Datasheet

It has a Li-Po charging circuit that allows the Arduino MKR WIFI 1010 to run on
battery power or an external 5 volt source, charging the Li-Po battery while
running on external power. Switching from one source to the other is done
automatically.
Warning: Unlike most Arduino boards, the MKR WIFI 1010 runs at 3.3V.
The maximum voltage that the I/O pins can tolerate is 3.3V. Applying voltages
higher than 3.3V to any I/O pin could damage the board. While output to 5V
digital devices is possible, bidirectional communication with 5V devices needs
proper level shifting
Microcontroller SAMD21 Cortex-M0+ 32bit Low Power ARM MCU
Board Power Supply (USB/VIN) 5V
Supported Battery(*) Li-Po Single Cell, 3.7V, 700mAh Minimum
Circuit Operating Voltage 3.3V
Digital I/O Pins 8
PWM Pins
12 (0, 1, 2, 3, 4, 5, 6, 7, 8, 10, A3 - or 18 -, A4 -
or 19)
UART 1
SPI 1
I2C 1
I2S 1
Connectivity WiFi
Analog Input Pins 7 (ADC 8/10/12 bit)
Analog Output Pins 1 (DAC 10 bit)
External Interrupts 8 (0, 1, 4, 5, 6, 7, 8, A1 -or 16-, A2 - or 17)
DC Current per I/O Pin 7 mA
Flash Memory 256 KB
SRAM 32 KB
EEPROM No
Clock Speed 32.768 kHz (RTC), 48 MHz
LED_BUILTIN 6
Full-Speed USB Device and Embedded
Host
Included
LED_BUILTIN 6
Length 61.5 mm
Width 25 mm
Weight 32 gr.