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ATSAML21J18B-UUT

Microcontroller

The ATSAML21J18B-UUT is a microcontroller from Microchip Technology. View the full ATSAML21J18B-UUT datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

ATSAML21J18B-UUT shares its datasheet with ATSAML21J18B-AUT, whose page lists every part number it covers.

Official ATSAML21J18B-UUT datasheet (PDF) — the source this page was extracted from.

Package

WLCSP-64

ATSAML21J18B-UUT Key Specifications

ParameterValue
ConnectivityI2C, LINbus, SCI, SPI, UART/USART, USB
Core ProcessorARM® Cortex®-M0+
Core Size32-Bit
Data ConvertersA/D 20x12b; D/A 2x12b
DigiKey ProgrammableNot Verified
Mounting TypeSurface Mount
Number of I/O51
Operating Temperature-40°C ~ 85°C (TA)
Oscillator TypeInternal
Package / Case64-TQFP
PackagingMouseReel
PeripheralsDMA, POR, PWM, WDT
Flash Memory Size256KB (256K x 8)
Program Memory TypeFLASH
RAM Size32K x 8 B
Clock Speed48MHz
Standard Pack Qty1500
Supplier Device Package64-TQFP (10x10)
Supply Voltage1.62V ~ 3.63V

ATSAML21J18B-UUT Overview

Part: ATSAML21J18B-AUT — Microchip (Atmel) SAM L21J

Type: ARM Cortex-M0+ Ultra Low-Power MCU

Description: 32-bit Arm Cortex-M0+ MCU at up to 48 MHz with up to 256 KB Flash and 40 KB SRAM, 1.62–3.63 V operation, in 64-pin packages.

Operating Conditions:

  • Supply voltage: 1.62–3.63 V
  • Operating temperature: -40 to 85 °C (suffix-dependent; -40 to 105 °C also listed for other grades)
  • Max CPU clock: 48 MHz

Absolute Maximum Ratings:

  • Max supply voltage (VDD): 3.8 V
  • Max current into a VDD pin: 92 mA (max source 46 mA / sink 65 mA per GPIO cluster)
  • 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 (2.46 CoreMark/MHz)
  • Memory: 32/64/128/256 KB Flash; 4/8/16/32 KB SRAM main plus 2/4/8/8 KB low-power SRAM
  • ADC: 12-bit, 1 MSPS, up to 20 channels
  • DAC: two 12-bit, 1 MSPS dual-output
  • USB: full-speed 12 Mbps USB 2.0 host/device
  • SERCOM: up to six, each configurable as USART, I2C (up to 3.4 MHz), SPI or LIN slave
  • I/O: up to 51 programmable pins
  • Touch: PTC with 169-channel capacitive touch and proximity sensing

Features:

  • Idle, Stand-by, Backup and Off sleep modes with SleepWalking peripherals
  • Static and dynamic power gating, battery backup support
  • Embedded Buck/LDO regulator with on-the-fly selection
  • Two performance levels
  • 16-channel DMAC and 12-channel Event System
  • Up to five 16-bit TCs and three TCCs (two 24-bit, one 16-bit)
  • AES engine, TRNG, CRC-32, Configurable Custom Logic
  • Three op-amps, two analog comparators
  • Oscillators: XOSC, XOSC32K, OSC16M, DFLL48M, FDPLL96M
  • Serial Wire Debug and Micro Trace Buffer
  • 32-bit RTC with clock/calendar and watchdog timer

Applications:

  • Ultra low-power battery-powered devices
  • Capacitive touch and proximity sensing interfaces

Package:

  • 64-pin TQFP, QFN, WLCSP (SAM L21J)
  • Other family members: 48-pin TQFP/QFN, 32-pin TQFP/QFN

ATSAML21J18B-UUT Features

  • Processor
  • -Arm Cortex-M0+ CPU running at up to 48 MHz
  • Single-cycle hardware multiplier
  • Micro Trace Buffer
  • Memories
  • -32/64/128/256-KB in-system self-programmable Flash
  • -1/2/4/8-KB Flash Read-While-Write section
  • -4/8/16/32-KB SRAM main memory
  • -2/4/8/8-KB SRAM low-power memory
  • System
  • -Power-on Reset (POR) and Brown-out Detection (BOD)
  • -Internal and external clock options
  • -External Interrupt Controller (EIC)
  • -16 external interrupts
  • -One non-maskable interrupt
  • -Two-pin Serial Wire Debug (SWD) programming, testing, and debugging interface
  • Low Power
  • -Idle, Stand-by, Backup, and Off Sleep modes
  • -SleepWalking peripherals
  • -Static and Dynamic Power Gating Architecture
  • -Battery backup support
  • -Two performance levels
  • -Embedded Buck/LDO regulator supporting on-the-fly selection
  • Peripherals
  • -16-channel Direct Memory Access Controller (DMAC)
  • -12-channel Event System
  • -Up to five 16-bit Timer/Counters (TC) including one low-power TC, each configurable as:
  • 16-bit TC with two compare/capture channels
  • 8-bit TC with two compare/capture channels
  • 32-bit TC with two compare/capture channels, by using two TCs

ATSAML21J18B-UUT Pin Configuration

The Pin Configuration register (PINCFGy) is used for additional I/O pin configuration. A pin can be set in a totempole, 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 29-2.

ATSAML21J18B-UUT Electrical Characteristics

SymbolParametersConditionsMin.Typ.Max.Unit
Gain accuracy16X Gain---1.43%
4X Gain--+-0.4
1X Gain--+/-0.25
THDTotal Harmonic Distortion @10kHz - mode 316X Gain--77-dB
4X Gain--72.8-
1X Gain--82.6-
Integrated Noise, BW=[0.1Hz-10 kHz], 16X gain - VOUT=1VMode 3-147-μVrms
Mode 2-147-
Mode 1-162-
Mode 0-191-
...........continued - Symbol...........continued - Parameters...........continued - Conditions...........continued - Min............continued - Typ............continued - Max............continued - Unit
Integrated Noise, BW=[0.1Hz-1MHz], 16X gain - VOUT=1VMode 3-262-μVrms
Mode 2-247-
Mode 1-235-
Mode 0-235-

Note: 1.These values are based on simulation. They are not covered by production test limits or characterization.

ATSAML21J18B-UUT Absolute Maximum Ratings

Stresses beyond those listed in Table 46-1 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 46-1. 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-0.6VVDD+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.

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.

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.

ATSAML21J18B-UUT Thermal Information

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

Table 50-1. Thermal Resistance Data

Package Typeθ JAθ JC
Dummy valuedummy valuedummy value

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
ATSAML21Microchip Technology—
ATSAML21EMicrochip Technology—
ATSAML21GMicrochip Technology—
ATSAML21JMicrochip Technology—
ATSAML21J18B-ANTMicrochip Technology—
ATSAML21J18B-AUTMicrochip Technology64-TQFP
ATSAML21J18B-AUT-SLLMicrochip TechnologyTQFP-64
ATSAML21J18B-MNTMicrochip TechnologyQFN-64
ATSAML21J18B-MUTMicrochip TechnologyQFN-64
ATSAML21J18B-MUT-SLLMicrochip TechnologyQFN-64

Other Microcontrollers (MCU)

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Data on this page is extracted from publicly available manufacturer datasheets using automated tools including AI. It may contain errors or omissions. Always verify specifications against the official manufacturer datasheet before making design or purchasing decisions. See our Terms of Service. Rights holders can submit a takedown request.

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