ATMEGA649P-AUR - AVR 8-bit MCU 64KB Flash LCD | Microchip
MPN： ATMEGA649P-AUR ✓ 啟用中ATMEGA649P-AUR 概覽
An 8-bit AVR microcontroller (MCU) is a Harvard-architecture processor that executes most instructions in a single clock cycle, sitting within the broader hierarchy of embedded processors under microcontrollers, under the power- and cost-sensitive embedded systems category. The ATmega649P belongs to the ATmega LCD series (ATmega169A/PA/329A/PA/3290A/PA/649A/P/6490A/P family), which pairs general-purpose MCU peripherals with a segment LCD driver for glass-driving applications.
Key features include 54/69 general purpose I/O lines, 32 general purpose working registers, a JTAG interface for on-chip debug and boundary scan, and picoPower technology for ultra-low sleep-mode consumption. The P-suffix devices are drop-in replacements for the non-P ATmega649, produced on an improved process with lower power figures, and are subject to the same qualification and production test flow per Microchip application note AVR534.
The peripheral set includes an 8-bit timer/counter with PWM, a 16-bit timer/counter, SPI, USART, an analog comparator, a 10-bit ADC on related family members, and an LCD controller capable of driving segment glass directly - eliminating an external LCD driver IC in metering and appliance designs. ISP Flash with read-while-write allows firmware updates in the field without halting execution.
Typical applications include utility metering (energy and water meters with LCD displays), battery-powered handheld instruments, white-goods appliance panels, and industrial HMI front-ends where the integrated LCD driver and low sleep current extend battery life.
Design consideration: the picoPower benefits are realized only with correct sleep-mode selection (power-save or standby) and disabled unused peripherals; the 16MHz maximum CPU frequency is voltage-dependent, so derate clock speed at the low end of the supply range.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 ATMEGA649P-AUR — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： ATMEGA649P-AUR （相同外形與佔位） — 差異在於 Package, LCD Controller, Core Architecture, EEPROM, SRAM.
ATMEGA649A-AUR
✅ 直接替換聯絡詢價
查看資料表 →ATMEGA649P-16AUR
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
ATMEGA645P-AUR
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA645A-AUR
✅ 直接替換聯絡詢價
查看資料表 →ATMEGA329PA-AUR
✅ 直接替換聯絡詢價
查看資料表 →ATMEGA649P-AUR 最大額定值與電氣特性
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 64 KB ISP Flash (read-while-write) |
| EEPROM | 2 KB |
| SRAM | 4 KB |
| Maximum CPU Speed | 16 MHz |
| General Purpose I/O | 54/69 lines |
| Working Registers | 32 general purpose |
| LCD Controller | Integrated segment LCD driver |
| Debug Interface | JTAG (on-chip debug, boundary scan) |
| Low Power Technology | picoPower |
| 供應電壓 | 1.8 V to 5.5 V (picoPower family) |
| 工作溫度 | -40C to +85C (industrial, per A-grade suffix) |
| 封裝 | 64TQFP (TQFP-64) |
| 安裝類型 | Surface Mount |
| Packing | Tape & Reel (T&R) |
| RoHS / Green | GREEN package |
| Product Status | Active |
ATMEGA649P-AUR 64tqfp (tqfp-64) 腳位配置指南
ATMEGA649P-AUR（64tqfp (tqfp-64) 封裝）的腳位配置。 此數位 IC 包含 GPIO、通訊介面（UART、SPI、I2C）與電源腳位。替代腳位功能與配置選項請參閱製造商資料表。對嵌入式系統設計與 PCB 佈局至關重要。
無詳細腳位定義資料： ATMEGA649P-AUR.
請參閱 資料表 以查看完整腳位配置。
典型應用
ATMEGA649P-AUR 適用於 6 應用s: Utility Metering (Energy/Water Meters), Battery-Powered Handheld Instruments, Home Appliance Control Panels, Industrial HMI Front-Ends, Security and Access Control Keypads, Smart Home Sensor Nodes.
Utility Metering (Energy/Water Meters)
The ATMEGA649P-AUR fits electricity, water, and gas meters because the integrated segment LCD controller drives the display glass directly while picoPower sleep modes keep average battery current in the microamp range. A typical topology runs the AVR from a mains-derived or battery supply at 3.3V, pulses from the metrology front-end into a pin-change interrupt, and multiplexes the LCD in power-save mode. The 64KB Flash accommodates metering firmware plus communication stacks, and the 2KB EEPROM stores calibration and billing data through power cycles. The trade-off versus an MCU-plus-external-LCD-driver solution is fewer available I/O while the glass is connected, but BOM cost and board area drop noticeably.
推薦
Battery-Powered Handheld Instruments
Handheld gauges, testers, and diagnostic tools benefit from the ATMEGA649P-AUR's combination of a directly driven LCD, 1.8V-to-5.5V supply range, and picoPower low-power modes that stretch battery runtime between charges. The device typically sleeps in power-save with an RTC running on a 32kHz crystal, wakes on a key press or timer, and runs measurement code at 16MHz for fast response. SPI interfaces external ADCs or RF modules, while the USART handles PC connectivity. Because the LCD controller is on-chip, the display stays partially visible in low-power states - useful for showing status between measurements. Designers should derate clock speed at low battery voltage per the datasheet speed-versus-voltage curve to guarantee reliable operation near end-of-discharge.
推薦
Home Appliance Control Panels
White-goods and HVAC front panels use the ATMEGA649P-AUR to combine user-interface segment LCDs, touch or mechanical buttons, and actuator control in a single IC. The 54/69 general purpose I/O lines drive relays, triacs, fans, and buzzer outputs while the LCD controller runs the display glass, removing an external driver stage from the control board. The industrial -40C to +85C temperature rating tolerates kitchen and utility-room environments, and JTAG supports factory debug fixtures. ISP Flash with read-while-write enables production-line firmware updates without socketing parts. The 16MHz AVR core executes single-cycle instructions, giving responsive button debouncing and display refresh even with modest clock rates that also reduce EMI on the appliance's shared ground.
推薦
Industrial HMI Front-Ends
Machine-mounted operator interfaces leverage the ATMEGA649P-AUR's segment LCD, generous I/O count, and JTAG boundary scan for panel-level manufacturing test. In a typical design the MCU scans keypad matrices, drives status glass, and communicates with a main controller over SPI or USART, while the industrial temperature grade handles cabinet environments from -40C to +85C. The 64KB ISP Flash leaves room for protocol handling plus localized logic, and the 4KB SRAM buffers message queues without external RAM. Boundary-scan via JTAG shortens ICT fixture development on multi-board panels. Compared with a graphics-TFT solution, the segment-LCD approach costs less and draws far less power, at the trade-off of fixed annunciator layouts rather than freely drawn graphics.
推薦
Security and Access Control Keypads
Door controllers and alarm keypads exploit the ATMEGA649P-AUR's LCD, low sleep current, and EEPROM for credential and configuration storage. The picoPower architecture keeps standby drain low on battery-backup systems, waking on keypad interrupts or WDT periodic checks; the 16MHz core handles DES/AES-lite key checks and RS-485 framing in software. Segment LCDs show arm/disarm status, zone count, and diagnostics without the cost of a graphics display. The 2KB EEPROM retains user codes through power loss with sufficient endurance for frequent code changes, and the 64KB Flash hosts logging plus communication firmware. Developers should budget SRAM carefully - 4KB is adequate for framed protocols but not for TLS-class stacks, which may require an offloaded companion controller.
推薦
Smart Home Sensor Nodes
Zigbee-adjacent and proprietary-protocol smart-home nodes use the ATMEGA649P-AUR as the sensor controller with a small segment LCD for local indication, a combination few 8-bit MCUs offer in one package. PicoPower sleep modes let a temperature or occupancy node idle in the microamp region and wake on sensor thresholds, transmitting via a SPI radio module. The 1.8V supply floor allows direct two-cell battery operation, avoiding a boost converter, while 54/69 I/O lines cover multiple sensor buses and status LEDs. The 64KB Flash supports OTA-style bootloader code alongside the application, and EEPROM stores calibration and network addresses. The engineering trade-off: commission a bootloader carefully since 4KB SRAM constrains buffer-heavy radio stacks.
推薦
推薦產品摘要
工程參考資料，適用於 ATMEGA649P-AUR — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | ATMEGA649A-AUR | ATMEGA645P-AUR | ATMEGA645A-AUR | ATMEGA329PA-AUR |
|---|---|---|---|---|---|
| Package | TQFP-64 | TQFP-64 - same | TQFP-64 - same | TQFP-64 - same | TQFP-64 - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 32 KB |
| EEPROM | 2 KB | 2 KB | 2 KB | 2 KB | 1 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 2 KB |
| Max CPU Speed | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 20 MHz |
| LCD Controller | Yes (integrated segment LCD) | Yes | Yes | Yes | Yes |
| Low Power Process | picoPower (P variant) | Standard (non-P) | picoPower (P variant) | Standard (non-P) | picoPower (P variant) |
主要差異化特點
- picoPower low-sleep-current process (對比ATMEGA649A-AUR)
- Same memory footprint at the same price point with drop-in migration (對比ATMEGA645A-AUR)
- Double the code space of the low-cost LCD alternative (對比ATMEGA329PA-AUR)
設計說明
To realize the picoPower benefit, actively manage sleep modes: enter power-save or standby rather than idle, disable the analog comparator and unused timer clocks via the PRR register, and use pin-change or watchdog interrupts for wake. The 16MHz maximum frequency is voltage-dependent - verify the datasheet speed-versus-voltage curve before running full speed at low battery voltage. Estimated: a node sleeping 99% of the time in power-save with the LCD in static mode can reduce average current by more than an order of magnitude versus running idle, directly extending coin-cell or Li-SOCl2 battery life in metering products.
Decouple every VCC/AVCC pin pair with 100nF ceramics placed within a few millimeters of the pins, with at least one bulk 4.7-10uF capacitor per supply rail. Keep the LCD driving traces (segment/common lines routed to the glass) reasonably balanced in length and away from the SPI/USART lines to minimize display ghosting and crosstalk. The TQFP-64 thermal pad requirement is modest for this power class, but a solid ground plane under the part improves LCD common-signal quality. Connect the JTAG header (TDI/TDO/TMS/TCK plus reset) on production boards for field debug and boundary-scan ICT.
Do not treat the P variant and non-P variant as electrically identical in power budget calculations: Microchip application note AVR534 states the ATmega649P is an upwards-compatible drop-in for the ATmega649, but some electrical characteristics differ. Re-verify sleep currents and threshold voltages when migrating between ATMEGA649A and ATMEGA649P. Also confirm that port pins shared with LCD segment functions are not double-assigned in your pinout tool - LCD alternate functions vary across the ATmega329/649/6490 family members, and accidental conflicts cause phantom segments.
合規資訊
Distributor listings describe the part as GREEN (RoHS/lead-free) with Tape & Reel packing. REACH, halogen-free and conflict-minerals status not stated in retrieved data.
