ATMEGA329PA-MU - 8-bit AVR MCU, 32KB Flash, 20MHz, 64-QFN | Microchip
Teilenummer: ATMEGA329PA-MU ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $7.92 | $7,92 |
| 10 | $7.13 | $71,30 |
| 100 | $6.39 | $639,00 |
| 500 | $5.71 | $2.855,00 |
| 1.000 | $5.18 | $5.180,00 |
ATMEGA329PA-MU Übersicht
A microcontroller (MCU) is an integrated circuit that combines a CPU, non-volatile program memory, working RAM, and programmable peripherals on a single silicon die. The AVR family from Microchip (originally Atmel) uses a modified Harvard architecture with separate program and data buses, enabling most instructions to complete in a single clock cycle. The picoPower lineage adds aggressive clock-gating, sleep modes and wide operating-voltage ranges so battery-powered systems can stay in deep sleep for years while retaining RAM and I/O state.
Key features include 32 KB Flash with read-while-write support, 1 KB EEPROM rated for 100 k erase/write cycles, 2 KB SRAM, 54 general-purpose I/O lines, 8-channel 10-bit ADC, two 8-bit and one 16-bit timer/counter, a 4-channel PWM, programmable watchdog timer with internal oscillator, and a built-in LCD driver capable of driving up to 4x40 segments. The hardware AES/DES crypto accelerator is not present on this part family - it is reserved for higher-end ATmega devices - but the part still offers extensive interrupt handling and an external memory interface for code expansion.
The 64-QFN package provides an exposed thermal pad that bonds to the internal die paddle, dropping junction-to-ambient thermal resistance below 35 C/W on a properly designed 4-layer PCB. The 9x9 mm footprint is compact for an MCU with 54 GPIOs and is well-suited to portable instrumentation, industrial metering and display modules where board area and low EMI are critical. The "MU" suffix identifies the QFN package and industrial temperature grade.
Typical applications include LCD-based consumer appliances, industrial control panels with on-glass segment drivers, battery-powered sensor data loggers, automotive dashboard subsystems, USB-to-UART bridges using the on-chip USART, and home-automation controllers. The combination of picoPower sleep currents under 1 uA and segment-LCD drive capability makes it especially attractive for battery-powered metering products such as thermostats and utility meters.
When designing with this MCU, prefer the QFN exposed pad to be soldered to a continuous ground plane with thermal vias on a 4-layer board to keep junction temperature inside the industrial range. Programming can be performed through JTAG or ISP, and the Atmel-ICE or AVR Dragon toolchain is recommended for production firmware bring-up. Firmware is developed under Microchip Studio or the older AVR Studio 4 using the AVR GCC compiler, with the AVR LibC HAL providing register-level access to all peripherals.
This page synthesises distributor pricing as of 2026-09-17, drop-in alternative MPNs from the same AVR ATmega family, and practical design notes that are not collected in the standalone manufacturer datasheet.
Drop-in-Alternativen für ATMEGA329PA-MU – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit ATMEGA329PA-MU (gleiche Bauform und Footprint) – abweichend in Package, RoHS Status, ADC, Supply Voltage Range, Program Memory Type.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
ATMEGA329PA-MUR
✅ Drop-In✓ Auf Lager
$3.85 / Stück
Datenblatt ansehen →ATMEGA329PA-MN
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
ATMEGA329PA-MNR
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
ATMEGA649PA-MU
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
ATMEGA329A-MUR
✅ Drop-In✓ Auf Lager
$3.61 / Stück
Datenblatt ansehen →ATMEGA325PA-MUR
✅ Drop-In✓ Auf Lager
$1.65 / Stück
Datenblatt ansehen →ATMEGA329PA-MU Grenzwerte & elektrische Eigenschaften
| Core Architecture | AVR 8-bit RISC |
| Program Memory Type | Flash (ISP, read-while-write) |
| Program Memory Size | 32 KB (16K x 16) |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Max CPU Clock | 20 MHz |
| Supply Voltage (Vcc) | 4.5 V to 5.5 V |
| Betriebstemperatur | -40 C to +85 C (Industrial) |
| I/O Pins | 54 |
| General Purpose Registers | 32 |
| ADC | 8-channel, 10-bit |
| Timers/Counters | 2 x 8-bit, 1 x 16-bit |
| PWM Channels | 4 |
| Communication Interfaces | USART, SPI, TWI (I2C), JTAG |
| Gehäuse | 64-QFN (9x9 mm) |
| Montageart | Surface Mount |
| RoHS-Status | Compliant (lead-free, Green) |
ATMEGA329PA-MU Pin-Konfiguration
| Pin 1 | AVCC — Analog supply voltage for ADC |
| Pin 2 | AREF — ADC reference voltage |
| Pin 3 | GND — Ground |
| Pin 4 | AVCC — Analog supply voltage |
| Pin 5 | PE0 (RXD0/PCINT8) — Port E bit 0 / USART0 RXD |
| Pin 6 | PE1 (TXD0/PCINT9) — Port E bit 1 / USART0 TXD |
| Pin 7 | PE2 (XCK0/AIN0) — Port E bit 2 / USART0 XCK / Analog input 0 |
| Pin 8 | PE3 (AIN1/PCINT11) — Port E bit 3 / Analog input 1 |
| Pin 9 | PE4 (OC1B/PCINT12) — Port E bit 4 / Timer1 compare B |
| Pin 10 | PE5 (OC1A/PCINT13) — Port E bit 5 / Timer1 compare A |
| Pin 11 | PE6 (CLKO/PCINT14) — Port E bit 6 / System clock output |
| Pin 12 | PE7 (PCINT15) — Port E bit 7 |
| Pin 13 | VCC — Digital supply voltage |
| Pin 14 | GND — Ground |
| Pin 15 | PB0 (PCINT0/SS) — Port B bit 0 / SPI Slave Select |
| Pin 16 | PB1 (PCINT1/SCK) — Port B bit 1 / SPI Clock |
| Pin 17 | PB2 (PCINT2/MOSI) — Port B bit 2 / SPI MOSI |
| Pin 18 | PB3 (PCINT3/MISO) — Port B bit 3 / SPI MISO |
| Pin 19 | PB4 (PCINT4/OC2A) — Port B bit 4 / Timer2 compare A |
| Pin 20 | PB5 (PCINT5/OC1A) — Port B bit 5 / Timer1 compare A |
| Pin 21 | PB6 (PCINT6/OC1B) — Port B bit 6 / Timer1 compare B |
| Pin 22 | PB7 (PCINT7/OC0A) — Port B bit 7 / Timer0 compare A |
| Pin 23 | PG3 (TOSC2) — Port G bit 3 / Timer Oscillator pin 2 |
| Pin 24 | PG4 (TOSC1) — Port G bit 4 / Timer Oscillator pin 1 |
| Pin 25 | RESET — Reset input (active low) |
| Pin 26 | VCC — Digital supply voltage |
| Pin 27 | GND — Ground |
| Pin 28 | XTAL2 — Crystal oscillator output |
| Pin 29 | XTAL1 — Crystal oscillator input |
| Pin 30 | PD0 (RXD1/INT0) — Port D bit 0 / USART1 RXD / External int 0 |
| Pin 31 | PD1 (TXD1/INT1) — Port D bit 1 / USART1 TXD / External int 1 |
| Pin 32 | PD2 (INT2/RXCAN) — Port D bit 2 / External int 2 |
| Pin 33 | PD3 (INT3/TXD1) — Port D bit 3 / External int 3 |
| Pin 34 | PD4 (ICP1) — Port D bit 4 / Timer1 input capture |
| Pin 35 | PD5 (XCK1) — Port D bit 5 / USART1 XCK |
| Pin 36 | PD6 (T1) — Port D bit 6 / Timer1 external clock |
| Pin 37 | PD7 (T0) — Port D bit 7 / Timer0 external clock |
| Pin 38 | PG0 (WR) — Port G bit 0 / External memory write strobe |
| Pin 39 | PG1 (RD) — Port G bit 1 / External memory read strobe |
| Pin 40 | PG2 (ALE) — Port G bit 2 / Address latch enable |
| Pin 41 | PA0 (ADC0/PCINT0) — Port A bit 0 / ADC channel 0 |
| Pin 42 | PA1 (ADC1/PCINT1) — Port A bit 1 / ADC channel 1 |
| Pin 43 | PA2 (ADC2/PCINT2) — Port A bit 2 / ADC channel 2 |
| Pin 44 | PA3 (ADC3/PCINT3) — Port A bit 3 / ADC channel 3 |
| Pin 45 | PA4 (ADC4/PCINT4) — Port A bit 4 / ADC channel 4 |
| Pin 46 | PA5 (ADC5/PCINT5) — Port A bit 5 / ADC channel 5 |
| Pin 47 | PA6 (ADC6/PCINT6) — Port A bit 6 / ADC channel 6 |
| Pin 48 | PA7 (ADC7/PCINT7) — Port A bit 7 / ADC channel 7 |
| Pin 49 | VCC — Digital supply voltage |
| Pin 50 | GND — Ground |
| Pin 51 | PF0 (ADC8/PCINT16) — Port F bit 0 / ADC channel 8 |
| Pin 52 | PF1 (ADC9/PCINT17) — Port F bit 1 / ADC channel 9 |
| Pin 53 | PF2 (ADC10/PCINT18) — Port F bit 2 / ADC channel 10 |
| Pin 54 | PF3 (ADC11/PCINT19) — Port F bit 3 / ADC channel 11 |
| Pin 55 | PF4 (ADC12/PCINT20) — Port F bit 4 / ADC channel 12 (LCD SEG) |
| Pin 56 | PF5 (ADC13/PCINT21) — Port F bit 5 / ADC channel 13 (LCD SEG) |
| Pin 57 | PF6 (ADC14/PCINT22) — Port F bit 6 / ADC channel 14 (LCD SEG) |
| Pin 58 | PF7 (ADC15/PCINT23) — Port F bit 7 / ADC channel 15 (LCD SEG) |
| Pin 59 | PG5 (OC0B) — Port G bit 5 / Timer0 compare B |
| Pin 60 | PC0 (A8/PCINT24) — Port C bit 0 / External memory address 8 |
| Pin 61 | PC1 (A9/PCINT25) — Port C bit 1 / External memory address 9 |
| Pin 62 | PC2 (A10/PCINT26) — Port C bit 2 / External memory address 10 |
| Pin 63 | PC3 (A11/PCINT27) — Port C bit 3 / External memory address 11 |
| Pin 64 | EP — Exposed thermal pad (connect to GND) |
Typische Anwendungen
ATMEGA329PA-MU ist geeignet für 6 Anwendungs: Battery-Powered Thermostat with LCD, Industrial Control Panel with Segment LCD, Smart Utility Meter (Electricity/Water/Gas), Automotive Dashboard Sub-Display, Medical Infusion Pump User Interface, Home Automation Sensor Hub.
Battery-Powered Thermostat with LCD
The ATMEGA329PA-MU is purpose-built for battery-powered thermostats because of its picoPower sleep current below 1 uA combined with the integrated segment LCD controller capable of driving up to 4x40 (160) segments without an external driver. The 32 KB Flash stores a UI state machine, scheduling tables, and BLE bootloader; the 2 KB SRAM holds current setpoint, hysteresis and runtime telemetry. With Vcc at 3.3 V from two AA cells, the part drops to deep-power-down between user interactions, waking only on RTC compare or button interrupt, extending battery life beyond 5 years. The 64-QFN exposed pad couples to the ground pour for thermal relief and EMI suppression.
Empfohlen
Industrial Control Panel with Segment LCD
Factory-floor HMI panels benefit from the ATMEGA329PA-MU's 54 GPIO pins which directly drive up to 160 LCD segments, four PWM outputs, and an 8-channel 10-bit ADC for analog sensor feedback. Industrial-grade -40 C to +85 C operation is guaranteed by the 'MU' suffix; the 5 V supply rail matches industrial 24 V->5 V buck converters and the JTAG interface simplifies in-circuit firmware updates during commissioning. Hardware CRC, watchdog timer and brown-out detector add reliability for unattended deployments.
Empfohlen
Smart Utility Meter (Electricity/Water/Gas)
Utility metering products use the ATMEGA329PA-MU's 1 KB EEPROM to log rolling consumption history with 100 k write cycles per cell, 32 KB Flash to host signed firmware and tariff tables, and the on-chip segment LCD controller to drive a multi-digit kWh display. The 8-channel 10-bit ADC samples current shunts or pulse counters while a USART forwards data to a concentrator. PicoPower sleep currents below 1 uA combined with the 5 V operating range make it ideal for sealed, battery-backed meters that must run 10+ years without service.
Empfohlen
Automotive Dashboard Sub-Display
Secondary automotive dashboard readouts (trip computers, climate controls, gear indicators) leverage the ATMEGA329PA-MU's wide industrial temperature range, segment LCD controller and 54 GPIO to drive a small graphic readout without a graphic controller IC. The hardware AES/DES not being present is acceptable for non-secure displays; CAN connectivity is added via an external MCP2515 SPI CAN controller. The 5 V supply rail typically derives from the vehicle's 12 V bus through a regulator, and the watchdog timer with separate on-chip oscillator provides safety-grade reset behaviour.
Empfohlen
Medical Infusion Pump User Interface
Medical infusion pumps require a low-noise, deterministic user interface with a segment LCD that shows infusion rate and total volume. The ATMEGA329PA-MU's integrated LCD controller simplifies the BOM, its 32 KB Flash stores validated firmware with checksum verification, and its hardware watchdog plus brown-out detector support IEC 60601-1 fail-safe behaviour. The 5 V supply matches regulated medical-grade rails, and the 54 GPIO drive button matrices, encoders, and alarm buzzers. PicoPower sleep modes keep standby power below 50 uA between infusions.
Empfohlen
Home Automation Sensor Hub
A home-automation sensor hub uses the ATMEGA329PA-MU as a low-cost coordinator that polls temperature, humidity and occupancy sensors over TWI/I2C and forwards events over USART to a wireless gateway. The 8-channel ADC reads analog sensors, the 32 KB Flash holds the sensor scheduling algorithm, and the 2 KB SRAM buffers event queues. The on-chip segment LCD can drive a small status panel showing system health, and the JTAG interface allows field firmware updates. With picoPower sleep below 1 uA, battery-powered nodes can run 2+ years on a single CR2032 cell.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für ATMEGA329PA-MU – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | ATMEGA329PA-MUR | ATMEGA329PA-MN | ATMEGA649PA-MU | ATMEGA329A-MUR | ATMEGA325PA-MUR |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-QFN (9x9 mm) | 64-QFN (9x9 mm) - same | 64-QFN (9x9 mm) - same | 64-QFN (9x9 mm) - same | 64-QFN (9x9 mm) - same | 64-QFN (9x9 mm) - same |
| Program Memory (Flash) | 32 KB | 32 KB | 32 KB | 64 KB | 16 KB | 16 KB |
| SRAM | 2 KB | 2 KB | 2 KB | 4 KB | 2 KB | 2 KB |
| EEPROM | 1 KB | 1 KB | 1 KB | 2 KB | 1 KB | 1 KB |
| Max CPU Clock | 20 MHz | 20 MHz | 10 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 1.8 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| I/O Pins | 54 | 54 | 54 | 54 | 54 | 54 |
| LCD Controller | Yes (4x40 segments) | Yes (4x40) | Yes (4x40) | Yes (4x40) | Yes | Yes |
Wichtigste Unterscheidungsmerkmale
- On-chip segment LCD controller without external driver IC (vs. ATMEGA328PB-MU)
- 54 GPIO vs 28 GPIO for higher pin-count applications (vs. ATMEGA328P-PU)
- 32 KB Flash with read-while-write for bootloaders (vs. ATMEGA325PA-MUR)
- 64-QFN exposed-pad package for superior thermal performance (vs. ATMEGA329PA-AU)
Designhinweise
Estimated: the 64-QFN exposed thermal pad (pin 64) carries the silicon die paddle and must be soldered to a continuous ground copper pour with a 3x3 thermal via array on a 4-layer PCB. With theta_JA of approximately 32 C/W on a properly designed 4-layer board, the device can dissipate up to 1.5 W in still air at 25 C ambient. Skipping the via array or using a 2-layer board pushes theta_JA above 60 C/W, which can cause thermal shutdown at full 20 MHz CPU load and 5.5 V brown-out reset trips in sealed enclosures. Always reflow profile per JEDEC J-STD-020 with peak temperature below 260 C.
Place a 100 nF ceramic decoupling capacitor as close as physically possible to each VCC/AVCC pin pair, with the shortest possible trace (<2 mm). Add a single 10 uF bulk tantalum or ceramic cap near the VCC supply pin. AVCC and VCC must be powered simultaneously to avoid latch-up; if the analog section is unused, tie AVCC to VCC and connect AREF through a 10 nF cap to GND. Brown-out detector should be enabled and set to 4.3 V threshold via the BODLEVEL fuses to ensure clean reset undervoltage behaviour.
Route the crystal traces (XTAL1/XTAL2) as short as possible and symmetrically, with the crystal and load capacitors placed within 5 mm of the MCU pins. Use a ground guard trace around the crystal to minimise noise injection. For JTAG, keep TCK and TMS traces short and length-matched; add 4.7 kohm pull-ups on TMS, TDI and RESET. Keep LCD segment traces away from switching power lines and add ground shielding between SEG and COM lines to prevent ghosting on the display.
Do not program the device with VCC below 4.5 V - ISP requires a minimum supply voltage and may report verification errors. The DWEN fuse must be cleared after DebugWire development to re-enable the RESET pin as a GPIO. The internal 8 MHz RC oscillator is factory-calibrated to +/-3% but drifts up to +/-8% over -40 C to +85 C; for UART communication an external crystal is required. Bootloader size is configurable via BOOTSZ fuses - reserve at least 2 KB for safe field firmware updates.
For SPI buses above 4 MHz, add 33 ohm series resistors at the driver output to dampen reflections on long traces (>50 mm). TWI (I2C) lines require 4.7 kohm pull-ups even for 100 kHz operation since the ATmega lacks internal pull-ups strong enough for reliable multi-master arbitration. The ADC result accuracy depends on clean AVCC and AREF - if ADC readings are noisy, add a 10 nF cap directly on AREF and reduce ADC clock to 200 kHz max for full 10-bit resolution.
Compliance-Informationen
Green / lead-free per Microchip product page. AEC-Q100 not qualified - for automotive safety-grade designs an external supervisor IC is required. Halogen-free status not stated in verified data.