Configuration Summary

  SAM D21J SAM D21G SAM D21E
Pins 64 48 (45 for WLCSP) 32 (35 for WLCSP)
General Purpose I/O-pins (GPIOs) 52 38 26
Flash 256/128/64/32KB 256/128/64/32KB 256/128/64/32KB
SRAM 32/16/8/4KB 32/16/8/4KB 32/16/8/4KB
Timer Counter (TC) instances 5 3 3
Waveform output channels per TC instance 2 2 2
Timer Counter for Control (TCC) instances 3 3 3
Waveform output channels per TCC 8/4/2 8/4/2 8/4/2
DMA channels 12 12 12
USB interface 1 1 1
Serial Communication Interface (SERCOM) instances 6 6 4
Inter-IC Sound (I2S) interface 1 1 1
Analog-to-Digital Converter (ADC) channels 20 14 10
Analog Comparators (AC) 2 2 2
Digital-to-Analog Converter (DAC) channels 1 1 1
Real-Time Counter (RTC) Yes Yes Yes
RTC alarms 1 1 1
RTC compare values

One 32-bit value or

two 16-bit values

One 32-bit value or

two 16-bit values

One 32-bit value or

two 16-bit values

External Interrupt lines 16 16 16
Peripheral Touch Controller (PTC) X and Y lines

16x16

12x10

10x6

Maximum CPU frequency 48MHz
Packages

QFN

TQFP

UFBGA

QFN

TQFP

WLCSP

QFN

TQFP

WLCSP

Oscillators

32.768kHz crystal oscillator (XOSC32K)

0.4-32MHz crystal oscillator (XOSC)

32.768kHz internal oscillator (OSC32K)

32KHz ultra-low-power internal oscillator (OSCULP32K)

8MHz high-accuracy internal oscillator (OSC8M)

48MHz Digital Frequency Locked Loop (DFLL48M)

96MHz Fractional Digital Phased Locked Loop (FDPLL96M)

Event System channels 12 12 12
SW Debug Interface Yes Yes Yes
Watchdog Timer (WDT) Yes Yes Yes