2.1 Common Peripherals
The following table shows the list of peripherals that are present in both families:
| Peripherals/Features | ATmega16 | ATmega32 | ATmega64 | ATmega128 | AVR® DA Family | AVR® DB Family | 
|---|---|---|---|---|---|---|
| Maximum Frequency | 16 MHz (VDD ≥ 4.5V) | 16 MHz (VDD ≥ 4.5V) | 16 MHz (VDD ≥ 4.5V) | 16 MHz (VDD ≥ 4.5V) | 24 MHz | 24 MHz | 
| Supply voltage (VDD) | 1.8–5.5V | 1.8–5.5V | 1.8–5.5V | 1.8–5.5V | 1.8–5.5V | 1.8–5.5V | 
| Package (pin number) | 40, 44 | 40, 44 | 64 | 64 | 28, 32, 48, 64 | 28, 32, 48, 64 | 
| 
                             Flash memory 
 (Read-while-write section)  | 
                             16 KB 
 (14 KB)  | 
                             32 KB 
 (28 KB)  | 
                             64 KB 
 (56 KB)  | 
                             128 KB 
 (120 KB)  | 
                             32-128 KB 
 -  | 
                             32-128 KB 
 -  | 
| RAM memory | 1 KB | 2 KB | 4 KB | 4 KB | 4-16 KB | 4-16 KB | 
| EEPROM | 512 bytes | 1 KB | 2 KB | 4 KB | 512 bytes | 512 bytes | 
| GPIO | 32 | 32 | 53 | 53 | 51 | 51 | 
| USART | 1 | 1 | 2 | 2 | 5 | 5 | 
| SPI | 1 | 1 | 1 | 1 | 2 | 2 | 
| TWI (I2C) | 1 | 1 | 1 | 1 | 2 | 2 | 
| 8-bit Timer/Counter | 2 | 2 | 2 | 2 | -(1) | -(1) | 
| 12-bit Timer/Counter | - | - | - | - | 1 | 1 | 
| 16-bit Timer/Counter | 1 | 1 | 1 | 1 | 7(1) | 7(1) | 
| Real Time Counter (RTC) | 1 | 1 | 1 | 1 | 1 | 1 | 
| Analog Comparator (AC) | 1 | 1 | 1 | 1 | 3 | 3 | 
| Analog-to-Digital Converter (ADC) | 1 | 1 | 1 | 1 | 1 | 1 | 
| Watchdog Timer (WDT) | 1 | 1 | 1 | 1 | 1 | 1 | 
Note: 
            
- For AVR Dx, each TCA in the Split mode works as two separate 8-bit timers, each of them having three compare channels for PWM generation.
 
