| Specifications | ATtiny427 | ATtiny827 | ATtiny1627 | ATtiny3227 |
|---|---|---|---|---|
| Flash (program memory) | 4096 bytes | 8192 bytes | 16384 bytes | 32768 bytes |
| Flash w/Optiboot | 3584 bytes | 7680 bytes | 15872 bytes | 32256 bytes |
| RAM | 512 bytes | 1024 bytes | 2048 bytes | 3072 bytes |
| EEPROM | 128 bytes | 128 bytes | 256 bytes | 256 bytes |
| Bootloader | Optiboot (optional, not recommended) | Optiboot (optional) | Optiboot (optional) | Optiboot (optional) |
| GPIO Pins | 22 (21 usable) | 22 (21 usable) | 22 (21 usable) | 22 (21 usable) |
| ADC Channels | 12 (11 usable) | 12 (11 usable) | 12 (11 usable) | 12 (11 usable) |
| DAC | Yes | Yes | Yes | Yes |
| PWM Channels | 8 | 8 | 8 | 8 |
| Timer Type B | 2 | 2 | 2 | 2 |
| Timer Type D | No | No | No | No |
| Interfaces | UART (2), SPI, I2C | UART (2), SPI, I2C | UART (2), SPI, I2C | UART (2), SPI, I2C |
| Clock options | Internal 20/16/10/8/5/4/1 MHz | Internal 20/16/10/8/5/4/1 MHz | Internal 20/16/10/8/5/4/1 MHz | Internal 20/16/10/8/5/4/1 MHz |
TBD