ATMEGA329-16AUR - AVR 8-bit MCU 16MHz 32KB LCD | Microchip
MPN: ATMEGA329-16AUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.65 | $2.65 |
| 10 | $2.62 | $26.20 |
| 100 | $2.45 | $245.00 |
| 500 | $2.3 | $1,150.00 |
| 1,000 | $2.15 | $2,150.00 |
ATMEGA329-16AUR Overview
An 8-bit AVR microcontroller is a Harvard-architecture RISC processor that executes most of its 131 powerful instructions in a single clock cycle, sitting within the broader hierarchy of microcontrollers as a member of the AVR ATmega family of power-management-capable embedded processors. The integrated segment LCD driver distinguishes the ATmega329 from general-purpose parts such as the ATmega328P, making it a strong fit for battery-fronted display products.
Key features include read-while-write self-programming Flash, 54 general-purpose I/O lines, 32 general-purpose working registers, a JTAG (IEEE 1149.1 compliant) boundary-scan and on-chip debug interface, an 8-channel 10-bit ADC, and an on-chip LCD controller capable of driving up to 4x25 segment/common combinations with three selectable duty schemes. The advanced RISC architecture achieves up to 16 MIPS throughput at 16 MHz.
Technically, the device combines a fast single-cycle ALU with in-system self-programmable Flash, allowing firmware updates in the field without a separate programmer. Power management is handled through idle, ADC noise reduction, power-save, power-down, and standby sleep modes.
Typical applications include utility metering with LCD displays, handheld measurement instruments, industrial control panels, and consumer appliances requiring integrated segment-LCD drive.
A key design consideration is the 5 V supply requirement: the -16 speed grade needs 4.5 V to 5.5 V, so battery designs should consider the ATmega329V low-voltage variant instead.
This page synthesizes distributor pricing, drop-in alternatives within the same 64-TQFP footprint, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA329-16AUR 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 ATMEGA329-16AUR (same form factor and footprint) β differing in Package, Operating Temperature, RoHS Status, ADC, Maximum Clock Frequency.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA329-16AU
β Drop-Inβ In Stock
$8.45 / Unit
View Datasheet βATMEGA329-16AI
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
Contact for price
View Datasheet βATMEGA3290PA-AUR
β Drop-Inβ In Stock
$2.95 / Unit
View Datasheet βATMEGA3290V-8AUR
β Drop-Inβ In Stock
$2.3 / Unit
View Datasheet βATMEGA325PA-AUR
β Drop-Inβ In Stock
$3.9 / Unit
View Datasheet βATMEGA3250PA-AUR
β Drop-Inβ In Stock
$2.98 / Unit
View Datasheet βATMEGA329-16AUR Maximum Ratings & Electrical Characteristics
| Core Processor | AVR 8-bit RISC |
| Core Size | 8-bit |
| Speed | 16 MHz |
| Program Memory Size | 32 KB (16K x 16) FLASH |
| EEPROM Size | 1 KB |
| RAM Size | 2 KB SRAM |
| Supply Voltage Range | 4.5 V to 5.5 V |
| Number of I/O | 54 general purpose I/O lines |
| LCD Controller | Integrated segment LCD driver |
| ADC | 8-channel 10-bit |
| JTAG | Yes (IEEE 1149.1 boundary scan / on-chip debug) |
| Instructions | 131 powerful instructions, most single-cycle |
| Package | 64-TQFP (14x14 mm, 0.8 mm pitch) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (industrial, per ATMEGA329-16AI grade family) |
| Packaging | Tape & Reel (R suffix) |
| Life Cycle Stage | ACTIVE |
| RoHS Status | Compliant |
ATMEGA329-16AUR 64-tqfp (14x14 mm, 0.8 mm pitch) Pin Configuration Guide
Pin configuration for ATMEGA329-16AUR (64-tqfp (14x14 mm, 0.8 mm pitch) 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 ATMEGA329-16AUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA329-16AUR is suitable for 6 applications: Utility Metering with LCD Display, Handheld Measurement Instruments, Industrial Control Panels and HMI, Consumer Appliance Displays, Building Automation Sensors and Thermostats, POS Terminals and Card Readers.
Utility Metering with LCD Display
The ATMEGA329-16AUR fits electricity, water, and heat meter designs because it integrates a segment LCD controller that drives consumption and tariff digits directly, eliminating an external LCD driver IC and its associated traces. The 8-channel 10-bit ADC samples shunt or Hall-effect sensor front ends, while 1 KB EEPROM stores metrology calibration constants and tamper event logs through power cycles. Self-programmable Flash with read-while-write support enables field firmware updates required by changing utility regulations without replacing the meter. In a typical topology the MCU runs from a 5 V derived supply at 16 MHz, entering power-save sleep between measurement intervals; the 54 I/O lines handle pulse inputs, reed-switch tamper detection, and an optical communication port, delivering a single-chip meter front end.
Recommended
Handheld Measurement Instruments
Portable multimeters, insulation testers, and environmental meters benefit from the ATMEGA329-16AUR's combination of a directly driven LCD and a 10-bit, 8-channel ADC. The integrated LCD controller renders readings and units without a display driver, reducing PCB area in compact handheld enclosures, while the ADC multiplexer sequences voltage, current, and resistance measurement channels through a single analog front end. JTAG on-chip debugging via the IEEE 1149.1 interface shortens firmware development for calibration routines stored in the 1 KB EEPROM. In this application the device typically runs at 16 MHz during measurement bursts and drops to power-down sleep between user interactions; the 5 V operating range suits instruments powered by four NiMH cells or a 9 V battery through a linear regulator, though the ATmega329V variant should be evaluated for direct battery operation.
Recommended
Industrial Control Panels and HMI
Machine and process control panels use the ATMEGA329-16AUR as a low-cost human-machine interface controller: the LCD driver shows setpoints, alarm codes, and status symbols, while 54 general-purpose I/O lines scan keypads, drive relays, and read limit switches. The industrial temperature rating and 4.5-5.5 V tolerance suit 24 V industrial panels that derive a regulated 5 V rail, and the watchdog timer plus brown-out detection maintain safe behavior during supply transients common in motor-heavy environments. Boundary-scan JTAG supports production board testing of panel wiring without bed-of-nails access. Firmware stored in the 32 KB Flash typically implements a modbus-style serial protocol; at 16 MHz there is ample headroom for display refresh, key scanning, and communication simultaneously, making the part a proven single-chip panel controller.
Recommended
Consumer Appliance Displays
Ovens, washing machines, and thermostats employ the ATMEGA329-16AUR where a custom segment LCD shows cycles, temperatures, and remaining time. The on-chip LCD controller supports selectable duty schemes and contrast control, driving glass directly and keeping bill-of-materials cost low in high-volume appliances. The self-programmable Flash supports manufacturing-line calibration: final-test equipment reprograms trim and user-preference data into EEPROM without a separate socket. The 5 V supply integrates cleanly with transformer-derived appliance power rails, and sleep modes keep standby consumption within energy-label limits when the appliance is idle. Because 32 KB Flash accommodates menu logic, sensor linearization, and safety interlock code in C, most appliance designs complete firmware within the single-chip memory budget, avoiding external memory and its failure modes.
Recommended
Building Automation Sensors and Thermostats
Room thermostats, occupancy sensors, and zone controllers in building automation use the ATMEGA329-16AUR's LCD drive for setpoint and schedule display, its ADC for NTC temperature sensing, and its USART for RS-485 field bus communication. The 2 KB SRAM buffers protocol frames while the LCD is refreshed, and the 1 KB EEPROM stores occupancy schedules and commissioning parameters that survive power loss. In wall-mounted, battery-backed installations the device sleeps in power-save mode, waking on a timer or button interrupt; designers targeting primary-cell operation should instead specify the picoPower ATMEGA325PA-AUR drop-in, which shares the same footprint but cuts active and sleep currents significantly. The 16 MHz 5 V rating of the ATMEGA329-16AUR suits bus-powered thermostats with a regulated supply.
Recommended
POS Terminals and Card Readers
Point-of-sale keypads and simple card reader terminals leverage the ATMEGA329-16AUR to scan matrix keypads, drive a status LCD, and communicate with a main payment processor over UART. The device's 54 I/O lines cover a 4x4 keypad, backlight control, card-insertion sensing, and buzzer drive from one chip, while 32 KB Flash holds key-scanning, display, and encrypted-communication routines. The watchdog timer supports the transaction-integrity requirements of payment peripherals, restarting the terminal on a hung state, and the 5 V rail simplifies integration with legacy POS mainboards. JTAG boundary scan accelerates production test of keypad wiring and LCD connections. For designs migrating to lower standby power, the pin-compatible ATMEGA3290PA-AUR provides an in-footprint upgrade without PCB changes.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA329-16AUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA329-16AU | ATMEGA3290PA-AUR | ATMEGA325PA-AUR | ATMEGA3290V-8AUR |
|---|---|---|---|---|---|
| Package | 64-TQFP (14x14 mm) | 64-TQFP (14x14 mm) - same | 64-TQFP (14x14 mm) - same | 64-TQFP (14x14 mm) - same | 64-TQFP (14x14 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Speed | 16 MHz | 16 MHz | 20 MHz (PA picoPower) | 20 MHz (PA picoPower) | 8 MHz |
| Flash | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB |
| SRAM | 2 KB | 2 KB | 4 KB | 2 KB | 4 KB |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 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 |
| LCD Drive | Up to 4x25 segments | Up to 4x25 segments | Up to 4x40 segments | Up to 4x25 segments | Up to 4x40 segments |
| Low-Power Technology | Standard AVR core | Standard AVR core | picoPower | picoPower | Low-voltage V-variant |
| Packaging | Tape & Reel (R) | Tray | Tape & Reel (R) | Tape & Reel (R) | Tape & Reel (R) |
Key Differentiators
- Integrated LCD controller in a 64-pin footprint (vs ATMEGA328P-MU)
- Pin-compatible picoPower upgrade path (vs ATMEGA3290PA-AUR)
- Single-cycle RISC throughput (vs ATMEGA3290V-8AUR)
- Largest drop-in sourcing continuity (vs ATMEGA165P-16AU)
Design Notes
The ATMEGA329-16AUR requires 4.5 V to 5.5 V for the 16 MHz speed grade; operating below 4.5 V at full clock violates the datasheet operating envelope and risks unstable execution. Derive the 5 V rail from an industrial 24 V bus via a buck regulator or from 9 V batteries via an LDO such as the MCP1702 family, and enable the on-chip brown-out detector (set BODLEVEL fuse) so the MCU resets cleanly during supply sag instead of corrupting EEPROM writes.
The LCD controller segment/common mapping differs between the ATmega329 (up to 4x25) and the larger ATmega3290 (up to 4x40); firmware written for one LCD glass will not drive the other correctly even though the pinout is compatible. When substituting a 3290-family drop-in, remap the LCDCCR/LCDDR register writes. Also note that JTAG enable fuse consumes four port pins (PF4-PF7); disable JTAG in the fuse bits if those pins are needed as GPIO.
Place 100 nF ceramic decoupling capacitors at each VCC/GND pin pair as close to the package as possible, plus 10 uF bulk capacitance near the supply entry. Keep the analog reference (AREF) node star-routed with its own 100 nF capacitor and guard it from LCD drive lines, which carry AC Commons that couple into the 10-bit ADC. The 0.8 mm pitch 64-TQFP suits standard surface-mount reflow; extend the thermal pad routing of the center die area only if ambient temperatures exceed 70 C.
LCD COM and segment lines switching at the frame frequency radiate into nearby high-impedance analog traces; route ADC inputs on the opposite board side or shield them with ground pours. For long RS-485/UART runs to the panel bus, add series termination and keep the crystal traces under 10 mm with guard ground to preserve 16 MHz oscillation start-up, especially with low-quality crystals at cold temperatures.
Compliance Information
RoHS compliance per DigiKey/Mouser listings for the ATMEGA329-16AUR. REACH, halogen-free, and conflict-minerals declarations should be confirmed via Microchip's official environmental documentation for the specific date code.
