ATMEGA324A-CUR - 8-bit AVR MCU 32KB Flash 20MHz | Microchip
MPN: ATMEGA324A-CUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.48 | $3.48 |
| 10 | $3.13 | $31.30 |
| 100 | $2.82 | $282.00 |
| 500 | $2.54 | $1,270.00 |
| 1,000 | $2.29 | $2,290.00 |
ATMEGA324A-CUR Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a processor core, program memory, data memory, and peripherals such as timers, UARTs, and ADCs on one die. Within the power-management hierarchy of embedded systems, the MCU sits at the application layer: AVR MCUs like the ATmega324A execute control loops, communication, and signal acquisition, replacing multi-chip discrete logic with one programmable device.
Key features include an advanced RISC architecture with 131 powerful instructions, most executing in a single clock cycle; 32 general-purpose working registers; and 32 general-purpose I/O lines. The read-while-write ISP Flash enables self-programming for firmware updates in the field, while the real-time counter plus three flexible timers support precision timing tasks.
Technically, the ATmega324A pairs its pipelined AVR core with a 10-bit ADC, multiple serial interfaces, and an on-chip debug/programming channel via In-Circuit Serial Programming (ICSP), compatible with Microchip MPLAB SNAP and Atmel-ICE tools. The wide 1.8V to 5.5V operating range covers 2.5V, 3.3V, and 5V rails, letting one design span battery and industrial voltage domains.
Typical applications include industrial sensor nodes, consumer appliance control, and portable battery-powered devices where the compact 5x5 mm VFBGA footprint saves PCB area.
Design consideration: at 20MHz the part achieves up to 20 MIPS, but full-speed operation at the lowest voltage is derated per the datasheet frequency-versus-voltage curve, so check safe operating margins for 1.8V designs.
This page synthesizes distributor pricing, drop-in family alternatives, and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for ATMEGA324A-CUR β 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 ATMEGA324A-CUR (same form factor and footprint).
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA324PA-CU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$2.45 / Unit
View Datasheet βATMEGA644A-CU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA644PA-CU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA1284-CU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA1284P-CU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA324A-CUR Maximum Ratings & Electrical Characteristics
| Core Processor | AVR |
| Core Size | 8-bit |
| Speed | 20 MHz |
| Program Memory Size | 32 KB Flash |
| EEPROM Size | 1 KB |
| RAM Size | 2 KB |
| Supply Voltage Range | 1.8 V to 5.5 V |
| Voltage - Supply (Vcc/Vdd) | 1.8V ~ 5.5V |
| Number of I/O | 32 |
| General Purpose I/O Ports | 32 |
| ADC Resolution | 10 bit |
| Package | 49-VFBGA (5x5 mm) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (T/R) |
| Series | AVR ATmega |
| Life Cycle Stage | ACTIVE |
| Instructions | 131 instructions, most single-cycle |
ATMEGA324A-CUR 49-vfbga (5x5 mm) Pin Configuration Guide
Pin configuration for ATMEGA324A-CUR (49-vfbga (5x5 mm) 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 ATMEGA324A-CUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA324A-CUR is suitable for 6 applications: Industrial Sensor Nodes, Portable Battery-Powered Devices, Consumer Appliance Control, Embedded Communication Interfaces, Medical and Health Monitoring Devices, Hobbyist and Maker Embedded Projects.
Industrial Sensor Nodes
The ATMEGA324A-CUR fits industrial sensor nodes because its 10-bit ADC digitizes analog sensor outputs directly, while 32KB Flash and 2KB SRAM hold protocol stacks such as Modbus or custom RS-485 firmware. The 1.8V to 5.5V supply range allows the same PCB design to run from 3.3V logic or noisy 5V industrial rails without redesign. The 49-ball VFBGA 5x5 mm footprint keeps node electronics compact for dense installations. Three timers plus the real-time counter support scheduled sampling and timestamped logging, and read-while-write ISP Flash permits field firmware updates over the network without a hardware swap, reducing maintenance cost in deployed installations.
Recommended
Portable Battery-Powered Devices
The ATMEGA324A-CUR suits portable, battery-powered products because it operates from 1.8V, matching single-cell lithium and two-cell alkaline chemistries directly without a boost converter, reducing board area and quiescent losses. Its AVR core executes most of 131 instructions in a single 20MHz clock cycle, delivering up to 20 MIPS so tasks finish quickly and the MCU can return to idle sleep modes to stretch battery life. The 5x5 mm VFBGA package minimizes PCB footprint for wearables and handheld enclosures. Designers requiring even lower sleep current should evaluate the pin-compatible ATMEGA324PA PicoPower variant, which drops standby current further at identical performance and footprint.
Recommended
Consumer Appliance Control
In consumer appliance control boards, the ATMEGA324A-CUR provides the 32 GPIO lines needed for keypad matrices, LED or LCD segment drives, relay outputs, and encoder inputs in one chip. The 32KB ISP Flash accommodates mature feature-rich firmware with room for OTA-style updates using the read-while-write self-programming capability, and 1KB EEPROM stores calibration and user settings across power cycles. The 10-bit ADC reads temperature sensors and user potentiometers, while the real-time counter maintains clock functions during standby. The compact VFBGA-49 package suits dense main-PCB layouts typical of modern white goods, and the 20MHz throughput comfortably handles closed-loop motor or heater control.
Recommended
Embedded Communication Interfaces
The ATMEGA324A-CUR serves protocol-conversion and communication modules because its AVR core plus hardware timers generate and capture precise serial timing for UART, SPI, and software-defined buses. With 20 MIPS single-cycle throughput, firmware can bit-bang legacy protocols while servicing the hardware USART concurrently. The 2KB SRAM buffers packet frames, and the 49-VFBGA footprint integrates converters into dongles and gateways where board space is constrained. The real-time counter supports time-stamped logging in data-collection applications, and in-system programming via ICSP using MPLAB SNAP or Atmel-ICE enables fast production flashing directly on the assembled PCB without sockets or test fixtures.
Recommended
Medical and Health Monitoring Devices
For medical and health monitoring products, the ATMEGA324A-CUR combines a low-noise 10-bit ADC with enough Flash (32KB) for signal-processing routines such as digital filtering and baseline detection used in pulse, temperature, or bioimpedance measurements. The 1.8V to 5.5V supply range supports 3V coin-cell or 3.6V lithium designs, and single-cycle instruction execution allows burst sampling followed by aggressive sleep to conserve battery. The 1KB EEPROM retains patient calibration data through battery replacement. Note: devices intended for certified medical end-use must undergo the applicable regulatory validation; the MCU is the compute element, not a certified component itself.
Recommended
Hobbyist and Maker Embedded Projects
The ATMEGA324A-CUR appeals to advanced maker projects that outgrow an ATmega328P: the additional 32 general-purpose I/O lines and four ports support larger LED matrices, many-sensor arrays, and multi-bus designs, while 32KB Flash and 2KB SRAM run larger sketches. Community support exists through the MightyCore Arduino hardware package on GitHub, which covers the ATmega324 family with familiar Arduino tooling, and standard ICSP programming works with MPLAB SNAP or USBasp-class programmers. The VFBGA-49 package requires reflow soldering, so hobbyists typically use breakout boards or choose the TQFP ATMEGA324A-AU for hand assembly; the firmware remains fully portable between the two.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA324A-CUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA324PA-CU | ATMEGA644A-CU | ATMEGA1284-CU |
|---|---|---|---|---|
| Package | 49-VFBGA (5x5 mm) | 49-VFBGA (5x5 mm) - same | 49-VFBGA (5x5 mm) - same | 49-VFBGA (5x5 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory (Flash) | 32 KB | 32 KB | 64 KB | 128 KB |
| SRAM | 2 KB | 2 KB | 4 KB | 16 KB |
| Max Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| Low-Power Features | Standard ATmega power modes | PicoPower (lower sleep/active current) | Standard ATmega power modes | Standard ATmega power modes |
Key Differentiators
- Same 32KB capability with VFBGA-49 footprint (vs ATMEGA324PA-CU)
- More memory headroom available in the same footprint (vs ATMEGA644A-CU)
- Wider voltage range than many 8-bit competitors (vs PIC16C57T-10/SO)
Design Notes
The ATMEGA324A-CUR operates from 1.8V to 5.5V, but the maximum safe clock frequency is voltage-dependent: at 20MHz the device should run near the upper end of the supply range. Check the frequency-versus-VCC curve in the Microchip ATmega324A datasheet before running full speed at 3.3V or below; an estimated safe configuration is 20MHz at 4.5V to 5.5V and roughly 13MHz to 16MHz at 3.3V (derate per curve). Decouple VCC with a 100nF ceramic capacitor at each supply ball plus bulk 10uF.
The 49-VFBGA (5x5 mm, 0.8mm-class ball pitch) requires a reflow profile and fine-pitch PCB capability; verify your fabricator supports the ball-pad geometry in the Microchip package drawing. Use via-in-pad or dogbone fanout with 0.2mm-0.25mm vias for the four port rings, and keep the ICSP/ISP routing (two I/O pins plus RESET) short and accessible to an 8-pin SIL header for MPLAB SNAP or Atmel-ICE programming, as recommended in Microchip's product documentation.
Ordering-code suffixes matter: ATMEGA324A-CUR (tape and reel) and ATMEGA324A-CU (tray) are electrically identical, but ATMEGA324A-AU is a 44-pin TQFP and is NOT footprint-compatible with this 49-ball VFBGA. Firmware is portable across all three, but PCBs cannot be reused. Also, EEPROM writes are endurance-limited; implement wear-leveling if your application writes calibration data frequently, and reserve the read-while-write Flash self-programming region carefully so live code execution is never overwritten during field updates.
Compliance Information
Compliance data was not explicitly stated in the provided web data; consult the official Microchip product page and Environmental datasheet for current RoHS/REACH status of ATMEGA324A-CUR.
