ATMEGA649-16MU - 8-bit AVR MCU 64KB Flash 16MHz 64-QFN | Microchip
料号： ATMEGA649-16MU ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $7.94 | $7.94 |
| 10 | $7.15 | $71.50 |
| 100 | $6.2 | $620.00 |
| 500 | $5.4 | $2,700.00 |
| 1,000 | $4.8 | $4,800.00 |
ATMEGA649-16MU 概述
An 8-bit AVR microcontroller is a Harvard-architecture RISC processor executing most instructions in a single clock cycle. Within the power-management hierarchy, the ATmega family sits in the general-purpose MCU tier, spanning Flash densities from 4KB to 256KB, and the ATmega649 occupies the 64KB mid-range slot with a unique on-chip segment LCD driver.
Key features include 54/69 general purpose I/O lines, 32 general purpose working registers, a JTAG interface for boundary-scan and on-chip debugging/programming, and a complete on-chip LCD controller with internal contrast control. Read-while-write Flash capability allows firmware updates during execution, while ISP (In-System Programmable) Flash simplifies field upgrades without removing the device from the PCB.
Architecturally, the AVR core uses a single-cycle ALU fed by two register-file read ports, sustaining up to 16 MIPS at 16MHz. The LCD controller drives segmented glass directly with internal contrast control, eliminating an external LCD driver IC and its firmware overhead. Peripherals include flexible timers, USART, SPI, and an analog comparator with ADC per family datasheet.
Typical applications include battery-powered instruments with segment LCD displays, utility metering, industrial control panels, and hand-held measurement devices where the integrated LCD controller and low-power AVR core reduce system cost and board area.
A key design consideration: verify availability of the newer ATMEGA649A variant, which is designated as the newer device by the manufacturer, for new designs to maximize lifecycle headroom.
This page synthesizes distributor pricing from 12 sources, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替换替代料： ATMEGA649-16MU ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： ATMEGA649-16MU （相同外形与封装尺寸） ——差异在于 Package, Supply Voltage Range, ADC Channels, ADC Resolution, Debug Interface.
快速对比工具——选择替代料号进行并排对比：
ATMEGA649A-MU
✅ 直接替换✓ 有现货
$4.42 / 个
查看数据手册 →ATMEGA649V-8MUR
✅ 直接替换📋 参考替代料（不在目录中）
ATMEGA649-16MI
✅ 直接替换📋 参考替代料（不在目录中）
ATMEGA645-16MUR
✅ 直接替换✓ 有现货
$3.35 / 个
查看数据手册 →ATMEGA645-16MUR
✅ 直接替换✓ 有现货
$3.35 / 个
查看数据手册 →ATMEGA649-16MU 最大额定值与电气特性
| Core Processor | AVR |
| Core Size | 8-bit |
| Speed | 16 MHz |
| Flash Memory | 64 KB (32K x 16) |
| EEPROM | 2 KB |
| RAM | 4 KB |
| GPIO | 54 / 69 |
| Connectivity | SPI, UART/USART |
| LCD Controller | On-chip LCD controller with internal contrast control |
| JTAG | Yes (boundary-scan and on-chip debug/programming) |
| Oscillator Type | Internal |
| 封装 | 64-QFN (9x9 mm) with exposed pad (64-VFQFN) |
| 安装类型 | Surface Mount |
ATMEGA649-16MU 64-qfn (9x9 mm) with exposed pad (64-vfqfn) 引脚配置指南
ATMEGA649-16MU（64-qfn (9x9 mm) with exposed pad (64-vfqfn) 封装）的引脚配置。 该数字 IC 包含 GPIO、通信接口（UART、SPI、I2C）和电源引脚。请参阅制造商数据手册以了解复用引脚功能和配置选项。对嵌入式系统设计和 PCB 布局至关重要。
暂无详细引脚数据： ATMEGA649-16MU.
请参阅 数据手册 以查看完整引脚配置。
典型应用
ATMEGA649-16MU 适用于 6 应用s: Utility Metering, Industrial Control Panels, Hand-held Instruments, Building Automation Nodes, Consumer Appliance Displays, POS and Access Control Terminals.
Utility Metering
The ATMEGA649-16MU fits electricity, water, and gas meter designs because its on-chip LCD controller with internal contrast control drives segment glass directly, eliminating an external LCD driver IC and the I/O and firmware overhead it would consume. The 64KB ISP Flash with read-while-write capability allows field firmware updates that keep calibration tables in the 2KB EEPROM without interrupting measurement code. At 16MHz the AVR core delivers up to 16 MIPS, ample for accumulation algorithms and communication protocols over USART. Battery-backed designs benefit from the AVR's low-power modes; the exposed-pad 64-QFN improves thermal and ground integrity for the analog front end.
推荐
Industrial Control Panels
Industrial HMI panels and machine control boards benefit from the ATMEGA649-16MU's combination of 54/69 GPIO lines, on-chip LCD controller, and JTAG boundary-scan for board-level production test. The 16MHz single-cycle AVR core executes control loops and protocol handling efficiently, while 64KB Flash accommodates menus, fonts, and logging. SPI and USART interfaces connect to encoders, EEPROMs, and RS-485 transceivers. JTAG on-chip debugging shortens development cycles without additional debug silicon, and the 64-QFN exposed-pad package provides robust ground returns for electrically noisy factory environments. Designers should add supply supervision and TVS protection on field-facing I/O per standard practice.
推荐
Hand-held Instruments
Hand-held measurement and diagnostic instruments pair naturally with the ATMEGA649-16MU because the integrated LCD segment driver displays readings without a graphic display controller, keeping current draw and BOM cost low in battery operation. The 4KB SRAM supports data buffering and averaging routines, and the 2KB EEPROM stores calibration constants through power cycles. Single-cycle RISC execution at 16MHz gives responsive user interfaces, while the internal oscillator option reduces component count for compact layouts. The 9x9mm 64-QFN keeps PCB area small enough for pocket-size enclosures. Designers should budget button debouncing and backlight driver current separately from the MCU supply.
推荐
Building Automation Nodes
Sensor and actuator nodes in building automation use the ATMEGA649-16MU where a local LCD readout plus moderate I/O count is required, such as thermostat and zone-controller boards. Its SPI and USART interfaces link to transceivers and external memory, and the 64KB Flash leaves headroom for protocol stacks alongside application code. Read-while-write Flash lets the node log events or update firmware while control routines continue running. The AVR's low-power modes stretch battery life in wireless-retrofit scenarios, and JTAG simplifies production programming and boundary-scan test of densely populated node boards. Verify supply supervision timing to guarantee clean resets on brown-out-prone 24V-derived rails.
推荐
Consumer Appliance Displays
Ovens, laundry machines, and HVAC thermostats that show status on segment LCDs are classic ATmega649 applications: the on-chip LCD controller with internal contrast control handles the glass directly, and the 64-QFN's 69 GPIO option covers relays, keys, and buzzer drive. The 16MHz core executes touch-free mechanical key scanning and safety interlock logic with wide margin, while 64KB Flash stores multi-language strings and fault history in EEPROM. Single-cycle instruction execution keeps interrupt latency predictable for safety-critical timing. Firmware field updates via ISP reduce service costs. Designers should isolate mains-sensing circuits optically and keep LCD bias networks close to the MCU per layout guidance.
推荐
POS and Access Control Terminals
Point-of-sale terminals and access-control readers use the ATMEGA649-16MU where a segment LCD, keypad matrix, and serial links converge: 54/69 GPIO accommodate the matrix and indicators while SPI and USART connect to card interfaces or RS-485 backbones. The 2KB EEPROM stores keys, IDs, and configuration through power loss, and 64KB Flash supports multi-protocol firmware. JTAG enables secure production programming and boundary-scan test before enclosure sealing, reducing field failures. The exposed-pad QFN provides the solid ground reference that noisy switching supplies in these products require. Keep crystal and LCD traces short, and follow datasheet decoupling guidance on all supply pins.
推荐
推荐产品汇总
工程参考数据： ATMEGA649-16MU ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | ATMEGA649A-MU | ATMEGA649V-8MUR | ATMEGA649-16MI | ATMEGA645-16MU |
|---|---|---|---|---|---|
| Package | 64-QFN (9x9) exposed pad | 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 |
| Flash | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB |
| EEPROM / SRAM | 2 KB / 4 KB | 2 KB / 4 KB | 2 KB / 4 KB | 2 KB / 4 KB | 2 KB / 4 KB |
| Max Speed | 16 MHz | 16 MHz | 8 MHz | 16 MHz | 16 MHz |
| LCD Controller | Yes (on-chip, internal contrast control) | Yes | Yes | Yes | Yes |
| JTAG Debug / Boundary-Scan | Yes | Yes | Yes | Yes | Yes |
| Generation / Grade | Standard (ATmega649 base) | Newer A-generation (recommended for new designs) | V low-voltage grade | Industrial temperature grade | ATmega645 peripheral variant |
关键差异点
- On-chip LCD controller with internal contrast control （对比 ATMEGA644-20AU)
- Newer-generation silicon available pin-to-pin （对比 ATMEGA649A-MU)
- Full-speed 16MHz operation （对比 ATMEGA649V-8MUR)
设计说明
The 64-QFN exposed pad must be soldered to a grounded thermal pad on the PCB; this pad is the primary ground return for the AVR core and the LCD driver, not merely a thermal feature. Use a 3x3 to 5x5 via array under the pad connected to the ground plane, per standard Microchip QFN layout guidance. Insufficient exposed-pad soldering is the most common cause of intermittent resets and LCD ghost segments on MLF-package ATmega parts.
Decouple every VCC/AVCC pin pair with 100nF ceramic capacitors placed within 2mm of the pins, plus one bulk 10uF per supply rail. AVCC must be connected even if the ADC family peripherals are unused; a floating AVCC causes LCD contrast instability. If a switching pre-regulator feeds the MCU rail, add an LC filter or LDO stage because the LCD controller's contrast depends on a quiet supply.
The JTAG interface shares pins with PORTC GPIO and is enabled by default on ATmega parts with JTAG; if PORTC is needed for general I/O, disable JTAG via the JTD bit or fuse at startup, otherwise four I/O lines remain unavailable. Also note that the manufacturer designates ATMEGA649A as the newer device - for new designs start with the A-variant and qualify firmware on both if you must source the original part in parallel.
合规信息
Distributor data references a GREEN package variant for the -16MI sibling, suggesting lead-free/RoHS-compliant packaging for the family, but explicit compliance status for ATMEGA649-16MU was not stated in the provided data. Verify on the Microchip product page.
