ATMEGA324P-20MQR - 8-Bit AVR MCU 20MHz 32KB Flash | Microchip
MPN: ATMEGA324P-20MQR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.92 | $5.92 |
| 10 | $5.4 | $54.00 |
| 100 | $4.95 | $495.00 |
| 500 | $4.62 | $2,310.00 |
| 1,000 | $4.3 | $4,300.00 |
ATMEGA324P-20MQR Overview
A microcontroller unit (MCU) is a single integrated circuit that combines a processor core, non-volatile program memory, RAM, and peripherals such as timers, UARTs and ADCs into one chip. The ATmega family sits within the broader hierarchy of 8-bit RISC microcontrollers, which are widely used where deterministic, low-power embedded control is required. AVRs execute most instructions in a single clock cycle, delivering high code efficiency for their class.
Key features of this device include 32 general purpose I/O lines, 32 general purpose working registers, read-while-write Flash for in-system programming, a real time counter, and the picoPower technology suite for low sleep-mode consumption. The AVR core achieves near 20 MIPS throughput at 20 MHz, and three flexible timer/counters with compare modes support PWM generation and precise event timing.
Architecturally, the AVR uses a Harvard structure with separate program and data buses, allowing simultaneous Flash and SRAM access. In-system self-programming enables boot-loader firmware updates in the field, while the JTAG interface supports boundary scan, on-chip debug, and programming on the 44-VQFN package.
Typical applications include industrial automation controllers, consumer appliances, and battery-operated instrumentation, where the combination of 32 KB Flash, rich peripherals and picoPower sleep modes fits both cost-sensitive and power-sensitive designs.
Design consideration: the 44-VQFN exposed pad must be soldered to a grounded PCB land pattern for reliable thermal and electrical performance; verify the Flash clock constraints between 4.5 V and 5.5 V supply domains in the manufacturer datasheet before finalizing the crystal selection.
This page synthesizes distributor pricing, drop-in alternatives, pinout guidance, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for ATMEGA324P-20MQR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ATMEGA324P-20MQR (same form factor and footprint) — differing in Package, EEPROM, Instructions, SRAM, Supply Voltage Range.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA324PA-MUR
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATMEGA324A-MU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$3.9 / Unit
View Datasheet →ATMEGA32A-MNR
✅ Drop-In✓ In Stock
$3.75 / Unit
View Datasheet →ATMEGA644PA-MUR
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATMEGA1284P-MUR
✅ Drop-In ⚠️ 参数待验证✓ In Stock
Contact for price
View Datasheet →ATMEGA324P-20MQR Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Core Size | 8-Bit |
| Maximum Clock Frequency | 20 MHz |
| Flash Memory | 32 KB (16K x 16) |
| Flash Type | ISP FLASH with read-while-write |
| EEPROM | 1 KB |
| SRAM | 2 KB |
| General Purpose I/O | 32 I/O lines |
| Working Registers | 32 general purpose registers |
| Package | 44-VQFN (7x7 mm) with Exposed Pad |
| Mounting Type | Surface Mount |
| Peripherals | Real time counter, three flexible timer/counters |
| Programming Interface | ISP (in-system self-programming) |
| Low Power Technology | picoPower |
ATMEGA324P-20MQR 44-vqfn (7x7 mm) with exposed pad Pin Configuration Guide
Pin configuration for ATMEGA324P-20MQR (44-vqfn (7x7 mm) with exposed pad package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for ATMEGA324P-20MQR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA324P-20MQR is suitable for 6 applications: Industrial Automation Controllers, Consumer Appliances, Battery-Powered Instrumentation, Embedded Communication Nodes, Automotive Aftermarket Electronics, Hobbyist and Educational Embedded Platforms.
Industrial Automation Controllers
The ATMEGA324P-20MQR fits factory automation nodes such as sensor hubs, motor control boards, and PLC sub-controllers. Its 20 MHz AVR core delivers roughly 20 MIPS single-cycle throughput, while 32 KB of ISP Flash with read-while-write enables field firmware updates via boot-loader, reducing maintenance visits. Three flexible timer/counters generate complementary PWM outputs for motor drive and control loops, and the 32 GPIO lines interface directly with relays, optocouplers, and front-panel controls. The 44-VQFN (7x7 mm) package conserves board area in compact DIN-rail modules, while the exposed pad improves ground integrity for industrial EMI environments. picoPower sleep modes also let the controller meet standby power budgets between duty cycles.
Recommended
Consumer Appliances
White goods, HVAC controls, and small appliances benefit from the ATMEGA324P-20MQR's balance of cost, memory, and low power. The 1 KB EEPROM stores calibration data, user settings, and wear counters that must survive power cycles, while 2 KB SRAM and 32 KB Flash accommodate state machines, display drivers, and communication protocols typical of appliance boards. In-system self-programming supports factory-line programming and post-assembly firmware fixes. The real time counter supports clock and scheduling functions in ovens and washing machines. Tape-and-reel MQR packaging supports high-volume automated pick-and-place assembly, and the 7x7 mm VQFN footprint suits dense multi-board appliance architectures.
Recommended
Battery-Powered Instrumentation
Portable meters, data loggers, and handheld instruments exploit the ATMEGA324P-20MQR's picoPower technology, which minimizes consumption in idle, power-down, and power-save sleep modes between measurements. The 20 MHz maximum clock allows burst processing of ADC data or math routines, then rapid return to deep sleep to extend battery life. The real time counter keeps accurate timekeeping during power-save sleep for logging applications, and the 1 KB EEPROM preserves logged calibration or threshold data across battery swaps. Choosing the ATMEGA324PA-MUR drop-in alternative further reduces sleep current for multi-year battery designs while requiring no PCB or firmware changes.
Recommended
Embedded Communication Nodes
Serial gateways, protocol converters, and networked sensor nodes use the ATMEGA324P-20MQR's hardware serial resources and JTAG-based debugging. The AVR USART handles RS-232/RS-485 links while SPI and two-wire interfaces connect to transceivers, EEPROMs, and network co-processors. Read-while-write Flash permits parameter storage and firmware updates without interrupting the running program, an advantage for nodes that cannot be taken offline. The 32 working registers reduce context-switch overhead in interrupt-driven protocol stacks at 20 MHz. The 44-VQFN exposed pad provides a low-impedance ground reference, important for signal integrity on communication lines in electrically noisy environments.
Recommended
Automotive Aftermarket Electronics
Non-safety-critical automotive aftermarket modules - telematics dongles, accessory controllers, retrofit lighting controls - can leverage the ATMEGA324P-20MQR's extended temperature-capable packaging options and robust peripheral set within its validated supply range. Its three timer/counters with compare modes generate precise PWM for lamp dimming and actuator control, while the USART interfaces with GPS or cellular modules common in telematics. The 44-VQFN (7x7) surface-mount package withstands automotive assembly reflow profiles. Designers should confirm the exact operating temperature grade on the datasheet and select the appropriate speed/voltage combination; where AEC-grade parts are mandatory, evaluate Microchip's automotive-qualified AVR variants instead.
Recommended
Hobbyist and Educational Embedded Platforms
The ATmega family underpins popular educational and maker platforms, and the ATMEGA324P-20MQR extends that ecosystem with 32 KB Flash and 32 I/O lines in a reflowable VQFN package for advanced student projects and small-batch products. Development requires only low-cost ISP programmers, and the well-documented AVR instruction set - mostly single-cycle - simplifies teaching of computer architecture fundamentals. JTAG access on the 44-pin device allows step-by-step on-chip debugging in laboratory courses. The 1 KB EEPROM demonstrates non-volatile storage exercises, and three timer/counters support motor, servo, and audio experiments, making the device a versatile platform for project-based electronics education.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA324P-20MQR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA324PA-MUR | ATMEGA324A-MU | ATMEGA32A-MNR | ATMEGA644PA-MUR | ATMEGA1284P-MUR |
|---|---|---|---|---|---|---|
| Package | 44-VQFN (7x7 mm) Exposed Pad | 44-VQFN (7x7 mm) - same | 44-VQFN (7x7 mm) - same | 44-VQFN (7x7 mm) - same | 44-VQFN (7x7 mm) - same | 44-VQFN (7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 32 KB (16K x 16) | 32 KB | 32 KB | 32 KB | 64 KB | 128 KB |
| SRAM | 2 KB | 2 KB | 2 KB | 2 KB | 4 KB | 16 KB |
| EEPROM | 1 KB | 1 KB | 1 KB | 1 KB | 2 KB | 4 KB |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 16 MHz | 20 MHz | 20 MHz |
| Low Power Technology | picoPower (P die) | picoPower (PA die, lower current) | Standard (A die) | None (legacy die) | picoPower (PA die) | picoPower (P die) |
| Lifecycle / Migration Note | Active; Microchip notes ATMEGA324PA as newer device | Active - recommended migration target | Active - newer die generation | Legacy die family | Active | Active |
Key Differentiators
- Lowest-power option in the compatible 44-VQFN family (vs ATMEGA324A-MU)
- 4x Flash and 8x SRAM headroom without footprint change (vs ATMEGA1284P-MUR)
- picoPower efficiency versus legacy ATmega32 core (vs ATMEGA32A-MNR)
Design Notes
The 44-VQFN (7x7 mm) package has an exposed die-attach pad on the underside that must be connected to a PCB ground land pattern. Follow Microchip's recommended QFN footprint: an array of thermal vias under the pad (typically filled and capped) to provide both electrical ground and heat spreading. Also provide adequate decoupling - place a 100 nF ceramic capacitor within 2 mm of the VCC pin plus a bulk 10 uF capacitor near the supply entry. Do not float the exposed pad; floating ground references cause intermittent reset and JTAG failures.
Fuse-bit misconfiguration is the most common field failure mode for ATmega devices: setting clock fuses for an external crystal that is not populated, or disabling SPI/reset, can brick the device and require high-voltage parallel programming for recovery. Verify clock source fuses against your actual oscillator circuit before ISP programming, and reserve a test-point or header for the ISP SPI pins (MOSI, MISO, SCK, RESET) even in production layouts. Additionally, confirm the voltage-versus-frequency safe operating graph in the Microchip datasheet before running 20 MHz at reduced supply voltage.
Route the crystal circuit with short, direct traces and place load capacitors within 1-2 mm of the XTAL pins, guarding with ground pour. Keep ISP SPI lines and JTAG traces away from switching nodes such as relay drivers and PWM outputs; series 22-33 ohm resistors on long SPI runs dampen ringing at 20 MHz clock rates. For boards using the USART over RS-485 in industrial environments, add TVS protection at the connector and route the pair as a matched differential over a continuous ground reference.
Compliance Information
Compliance status not explicitly stated in the provided web data; confirm RoHS/REACH status on the Microchip product page or distributor certificate of conformance before procurement.