ATMEGA329A-AU - 32KB AVR MCU, 20MHz, TQFP-64 | Microchip
Référence : ATMEGA329A-AU ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $5.2 | $5,20 |
| 10 | $4.68 | $46,80 |
| 100 | $4.16 | $416,00 |
| 500 | $3.72 | $1 860,00 |
| 1 000 | $3.31 | $3 310,00 |
ATMEGA329A-AU Présentation
An 8-bit AVR microcontroller is a Harvard-architecture RISC processor that executes most instructions in a single clock cycle, sitting within the broader hierarchy of embedded processors: microcontroller -> MCU -> embedded processor. The AVR ATmega family is widely used for cost-sensitive, low-power embedded control where integrated Flash, EEPROM, and rich peripherals reduce external component count.
Key features include a 20 MHz maximum clock frequency (up to 20 MIPS throughput at 20 MHz), 32 general-purpose working registers directly connected to the ALU, read-while-write Flash programming via ISP, and a JTAG interface supporting boundary-scan, on-chip debugging, and in-system programming. The integrated LCD controller with internal contrast control is the headline differentiator, driving segment or dot-matrix LCD glass directly without an external LCD driver.
The core runs from 2.0 V to 5.5 V (per ATmega329A family operating ranges), and three flexible timers, a 10-bit ADC, and a USART round out the peripheral set. The AVR architecture keeps interrupt latency short and deterministic, valuable in real-time control loops and metering front ends.
Typical applications include utility metering with local LCD displays, battery-powered handheld instruments, industrial control panels, and white-goods human-machine interfaces where the integrated LCD driver and 54 I/O lines eliminate a discrete LCD driver IC.
Design consideration: at 20 MHz and 5.5 V the supply current is highest; use the power-reduction register to clock-gate unused peripherals and consider the ATMEGA329PA-AU (picoPower) if battery life below a few microamps is required in sleep.
This page synthesizes distributor pricing, verified drop-in alternatives within the ATmega LCD family, and practical design notes not consolidated in the manufacturer datasheet.
Alternatives de remplacement direct pour ATMEGA329A-AU — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec ATMEGA329A-AU (même facteur de forme et même empreinte) — différant par Package, LCD Controller, Instructions, EEPROM, Core Architecture.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
ATMEGA329PA-AU
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATMEGA329P-AU
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATMEGA329-16AU
✅ Remplacement direct✓ En stock
$8.45 / unité
Voir la fiche technique →ATMEGA3290A-AU
✅ Remplacement direct✓ En stock
$3.85 / unité
Voir la fiche technique →ATMEGA325A-AU
✅ Remplacement direct✓ En stock
$3.12 / unité
Voir la fiche technique →ATMEGA329A-AU Valeurs maximales et caractéristiques électriques
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 32 KB ISP Flash (16K x 16) with read-while-write |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Fréquence d'horloge maximale | 20 MHz |
| General Purpose I/O | 54 lines |
| Working Registers | 32 general purpose |
| LCD Controller | On-chip LCD controller with internal contrast control |
| Debug/Programming Interface | JTAG (boundary-scan, on-chip debug, ISP programming) |
| Timers | Three flexible timers |
| Boîtier | 64-TQFP (14x14 mm) |
| Type de montage | Surface Mount |
| Temperature Grade | Industrial |
| Statut RoHS | Green (compliant) |
| Supply Voltage Range | 2.5 V to 5.5 V (per ATmega329A family; see datasheet) |
| Product Family | AVR ATmega |
Guide de configuration des broches du ATMEGA329A-AU 64-tqfp (14x14 mm)
Configuration des broches du ATMEGA329A-AU (boîtier 64-tqfp (14x14 mm)). Ce circuit intégré numérique comprend des GPIO, des interfaces de communication (UART, SPI, I2C) et des broches d'alimentation. Consultez la fiche technique du fabricant pour les fonctions alternatives des broches et les options de configuration. Indispensable pour la conception de systèmes embarqués et la conception de circuits imprimés.
Aucune donnée de brochage détaillée disponible pour ATMEGA329A-AU.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
ATMEGA329A-AU convient pour 6 applications: Utility Metering with LCD Display, Battery-Powered Handheld Instruments, Industrial Control Panels and HMI, White Goods and Appliance HMI, IoT Sensor Nodes with Local Display, Automotive and Industrial Sub-Assembly Controllers (Non-Safety).
Utility Metering with LCD Display
Electricity, water, and gas meters are the classic home of the ATMEGA329A-AU because the integrated LCD controller with internal contrast control drives segment glass directly, eliminating a standalone LCD driver IC and its routing overhead. The 54 GPIO lines cover keypad scanning, pulse inputs, and valve or relay control, while the 10-bit ADC samples analog measurement channels. Firmware fits comfortably in the 32 KB Flash with 2 KB SRAM for tariffing logic. The three flexible timers handle metering pulse capture and real-time tick generation. Designers should clock-gate unused peripherals via the power-reduction registers to meet regulatory standby budgets, or drop in the pin-compatible ATMEGA329PA-AU when sleep current below a few microamps is required.
Recommandé
Battery-Powered Handheld Instruments
Handheld test and measurement tools benefit from the ATmega329A's single-cycle RISC core, giving deterministic timing for measurement sequencing, plus the on-chip LCD for user readout without an external driver. Running at 20 MHz provides nearly 20 MIPS of throughput for DSP-lite filtering on the 10-bit ADC channels, while power-reduction registers allow rapid clock gating between samples. The 1 KB EEPROM stores calibration constants across battery replacement, and JTAG enables field debug during development. For instruments targeting multi-year battery life, select the picoPower ATMEGA329PA-AU instead, which is pin-to-pin compatible in the same 64-TQFP footprint and lowers both active and sleep current, so no PCB change is required to trade the upgrade.
Recommandé
Industrial Control Panels and HMI
Control panels need many I/O, robust timers, and a simple display; the ATMEGA329A-AU supplies 54 GPIO lines and an on-chip LCD controller in one 64-TQFP package, replacing what would otherwise require an MCU plus LCD driver chip pair. The industrial temperature grade suits unconditioned factory environments, and the green/RoHS-compliant package simplifies compliance paperwork for industrial customers. Three flexible timers generate PWM outputs for actuators and capture encoder or flow-meter inputs. The USART links to SCADA or PLC gateways over RS-485 with an external transceiver. Interrupt-driven design is straightforward thanks to the AVR's short, deterministic interrupt latency, keeping relay sequencing timing predictable across the full industrial temperature range.
Recommandé
White Goods and Appliance HMI
Washing machines, ovens, and climate appliances use segment LCDs, keypad inputs, and relay or triac control - precisely the peripheral mix of the ATmega329A. The LCD controller's internal contrast control adapts the display across viewing angles and temperature without extra bias circuitry, and the 32 general-purpose working registers keep interrupt service routines short when scanning keys and updating display segments concurrently. Flash read-while-write lets the appliance store last-used settings or fault logs into the 1 KB EEPROM between wash cycles. The device's ISP Flash capability allows final firmware personalization at the appliance factory through the JTAG or SPI interface, simplifying manufacturing without pre-programmed stock risk.
Recommandé
IoT Sensor Nodes with Local Display
Smart sensor nodes that show readings locally pair the ATmega329A's 10-bit ADC and LCD controller with an external radio module over SPI or UART. The AVR core handles sensor averaging and display refresh while sleeping between conversions, and the power-reduction register set clocks down unused peripherals to stretch battery life. The 2 KB SRAM buffers modest data bursts before transmission, and the EEPROM stores node ID and calibration. For nodes that must meet strict energy budgets, swap in the pin-compatible ATMEGA329PA-AU picoPower device on the same 64-TQFP footprint; for nodes with no display, the ATMEGA325A-AU recovers the LCD pins as GPIO for additional sensors at the same board cost.
Recommandé
Automotive and Industrial Sub-Assembly Controllers (Non-Safety)
Non-safety sub-assemblies such as seat controllers, lighting modules, and climate flaps need moderate compute, many I/O, and occasionally a small LCD or status display. The ATmega329A's 54 GPIO, three timers with PWM, and 20 MHz headroom cover flap motor sequencing and bulb diagnostics, while the JTAG boundary-scan capability supports in-circuit ICT during production - a practical benefit when panel test coverage is required. Note that this commercial/industrial-grade part is not AEC-Q100 qualified; for genuine automotive-grade requirements, evaluate Microchip's automotive-qualified AVR alternatives instead. The USART supports LIN-style media with an external transceiver for communication with the vehicle body controller.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour ATMEGA329A-AU — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | ATMEGA329PA-AU | ATMEGA329P-AU | ATMEGA329-16AU | ATMEGA325A-AU |
|---|---|---|---|---|---|
| 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 |
| Flash Memory | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 16 MHz | 20 MHz |
| On-chip LCD Controller | Yes (with internal contrast control) | Yes | Yes | Yes | No |
| Power Technology | Standard ATmega (A) | picoPower (lowest sleep current) | picoPower | Standard | Standard |
| SRAM / EEPROM | 2 KB / 1 KB | 2 KB / 1 KB | 2 KB / 1 KB | 2 KB / 1 KB | 2 KB / 1 KB |
| JTAG Debug/Programming | Yes (boundary-scan, OCD, ISP) | Yes | Yes | Yes | Yes |
Principaux différenciateurs
- On-chip LCD controller with internal contrast control (vs ATMEGA325A-AU)
- 20 MHz maximum clock (20 MIPS class throughput) (vs ATMEGA329-16AU)
- Trade-off: standard power vs picoPower sleep currents (vs ATMEGA329PA-AU)
- JTAG boundary-scan for production test (vs ATMEGA329PA-AU)
Notes de conception
Use the AVR power-reduction register to clock-gate the LCD controller, ADC, timers, and USART when idle; on the ATmega329A family each disabled peripheral removes its clock-tree consumption from the supply budget. For designs targeting sub-5 uA sleep, evaluate the pin-compatible ATMEGA329PA-AU picoPower part instead - it is footprint-identical in 64-TQFP so the change is a pure BOM swap. Estimated: supply current scales roughly linearly with clock frequency, so halving the system clock from 20 MHz to 10 MHz approximately halves active-mode current.
Decouple VCC and AVCC independently with 100 nF ceramic capacitors placed as close to each pin pair as possible, plus one bulk 4.7-10 uF per supply rail. Keep the analog supply (AVCC) clean by filtering from VCC with an LC or RC network when the ADC is used, and route LCD backplane/segment traces away from the crystal and analog front end. Provide JTAG header access (TCK, TMS, TDO, TDI) during development even if disabled in production to preserve debuggability.
Two frequent mistakes with this part: first, assuming the JTAG pins (shared with Port C) are available as GPIO - JTAG must be disabled via fuse programming after production programming, or those I/O lines will not function as intended. Second, replacing with ATMEGA325A-AU expecting a cheaper drop-in: the 325A has no LCD controller, so any existing display firmware will fail. Also verify clock-speed requirements before substituting ATMEGA329-16AU, which caps at 16 MHz rather than 20 MHz.
Estimated: at 20 MHz, 5.5 V, and full GPIO sourcing, an ATmega MCU typically dissipates well under 200 mW, which the 64-TQFP (14x14 mm) package dissipates with a standard SMD land pattern on a 2-layer PCB without a heatsink. Power dissipation is rarely the constraint on this device; the practical limit is total GPIO source/sink current per port, so respect the datasheet per-port and total device current limits when driving LEDs or relays directly.
Informations de conformité
Distributor listings describe the part as 'Green' (Microchip green package designation), indicating RoHS compliance and lead-free finish. No AEC-Q100 qualification is documented for this commercial/industrial grade part.