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Home Products Integrated Circuits (ICs)Embedded - Microcontrollers~~ATMEGA164P-20AUR~~

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ATMEGA164P-20AUR - Microchip Technology

Name: Microchip Technology ATMEGA164P-20AUR
Brand: Microchip Technology
SKU: ATMEGA164P-20AUR
Price: 1.878 USD
Availability: InStock
Rating: 5 (7 reviews)

Manufacturer Part Number: ATMEGA164P-20AUR

Manufacturer: Microchip Technology

Allelco Part Number: 32D-ATMEGA164P-20AUR

Warranty: 1 Year Allelco Warranty - Find out more

Stock Status:: 8,980 pcs available, New & Original

Parts Description: IC MCU 8BIT 16KB FLASH 44TQFP

Package: 44-TQFP (10x10)

Data sheet: ATMEGA164P-20AU.pdf

Datasheets
ATmega164_324_644P/V Appendix.pdf

PCN Design/Specification
ATMEGA Datasheet 12/Dec/2018.pdf Marking Chgs 11/Jul/2017.pdf

HTML Datasheet
Cylindrical Battery Holders.pdf

PCN Packaging
Boxes 07/Dec/2016.pdf Transfer to Microchip/Label/Pkg 5/Sep/2016.pdf

PCN Other
2.73KHz.pdf

RoHs Status: ROHS3 Compliant

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In stock: 8980

Unit Price: $2.815
Subtotal: $0.00

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Quantity	Unit Price	Ext. Price
1+	$2.815	$2.82
10+	$2.454	$24.54
30+	$2.24	$67.20
100+	$2.023	$202.30
500+	$1.923	$961.50
1000+	$1.878	$1,878.00

The above prices does not include taxes and freight rates, which will be calculated on the order pages.

Specifications

ATMEGA164P-20AUR Tech Specifications
Microchip Technology - ATMEGA164P-20AUR technical specifications, attributes, parameters and parts with similar specifications to Microchip Technology - ATMEGA164P-20AUR

Product Attribute	Attribute Value
Manufacturer	Microchip Technology
Voltage - Supply (Vcc/Vdd)	2.7V ~ 5.5V
Supplier Device Package	44-TQFP (10x10)
Speed	20MHz
Series	AVR® ATmega
RAM Size	1K x 8
Program Memory Type	FLASH
Program Memory Size	16KB (8K x 16)
Peripherals	Brown-out Detect/Reset, POR, PWM, WDT
Package / Case	44-TQFP
Package	Tape & Reel (TR)

Product Attribute	Attribute Value
Oscillator Type	Internal
Operating Temperature	-40°C ~ 85°C (TA)
Number of I/O	32
Mounting Type	Surface Mount
EEPROM Size	512 x 8
Data Converters	A/D 8x10b
Core Size	8-Bit
Core Processor	AVR
Connectivity	I²C, SPI, UART/USART
Base Product Number	ATMEGA164

Environmental & Export Classifications

ATTRIBUTE	DESCRIPTION
RoHs Status	ROHS3 Compliant
Moisture Sensitivity Level (MSL)	3 (168 Hours)
REACH Status	REACH Unaffected
ECCN	EAR99
HTSUS	8542.31.0001

Parts Introduction

ATMEGA164P-20AUR (1)

Manufacturer Part Number

ATMEGA164P-20AUR

Manufacturer

Microchip Technology

Introduction

Advanced 8-bit AVR microcontroller with multiple communication interfaces

Product Features and Performance

8-bit AVR core processor

Operating speed up to 20MHz

I2C, SPI, and UART/USART serial communication

32 programmable I/O lines

16KB FLASH program memory

512 bytes EEPROM

1KB internal SRAM

Product Advantages

High integration for peripheral control

Low power consumption

Robust serial communication options

Flexible and easy to program

Key Technical Parameters

Clock Speed: 20MHz

Program Memory: 16KB FLASH

EEPROM Size: 512 bytes

RAM Size: 1KB

Number of I/O pins: 32

Voltage Range: 2.7V to 5.5V

Analog to Digital Converter: 8 channels, 10-bit resolution

Temperature Range: -40°C to 85°C

Quality and Safety Features

Brown-out Detect/Reset

Power-on Reset

Programmable Watchdog Timer

Compatibility

Compatible with a wide range of supply voltages

44-pin TQFP surface mount package

Application Areas

Industrial control systems

Automotive systems

Consumer electronics

Internet of Things devices

Product Lifecycle

Currently active

Not near discontinuation

Upgrade and replacement options available

Several Key Reasons to Choose This Product

Long-term availability and support

Large set of integrated peripherals reducing BOM costs

Good community and documentation for development

Broad operational temperature range suitable for industrial applications

Proven track record of reliability in various applications

Frequently Asked Questions(FAQ)

How does the operating voltage range of ATMEGA164P-20AUR influence power supply design in battery-operated embedded systems?: The ATMEGA164P-20AUR supports a wide supply voltage range from 2.7V to 5.5V, which allows flexible integration into systems powered by single-cell lithium batteries or regulated 3.3V/5V rails. This enables direct operation from sources like Li-ion (3.0–4.2V) without requiring additional step-up regulators, reducing component count and system complexity. Designers can leverage the full dynamic range to optimize power consumption—lower voltages reduce active and sleep-mode current draw, extending battery life in portable devices.

What trade-offs should be considered when selecting between internal oscillator modes for the ATMEGA164P-20AUR?: The ATMEGA164P-20AUR features an internal calibrated RC oscillator capable of running at 1MHz, 2MHz, 4MHz, or 8MHz, with a factory-trimmed accuracy typically within ±1% to ±10%, depending on temperature and voltage. While this eliminates the need for external crystals, it introduces variability in timing-critical applications such as UART baud rate generation or PWM frequency stability. For precise timing requirements exceeding ±2%, an external crystal oscillator is recommended, despite increased PCB footprint and cost.

Can the ATMEGA164P-20AUR reliably operate in industrial environments with temperature fluctuations?: Yes, the ATMEGA164P-20AUR is specified for operation from -40°C to +85°C, making it suitable for industrial control systems exposed to ambient thermal variations. However, performance near the extremes may affect oscillator accuracy and I/O leakage currents. In high-reliability designs, margin testing under actual operating temperatures is advised to validate communication protocols and peripheral timing.

How does the memory architecture of ATMEGA164P-20AUR impact firmware development workflows?: With 16KB of Flash program memory, 1KB of SRAM, and 512 bytes of EEPROM, the ATMEGA164P-20AUR supports typical embedded applications but imposes constraints on code size and data persistence. Developers must carefully manage stack usage due to limited RAM, and EEPROM writes should be minimized because each byte can endure only about 100,000 write cycles. Code optimization and static variable allocation are essential to prevent runtime crashes.

What are the implications of using the ATMEGA164P-20AUR’s ADC module in signal acquisition circuits?: The integrated 10-bit successive approximation ADC provides eight multiplexed channels with a conversion time of approximately 13 ADC clock cycles. When sampling analog signals, designers must ensure proper settling time before conversion and use an appropriate reference voltage—either Vcc, AREF pin, or internal 1.1V bandgap. Sampling rates above 100 ksps may require careful layout to avoid noise coupling into sensitive input paths.

How does pin count and package choice affect PCB routing complexity when using the ATMEGA164P-20AUR?: The 44-pin TQFP (10x10mm) package offers 32 general-purpose I/O pins, enabling moderate complexity in board design but demanding attention to trace spacing and grounding. Due to its compact form factor, simultaneous switching noise can couple between adjacent pins if not decoupled properly. Decoupling capacitors near Vcc/GND pairs and careful placement of bypass capacitors are necessary to maintain stable operation at 20MHz.

In what scenarios would replacing ATMEGA164P-20AUR with a lower-power variant make sense?: If an application runs on coin cells or ultra-low-power sensors where average current below 10µA in sleep mode is critical, a variant like ATMEGA164PA-20AU might offer improved power management features such as enhanced sleep modes or reduced leakage. However, the standard ATMEGA164P-20AUR already includes Brown-out Detection and Power-on Reset, providing adequate protection without significant power overhead.

What factors determine whether to use SPI or I2C peripherals on the ATMEGA164P-20AUR?: SPI offers higher throughput (up to 20MHz with external clock) and full-duplex communication, ideal for flash memory or display interfaces. I2C supports multi-master configurations over longer traces and uses fewer wires, beneficial for sensor networks. Choice depends on speed requirements, number of slaves, and available MCU pins. Since both interfaces are fully supported, designers can evaluate protocol overhead versus bandwidth needs.

How does the maximum clock speed of 20MHz affect real-time task scheduling in ATMEGA164P-20AUR-based systems?: At 20MHz, the ATMEGA164P-20AUR executes one instruction per cycle (single-cycle AVR core), enabling deterministic response times. This allows reliable execution of tasks with millisecond-level deadlines, such as motor control or data logging. However, interrupt latency and context switching overhead must still be accounted for in real-time operating systems or state machines.

What precautions should be taken when programming the ATMEGA164P-20AUR via ISP?: During In-System Programming (ISP), the RESET pin must remain asserted to enter programming mode. Clocking frequencies during programming must not exceed 4MHz, so a slower programmer interface than the device’s operational speed is required. Additionally, disabling Watchdog Timer during erase/write cycles prevents unintended resets that could corrupt firmware.

Does the ATMEGA164P-20AUR support USB connectivity natively?: No, the ATMEGA164P-20AUR lacks native USB hardware. To implement USB communication, an external USB-to-UART bridge or dedicated USB controller chip must be added alongside software handling of serial protocol translation. This increases bill-of-materials cost and board space compared to MCUs with built-in USB peripherals.

How does the Moisture Sensitivity Level (MSL) rating of 3 for ATMEGA164P-20AUR inform assembly process controls?: MSL 3 indicates the ATMEGA164P-20AUR can withstand up to 168 hours of exposure to ambient humidity before requiring baking to prevent popcorning during reflow. Manufacturers must track shelf life and storage conditions, especially after tape-and-reel unpacking, to ensure reliability in mass production environments.

What role does the Watchdog Timer play in robust firmware design using ATMEGA164P-20AUR?: The Watchdog Timer (WDT) automatically resets the MCU if software hangs due to infinite loops or unhandled exceptions. Configuring WDT with an appropriate timeout (16ms to 8s) adds resilience in field-deployed devices. However, developers must periodically reset WDT within expected execution windows; failure to do so triggers unintended reboots, complicating debugging.

How does the choice between internal vs. external voltage reference affect ADC accuracy in ATMEGA164P-20AUR applications?: Using the internal 1.1V bandgap reference improves consistency across temperature and supply variations but limits measurement range. For higher precision or wider input spans, an external precision voltage reference should be connected to AREF. External references often achieve ±0.5% accuracy, whereas the internal source may drift beyond ±2% under extreme conditions.

What considerations apply when cascading multiple ATMEGA164P-20AUR units in a distributed control system?: Although possible via SPI or I2C, coordinating multiple ATMEGA164P-20AUR devices requires careful attention to bus capacitance, pull-up resistor values, and arbitration logic. Each unit consumes static current even in sleep, so total system power budget must include all nodes. Isolation between subsystems may be preferable to shared bus architectures to avoid fault propagation.

How does the absence of advanced debugging interfaces impact development time for ATMEGA164P-20AUR projects?: Without JTAG or SWD support, debugging relies on software-based techniques such as printf-style tracing over UART or breakpoint simulation via self-programming. This increases development effort and risk of introducing bugs during debugging phases. Hardware-assisted debuggers are unavailable, so thorough unit testing becomes more critical.

What is the significance of the HTSUS code EAR99 for ATMEGA164P-20AUR in global supply chains?: The HTSUS classification EAR99 means the ATMEGA164P-20AUR is subject to U.S. Export Administration Regulations but generally qualifies for simplified licensing due to low encryption content. It simplifies international procurement logistics for most commercial applications, though end-use verification may still be required in certain jurisdictions.

Why might a designer choose ATMEGA164P-20AUR over a newer AVR model despite similar specifications?: Legacy designs leveraging existing toolchains, certified firmware, or long-term availability agreements may justify continued use of ATMEGA164P-20AUR. Its proven reliability in automotive and industrial deployments, combined with extensive community support and mature compilers, reduces qualification risks even if newer parts offer marginal improvements.

Parts with Similar Specifications

The three parts on the right have similar specifications to Microchip Technology ATMEGA164P-20AUR

Product Attribute
Part Number	ATMEGA164P-20MUR	ATMEGA164P-20AQR	ATMEGA164P-20MCUR	ATMEGA164P-20AU
Manufacturer	Microchip Technology	Microchip Technology	Microchip Technology	Microchip Technology
Program Memory Size	-	-	-	-
Core Processor	-	-	-	-
Voltage - Supply (Vcc/Vdd)	-	-	-	-
Package / Case	-	196-LFBGA	16-DIP (0.300', 7.62mm)	64-VFQFN Exposed Pad
Number of I/O	-	-	-	-
Supplier Device Package	-	196-NFBGA (12x12)	16-PDIP	64-VQFN (9x9)
Connectivity	-	-	-	-
Program Memory Type	-	-	-	-
Peripherals	-	-	-	-
Speed	-	-	-	-
Base Product Number	-	DAC34H84	MAX500	ADS62P42
Data Converters	-	-	-	-
Core Size	-	-	-	-
Package	-	Tape & Reel (TR)	Tube	Tape & Reel (TR)
EEPROM Size	-	-	-	-
Oscillator Type	-	-	-	-
Mounting Type	-	Surface Mount	Through Hole	Surface Mount
RAM Size	-	-	-	-
Series	-	-	-	-
Operating Temperature	-	-40°C ~ 85°C	0°C ~ 70°C	-40°C ~ 85°C

ATMEGA164P-20AUR Datasheet PDF

Download ATMEGA164P-20AUR pdf datasheets and Microchip Technology documentation for ATMEGA164P-20AUR - Microchip Technology.

Datasheets: ATmega164_324_644P/V Appendix.pdf
PCN Design/Specification: ATMEGA Datasheet 12/Dec/2018.pdf Marking Chgs 11/Jul/2017.pdf
HTML Datasheet: Cylindrical Battery Holders.pdf
PCN Packaging: Boxes 07/Dec/2016.pdf Transfer to Microchip/Label/Pkg 5/Sep/2016.pdf
PCN Other: 2.73KHz.pdf

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Customer Reviews

Evaluation: 10 Articles

Nath***rooks

Jun 11, 2026

Installed this power component in a converter board. Output remained stable under different load conditions and thermal performance was better than expected.
Dani***alkerTech

Jun 1, 2026

Product works, but setup took more effort than expected. Once configured the MCU ran reliably, although documentation support felt older compared with newer platforms. Fine for maintenance projects.
Yuki***aka88

May 26, 2026

信号通信プロジェクトでこのRS-485トランシーバーを使用しました。設置は簡単で、長距離ケーブルでも通信は安定していました。消費電力も、以前使用していたものより低くなっています。
Stev***aker

May 20, 2026

Solid diode for power rectification. Works well in switching circuits.
Bran***Lewis

May 11, 2026

Compact FPGA with good performance. Suitable for basic signal processing tasks.
Oliv***arris

May 7, 2026

Reliable I/O expander. Works well in embedded control applications.
Jess***Jones

Apr 17, 2026

It offers good value for the price, and the specifications match the description. I’ve been using it for two days with no issues, and I’ll definitely buy it again if I need it in the future.
Mich***Smith

Apr 17, 2026

Shipping was on time, the component pins are neatly aligned, and I tested 10 of them with a multimeter—all readings were within the specified range. Highly recommended.
Aman***arris

Apr 3, 2026

It was great—the entire process, from placing the order to receiving the package, went very smoothly. The components were consistent, the price was fair, and I had a very pleasant shopping experience.
Mike***nch

Apr 3, 2026

Better than expected! The resistance and capacitance readings were spot-on, and it passed the test on the first try. The service was reliable, and the packaging was thoughtful—I highly recommend it.

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Shipment

Delivery Time

In-stock items can be shipped within 24 hours. Some parts will be arranged for delivery within 1-2 days from the date all items arrive at our warehouse. And Allelco ships order once a day at about 17:00, except Sunday. Once the goods are shipped, the estimated delivery time depends on the shipping methods and Delivery destination. The table below shows are the logistic time for some common countries.

Delivery Cost

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Delivery Method

Global Common Shipment by DHL / UPS / FedEx / TNT / EMS / SF we support.
Others more shipping ways, please get in touch with your customer manager.

Common Countries Logistic Time Reference
Region	Country	Logistic Time(Day)
America	United States	5
America	Brazil	7
Europe	Germany	5
	United Kingdom	4
	Italy	5
Oceania	Australia	6
Oceania	New Zealand	5
Asia	India	4
Asia	Japan	4
Middle East	Israel	6

DHL & FedEx Shipment Charges Reference
Shipment charges(KG)	Reference DHL(USD$)
0.00kg-1.00kg	USD$30.00 - USD$60.00
1.00kg-2.00kg	USD$40.00 - USD$80.00
2.00kg-3.00kg	USD$50.00 - USD$100.00

Note:: The above table is for reference only. There may have some data bias for the uncontrollable factors.
Contact us if you have any questions.

QC (Quality Warranty)
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Allelco is committed to exceeding customer expectations through customer service excellence, order accuracy, and on-time delivery.
This is achieved through our commitment to the continual improvement of our processes, services, and products.

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We eliminate defective components and ensure the stable operation of electronic devices through professional quality standards.

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Packaging

Electrostatic Discharge Protection and Handling

All electrostatic-sensitive components are handled in accordance with electrostatic discharge control procedures. The products are hermetically sealed in anti-static safe packaging to prevent electrostatic damage. Appropriate labeling is also applied for identification and traceability. This ensures product integrity during storage, handling and transportation.

ESD

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ISO 9001: 2015
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