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ATSAMD21J18A

Microcontroller

The ATSAMD21J18A is a microcontroller from Microchip Technology. View the full ATSAMD21J18A datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

Official ATSAMD21J18A datasheet (PDF) — the source this page was extracted from.

ATSAMD21J18A Key Specifications

ParameterValue
ConnectivityI2C, LINbus, SPI, UART/USART, USB
Core ProcessorARM® Cortex®-M0+
Core Size32-Bit
Data ConvertersA/D 20x12b; D/A 1x10b
DigiKey ProgrammableNot Verified
Mounting TypeSurface Mount
Number of I/O52
Operating Temperature-40°C ~ 85°C (TA)
Oscillator TypeInternal
Package / Case64-TQFP
PackagingTray
PeripheralsBrown-out Detect/Reset, DMA, I2S, POR, PWM, WDT
Flash Memory Size256KB (256K x 8)
Program Memory TypeFLASH
RAM Size32K x 8 B
Clock Speed48MHz
Standard Pack Qty160
Supplier Device Package64-TQFP (10x10)
Supply Voltage1.62V ~ 3.6V

ATSAMD21J18A Overview

Part: ATSAMD21J18A-AU — Microchip (Atmel)

Type: ARM Cortex-M0+ MCU

Description: 32-bit ARM Cortex-M0+ MCU running at up to 48 MHz with up to 256 KB Flash and 32 KB SRAM, 1.62–3.63 V operation, USB, 6 SERCOMs, 12-bit ADC and 10-bit DAC.

Operating Conditions:

  • Supply voltage: 1.62–3.63 V
  • Operating temperature: -40 to 125 °C (AEC-Q100 Grade 1)
  • Max CPU clock: 48 MHz

Absolute Maximum Ratings:

  • Max supply voltage (VDD): 3.8 V
  • Max current into a VDD pin: 92 mA
  • Max current out of a GND pin: 130 mA
  • Pin voltage: GND-0.6 V to VDD+0.6 V
  • Storage temperature: -60 to 150 °C

Key Specs:

  • CPU: ARM Cortex-M0+ up to 48 MHz with single-cycle hardware multiplier
  • Memory: 32/64/128/256 KB Flash, 4/8/16/32 KB SRAM
  • ADC: 12-bit, 350 ksps, up to 20 channels, 1/2x to 16x gain stage
  • DAC: 10-bit, 350 ksps
  • USB: full-speed 12 Mbps USB 2.0, host and device, eight endpoints
  • Serial: up to six SERCOMs (USART, I²C up to 3.4 MHz, SPI, LIN slave), one I²S interface
  • I/O: up to 52 programmable I/O pins
  • Timers: up to five 16-bit TC and up to four 24-bit TCC

Features:

  • 12-channel DMA controller and 12-channel event system
  • 48 MHz DFLL and 48–96 MHz fractional DPLL
  • Idle and Stand-by sleep modes with SleepWalking peripherals
  • Power-on Reset and Brown-out Detection
  • 256-channel Peripheral Touch Controller for capacitive touch
  • Up to four analog comparators with window compare
  • 32-bit RTC with clock/calendar, watchdog timer, CRC-32 generator
  • Serial Wire Debug and Micro Trace Buffer
  • Drop-in compatible with SAM D20
  • AEC-Q100 Grade 1 qualified

Applications:

  • Capacitive touch and proximity sensing
  • PWM and motor control
  • USB-connected embedded systems
  • Automotive (AEC-Q100 Grade 1)

Package:

  • 64-pin TQFP, QFN, UFBGA
  • 48-pin TQFP, QFN
  • 45-pin WLCSP
  • 35-pin WLCSP
  • 32-pin TQFP, QFN

ATSAMD21J18A Features

  • Processor

  • -ARM ® Cortex ® -M0+ CPU running at up to 48 MHz

  • Single-cycle hardware multiplier

  • Micro Trace Buffer (MTB)

  • Memories

  • -32/64/128/256 KB in-system self-programmable Flash

  • -4/8/16/32 KB SRAM Memory

  • System

  • -Power-on Reset (POR) and Brown-out Detection (BOD)

  • -Internal and external clock options with 48 MHz Digital Frequency-Locked Loop (DFLL48M) and 48 MHz to 96 MHz Fractional Digital Phase-Locked Loop (FDPLL96M)

  • -External Interrupt Controller (EIC)

  • -16 external interrupts

  • -One Non-maskable Interrupt (NMI)

  • -Two-pin Serial Wire Debug (SWD) programming, test and debugging interface

  • Low Power

  • -Idle and Stand-by Sleep modes

  • -SleepWalking peripherals

  • Peripherals

  • -12-channel Direct Memory Access Controller (DMAC)

  • -12-channel Event System

  • -Up to five 16-bit Timer/Counters (TC), configurable as either:

  • One 16-bit TC with two compare/capture channels

  • One 8-bit TC with two compare/capture channels

  • One 32-bit TC with two compare/capture channels, by using two TCs

  • -Up to four 24-bit Timer/Counters for Control (TCC), with extended functions:

  • Up to four compare channels with optional complementary output

  • Generation of synchronized pulse width modulation (PWM) pattern across port pins

  • Deterministic fault protection, fast decay and configurable dead-time between complementary output

  • Dithering that increase resolution with up to 5 bit and reduce quantization error

  • -32-bit Real Time Counter (RTC) with clock/calendar function

  • -Watchdog Timer (WDT)

  • -CRC-32 generator

  • -One full-speed (12 Mbps) Universal Serial Bus (USB) 2.0 interface

  • Embedded host and device function

  • Eight endpoints

  • -Up to six Serial Communication Interfaces (SERCOM), each configurable to operate as either:

  • USART with full-duplex and single-wire half-duplex configuration

  • I 2 C up to 3.4 MHz

  • SPI

  • LIN slave

  • -One two-channel Inter-IC Sound (I 2 S) interface

  • -One 12-bit, 350ksps Analog-to-Digital Converter (ADC) with up to 20 channels

  • Differential and single-ended input

  • 1/2x to 16x programmable gain stage

  • Automatic offset and gain error compensation

  • Oversampling and decimation in hardware to support 13-, 14-, 15- or 16-bit resolution

  • -10-bit, 350 ksps Digital-to-Analog Converter (DAC)

  • -Up to four Analog Comparators (AC) with Window Compare function

  • -Peripheral Touch Controller (PTC)

  • 256-Channel capacitive touch and proximity sensing

  • I/O

  • -Up to 52 programmable I/O pins

  • Qualification

  • -AEC-Q100 Grade 1 (-40°C to 125°C)

  • Drop-in compatible with SAM D20

  • Packages

  • -64-pin TQFP, QFN, UFBGA

  • -48-pin TQFP, QFN

  • -45-pin WLCSP

  • -35-pin WLCSP

  • -32-pin TQFP, QFN

  • Operating Voltage

  • -1.62V - 3.63V

ATSAMD21J18A Applications

Updated description in 31.6.1 Principle of Operation.

Updated description in sub sections of 31.6.2 Basic Operation.

Updated description in sub sections of 31.6.3 Additional Features.

Updated description in 31.6.6 Synchronization.

Lock Update (LUPD) bit description updated in Control B Clear (CTRLBCLR) register.

Compare Channel Buffer x Busy (CCBx) bit description updated in Synchronization Busy (SYNCBUSY) register.

Event Control (EVCTRL) register property updated: Removed Enable-Protected.

Interrupt Enable Clear (INTENCLR), Interrupt Enable Set (INTENSET) and Interrupt Flag Status and Clear (INTFLAG) registers: Updated bit description of FAULT0, FAULT1, FAULTA and FAULTB.

STATUS register bit descriptions updated.

Wave Control (WAVE) register property updated: Removed Read-Synchronized.

Pattern Buffer (PATTB) register: Updated property and bit description.

Waveform Control Buffer (WAVEB) register: Updated property and bit descriptions.

ATSAMD21J18A Pin Configuration

The Pin Configuration register (PINCFGy) is used for additional I/O pin configuration. A pin can be set in a totem-pole or pull configuration.

As pull configuration is done through the Pin Configuration register, all intermediate PORT states during switching of pin direction and pin values are avoided.

The I/O pin configurations are described further in this chapter, and summarized in Table 23-2.

ATSAMD21J18A Electrical Characteristics

...........continuedMax.Units
f GCLK_EVSYS_CHANNEL_8EVSYS channel 8 input clock frequency48MHz
f GCLK_EVSYS_CHANNEL_9EVSYS channel 9 input clock frequency48MHz
f GCLK_EVSYS_CHANNEL_10EVSYS channel 10 input clock frequency48MHz
f GCLK_EVSYS_CHANNEL_11EVSYS channel 11 input clock frequency48MHz
f GCLK_SERCOMx_SLOWCommon SERCOM slow input clock frequency48MHz
f GCLK_SERCOM0_CORESERCOM0 input clock frequency48MHz
f GCLK_SERCOM1_CORESERCOM1 input clock frequency48MHz
f GCLK_SERCOM2_CORESERCOM2 input clock frequency48MHz
f GCLK_SERCOM3_CORESERCOM3 input clock frequency48MHz
f GCLK_SERCOM4_CORESERCOM4 input clock frequency48MHz
f GCLK_SERCOM5_CORESERCOM5 input clock frequency48MHz
f GCLK_TCC0 , f GCLK_TCC1TCC0, TCC1 input clock frequency96MHz
f GCLK_TCC2 , f GCLK_TCC3 , f GCLK_TC3TCC2, TCC3, TC3 input clock frequency96MHz
f GCLK_TC4 , f GCLK_TC5TC4, TC5 input clock frequency48MHz
f GCLK_TC6 , f GCLK_TC7TC6, TC7 input clock frequency48MHz
f GCLK_ADCADC input clock frequency48MHz
f GCLK_AC_DIGAC digital input clock frequency48MHz
f GCLK_AC_ANAAC analog input clock frequency64KHz
f GCLK_AC1_DIGAC1 digital input clock frequency48MHz
f GCLK_AC1_ANAAC1 analog input clock frequency64KHz
f GCLK_DACDAC input clock frequency350KHz
f GCLK_PTCPTC input clock frequency48MHz
f GCLK_I2S_0I2S serial 0 input clock frequency13MHz
f GCLK_I2S_1I2S serial 1 input clock frequency13MHz

ATSAMD21J18A Absolute Maximum Ratings

Stresses beyond those listed in this section may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

Table 37-2. Absolute Maximum Ratings

SymbolDescriptionMin.Max.Units
V DDPower supply voltage03.8V
I VDDCurrent into a V DD pin-92 (1)mA
I GNDCurrent out of a GND pin-130 (1)mA
V PINPin voltage with respect to GND and V DDGND-0.6VV DD +0.6VV
T storageStorage temperature-60150°C
  1. Maximum source current is 46mA and maximum sink current is 65mA per cluster. A cluster is a group of GPIOs as shown in the table below. Also note that each VDD/GND pair is connected to two clusters so current consumption through the pair will be a sum of the clusters source/sink currents.

CAUTION

This device is sensitive to electrostatic discharges (ESD). Improper handling may lead to permanent performance degradation or malfunctioning.

Handle the device following best practice ESD protection rules: Be aware that the human body can accumulate charges large enough to impair functionality or destroy the device.

CAUTION

In debugger cold-plugging mode, NVM erase operations are not protected by the BOD33 and BOD12. NVM erase operation at supply voltages below specified minimum can cause corruption of NVM areas that are mandatory for correct device behavior.

7.2.4 GPIO Clusters

ATSAMD21J18A Thermal Information

The following Table summarizes the thermal resistance data depending on the package.

Table 37-1. Thermal Resistance Data

Package Typeθ JAθ JC
32-pin TQFP64.7°C/W23.1°C/W
48-pin TQFP63.6°C/W12.2°C/W
64-pin TQFP60.9°C/W12.2°C/W
32-pin QFN40.9°C/W15.2°C/W
48-pin QFN32.0°C/W10.9°C/W
64-pin QFN32.5°C/W10.7°C/W
35-ball WLCSP41.8°C/W2.26°C/W
45-ball WLCSP43.97°C/W2.91°C/W
64-pin UFBGA53°C/W4.74°C/W

ATSAMD21J18A Package Information

Note: For current package drawings, refer to the Microchip Packaging Specification, which is available at http://www.microchip.com/packaging.

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part NumberManufacturerPackage
ATSAMD21Microchip Technology—
ATSAMD21E18A-AUMicrochip Technology32-TQFP
ATSAMD21J18A-AUMicrochip Technology64-TQFP

More part numbers on this datasheet

Their pages show this same datasheet. Some are linked through their part family rather than checked part by part, so confirm the exact part in the ordering information.

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