V for the ATtiny25/45/85 version.
The microcontroller provides 2 KB, 4 KB, or 8 KB of in‑system programmable flash memory.
The EEPROM can endure up to 100,000 write/erase cycles.
The device is available in 8‑pin PDIP, 8‑pin SOIC, and 20‑pad QFN/MLF packages.