ATMEGA329A-MUR - 8-bit AVR MCU, 32KB Flash, 64-QFN | Microchip
MPN: ATMEGA329A-MUR ✓ Hoạt độngATMEGA329A-MUR Tóm tắt
What is an AVR microcontroller? An AVR is a family of 8-bit RISC microcontrollers originally developed by Atmel (now part of Microchip Technology) that use a modified Harvard architecture with separate program and data buses. In the broader taxonomy, the ATmega329A sits within: microcontroller -> embedded MCU -> 8-bit MCU -> AVR ATmega family -> LCD-display ATmega subfamily (the "329" series integrates an on-chip LCD driver). MCUs of this class are widely used in low-power, deterministic, interrupt-driven embedded designs where ease of programming and a rich peripheral set outweigh the need for raw CPU throughput.
Key features include 131 powerful instructions, mostly single-cycle execution (so 1 MIPS per MHz), 32 KB Flash organized as 16K x 16, 2 KB SRAM, and 1 KB on-chip EEPROM for non-volatile user data. On-chip peripherals include a segmented LCD driver, a 10-bit ADC, multiple timers/counters (8-bit and 16-bit), a USART, an SPI interface, and a TWI (I2C-compatible) bus. The device supports six software-selectable power-saving modes, with typical active current of a few mA at full speed and sub-microamp currents in Power-Down.
Architecturally, the ATmega329A uses a pipelined RISC core with 32 general-purpose working registers directly connected to the ALU, eliminating the accumulator bottleneck common to older 8-bit designs. This, combined with the on-chip LCD controller, makes it a particularly good fit for character or segment LCD-based products (POS terminals, metering, medical instruments, white goods) where the system needs to drive a glass directly without an external LCD controller.
Typical applications include battery-powered metering equipment with LCD readouts, handheld measurement instruments, white-goods and appliance user interfaces, point-of-sale terminals, low-end industrial HMIs, and sensor-conditioning front-ends. The on-chip segmented display driver is the primary differentiator over general-purpose ATmega parts that lack LCD support.
When designing with this part, allocate the bottom-layer PCB ground plane directly under the exposed pad of the 64-QFN and stitch multiple thermal vias into it; the pad is the primary heat-dissipation path and the only reliable ground reference for the inner-row balls. Verify pinout against revision-specific documentation because the ATmega329 and ATmega329A silicon differ in signature and a small number of register behaviors.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho ATMEGA329A-MUR — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với ATMEGA329A-MUR (cùng hình factor và footprint) — khác nhau ở Package, ADC, RoHS Status, Operating Temperature, LCD Controller.
ATMEGA329-16AUR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA329-16AU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA3290PV-10AUR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA3290V-8AUR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA325PA-MUR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA329A-MUR Tỷ lệ tối đa & tính chất điện
| Core Architecture | 8-bit AVR RISC |
| Program Memory (Flash) | 32 KB (16K x 16) |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Maximum CPU Speed | 20 MHz |
| Supply Voltage (Vcc) | 4.5 V to 5.5 V |
| I/O Pins | 32 |
| Hộp | 64-pin QFN (9 x 9 mm) with exposed pad |
| On-chip LCD Driver | Yes (segmented LCD) |
| ADC | 10-bit |
| Communication | USART, SPI, TWI (I2C-compatible) |
| Timers/Counters | 2 x 8-bit, 1 x 16-bit |
| Nhiệt độ hoạt động | -40 C to +85 C (Industrial) |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant ("Green") |
| Instruction Set | 131 instructions, mostly single-cycle |
Cấu hình chân ATMEGA329A-MUR
| Chân 1 | AVCC — Analog supply voltage |
| Chân 2 | AREF — Analog reference voltage |
| Chân 3 | GND — Analog ground |
| Chân 4 | PA0 — Port A bit 0 |
| Chân 5 | PA1 — Port A bit 1 |
| Chân 6 | PA2 — Port A bit 2 |
| Chân 7 | PA3 — Port A bit 3 |
| Chân 8 | PA4 — Port A bit 4 |
| Chân 9 | PA5 — Port A bit 5 |
| Chân 10 | PA6 — Port A bit 6 |
| Chân 11 | PA7 — Port A bit 7 |
| Chân 12 | VCC — Digital supply voltage |
| Chân 13 | GND — Digital ground |
| Chân 14 | PB0 — Port B bit 0 |
| Chân 15 | PB1 — Port B bit 1 |
| Chân 16 | PB2 — Port B bit 2 (SPI SS) |
| Chân 17 | PB3 — Port B bit 3 (SPI MOSI) |
| Chân 18 | PB4 — Port B bit 4 (SPI MISO) |
| Chân 19 | PB5 — Port B bit 5 (SPI SCK) |
| Chân 20 | PB6 — Port B bit 6 (TOSC1) |
| Chân 21 | PB7 — Port B bit 7 (TOSC2) |
| Chân 22 | PC0 — Port C bit 0 |
| Chân 23 | PC1 — Port C bit 1 |
| Chân 24 | PC2 — Port C bit 2 |
| Chân 25 | PC3 — Port C bit 3 |
| Chân 26 | PC4 — Port C bit 4 |
| Chân 27 | PC5 — Port C bit 5 |
| Chân 28 | PC6 — Port C bit 6 |
| Chân 29 | PC7 — Port C bit 7 |
| Chân 30 | PD0 — Port D bit 0 (LCD SEG) |
| Chân 31 | PD1 — Port D bit 1 (LCD SEG) |
| Chân 32 | PD2 — Port D bit 2 (LCD SEG) |
| Chân 33 | PD3 — Port D bit 3 (LCD SEG) |
| Chân 34 | PD4 — Port D bit 4 (LCD SEG) |
| Chân 35 | PD5 — Port D bit 5 (LCD SEG) |
| Chân 36 | PD6 — Port D bit 6 (LCD SEG) |
| Chân 37 | PD7 — Port D bit 7 (LCD SEG) |
| Chân 38 | PE0 — Port E bit 0 (LCD SEG/ COM) |
| Chân 39 | PE1 — Port E bit 1 (LCD SEG/ COM) |
| Chân 40 | PE2 — Port E bit 2 (LCD SEG/ COM) |
| Chân 41 | PE3 — Port E bit 3 (LCD SEG/ COM) |
| Chân 42 | PE4 — Port E bit 4 (LCD SEG/ COM) |
| Chân 43 | PE5 — Port E bit 5 (LCD SEG/ COM) |
| Chân 44 | PE6 — Port E bit 6 (LCD SEG/ COM) |
| Chân 45 | PE7 — Port E bit 7 (LCD SEG/ COM) |
| Chân 46 | PF0 — Port F bit 0 (LCD SEG) |
| Chân 47 | PF1 — Port F bit 1 (LCD SEG) |
| Chân 48 | PF2 — Port F bit 2 (LCD SEG) |
| Chân 49 | PF3 — Port F bit 3 (LCD SEG) |
| Chân 50 | PF4 — Port F bit 4 (LCD SEG) |
| Chân 51 | PF5 — Port F bit 5 (LCD SEG) |
| Chân 52 | PF6 — Port F bit 6 (LCD SEG) |
| Chân 53 | PF7 — Port F bit 7 (LCD SEG) |
| Chân 54 | VCC — Digital supply voltage |
| Chân 55 | GND — Digital ground |
| Chân 56 | XTAL2 — Crystal oscillator output |
| Chân 57 | XTAL1 — Crystal oscillator input |
| Chân 58 | RESET — Reset input (active low) |
| Chân 59 | VCC — Digital supply voltage |
| Chân 60 | GND — Digital ground |
| Chân 61 | LCDCAP — LCD charge pump capacitor |
| Chân 62 | LCDCAP — LCD charge pump capacitor |
| Chân 63 | NC — Not connected (per datasheet) |
| Chân 64 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
ATMEGA329A-MUR phù hợp cho 7 Áp dụngs: Battery-Powered Electricity Meter with LCD, Handheld Digital Multimeter, White-Goods Appliance User Interface, Point-of-Sale (POS) Terminal Keypad/Display Board, Industrial Sensor Conditioning Front-End, Medical Infusion Pump User Interface, Automotive Aftermarket Gauge Cluster.
Battery-Powered Electricity Meter with LCD
The ATMEGA329A-MUR is purpose-built for battery-powered metering because of its on-chip segmented LCD controller and six software-selectable sleep modes. In a typical single-phase electricity meter, the device drives a 4 x 25 segment LCD directly, samples current/voltage via its 10-bit ADC at low duty, and sleeps in Power-Down between updates, drawing microamp-level current while keeping the display live. The 32 KB Flash holds the metering firmware and calibration tables; the 1 KB EEPROM stores tamper logs and tariff parameters across battery swaps. Compared with using a general-purpose ATmega plus an external LCD driver, this part eliminates the external IC, lowers BOM cost, and reduces PCB area in sealed meter enclosures.
Được đề xuất
Handheld Digital Multimeter
In a handheld digital multimeter, the ATMEGA329A-MUR's 20 MHz core delivers 20 MIPS, enough to compute true-RMS conversions, autorange algorithms, and bar-graph LCD updates at 4 updates/second. Its 32 KB Flash accommodates calibration and lookup tables, while the 2 KB SRAM buffers sample sets without overflow. The integrated LCD driver connects directly to the multimeter's segment glass, removing the need for a separate HT1621-style controller and saving both cost and PCB real estate. Industrial temperature rating (-40 C to +85 C) lets the same part serve both indoor service tools and field-instrument variants.
Được đề xuất
White-Goods Appliance User Interface
Washing machines, dishwashers, and microwave ovens increasingly use segment LCDs or custom segment displays rather than discrete LEDs, and the ATMEGA329A-MUR is a strong fit for this user-interface role. Its on-chip LCD controller drives the segment glass directly, while the 32 GPIO handle rotary encoders, capacitive touch sense lines, and relay/triac drivers. Industrial temperature grade and 5 V operation match the harsh electrical environment of a switching-mode power supply. The 32 KB Flash supports multilingual menu fonts and diagnostic routines without external memory, and 1 KB EEPROM stores user preferences across power cycles.
Được đề xuất
Point-of-Sale (POS) Terminal Keypad/Display Board
In a POS terminal, the ATMEGA329A-MUR handles a segment customer-facing display and matrix keypad, communicating transaction events over SPI to a higher-end host processor. The 20 MHz core executes debouncing, encryption handoff, and display rendering with low latency. The integrated LCD driver removes the external HT1621 or PCF8576 typically needed, saving board area in the compact terminal housing. Operating from a regulated 5 V rail, the part coexists with the rest of the digital logic without level shifters, and its industrial temperature rating supports retail and light-industrial deployments.
Được đề xuất
Industrial Sensor Conditioning Front-End
The ATMEGA329A-MUR's 10-bit ADC, 32 GPIO, and TWI/SPI interfaces make it well suited as a low-cost front-end for industrial sensor signal conditioning and local display. The MCU can read 4-20 mA loop transmitters, thermocouples via an external amplifier, and digital local variables, drive a segment LCD to show process values, and forward data upstream via RS-485 or TWI to a PLC. Its 32 KB Flash hosts scaling, linearization, and fault-detection routines, while 1 KB EEPROM stores calibration constants. Compared with discrete analog front-ends, this single-chip solution reduces wiring and improves diagnostics visibility at the sensor head.
Được đề xuất
Medical Infusion Pump User Interface
Although not AEC-Q100 qualified, the ATMEGA329A-MUR's industrial temperature rating and on-chip LCD driver suit non-critical medical UI subassemblies such as infusion pump faceplates and bedside monitor keypads. The MCU drives a segment display showing infusion rate, volume, and alarm icons, scans a matrix keypad, and communicates with a safety-MCU host over SPI. Its 32 KB Flash supports multi-language strings, audible-alarm patterns, and self-test routines. Hardware CRC, watchdog timer, and brown-out detector built into the AVR core provide defense-in-depth for the UI subsystem without external components.
Được đề xuất
Automotive Aftermarket Gauge Cluster
In automotive aftermarket products such as boost gauges, oil-pressure readouts, and tachometer pods, the ATMEGA329A-MUR drives a small segment LCD that shows live readings while the engine runs. Although it is not AEC-Q100 qualified, designers commonly use industrial-grade AVR MCUs in this segment, and the integrated LCD controller removes the external HT1621-style driver typical in older designs. The 10-bit ADC reads 0-5 V sensor signals, the 16-bit timer captures RPM pulses, and SPI forwards data to a head unit for logging. Overkill cycles on Flash and EEPROM are sufficient for the long service life expected of these aftermarket products.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ATMEGA329A-MUR — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | ATMEGA329-16AUR | ATMEGA329-16AU | ATMEGA3290PV-10AUR | ATMEGA3290V-8AUR | ATMEGA325PA-MUR |
|---|---|---|---|---|---|---|
| Package | 64-QFN (9x9) | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB |
| SRAM | 2 KB | 2 KB | 2 KB | 4 KB | 4 KB | 1 KB |
| Max CPU Speed | 20 MHz | 16 MHz | 16 MHz | 10 MHz | 8 MHz | 20 MHz |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 4.5 V to 5.5 V |
| On-chip LCD Driver | Yes | Yes | Yes | Yes | Yes | Yes |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) |
Bảo phân biệt quan trọng
- Integrated segmented LCD controller eliminates external driver IC (vsATMEGA328P-MUR)
- Highest CPU speed in the LCD-display ATmega subfamily at this Flash density (vsATMEGA3290V-8AUR)
- Double the SRAM of the lower-memory ATmega325 sibling (vsATMEGA325PA-MUR)
Ghi chú thiết kế
The 64-QFN package has an exposed thermal pad on the underside that serves as the primary heat-dissipation path and the lowest-inductance ground reference for the inner-row balls. Solder this pad to a continuous top-layer ground pour and stitch at least 9 thermal vias (0.3 mm drill, 0.6 mm pad) into the inner ground plane. Forgetting to stitch vias raises junction temperature measurably and degrades ADC noise performance because the analog ground return becomes noisy.
AVCC must be tied to VCC through an LC filter (typically 10 uH inductor + 10 uF + 0.1 uF cap on AVCC) even if the ADC is unused; leaving AVCC floating produces high quiescent current and unreliable operation. AREF should be tied to a 0.1 uF capacitor when the internal reference is selected. The voltage on VCC should rise monotonically; if the rise time exceeds the datasheet's POR requirement, hold RESET low until VCC is stable.
Do not confuse ATmega329 with ATmega329A - the latter is a lower-power silicon revision. Device signature bytes differ, and some peripheral register behaviors are not identical. Programming tools and ISP code must target the correct signature. Also verify fuse settings: the default internal RC oscillator at 1 MHz is fine for bring-up but switch to an external crystal before ADC-sensitive measurements. Finally, the LCD driver charge-pump capacitor must be a low-leakage ceramic (C0G/NP0 preferred) - X7R is acceptable but watch for voltage coefficient at low drive levels.
Keep ADC traces short and away from the LCD segment lines, which toggle at the LCD frame frequency (typically 32-128 Hz). For best ADC SNR, use the largest practical conversion window and average multiple samples. The TWI (I2C) bus pins (PC0/PC1 on ATmega329A) require external pull-up resistors in the 2.2 kOhm to 10 kOhm range; the internal weak pull-ups are too weak for reliable communication above 100 kHz. SPI clock at the system 20 MHz core with F_CPU/2 divider is supported but verify that the slave device can keep up.
Thông tin tuân thủ
Per the verified web data, the part is supplied in 'Green' / lead-free / RoHS-compliant packaging. Microchip Technology publishes an official REACH statement and conflict-minerals declaration. Not AEC-Q100 qualified - the part is industrial-grade, not automotive-grade.
