ATMEGA64L-8MU - 8-bit AVR MCU, 8MHz, 64KB Flash | Microchip
MPN： ATMEGA64L-8MU ✗ 停產ATMEGA64L-8MU 概覽
An 8-bit microcontroller is a complete computer system on a single integrated circuit, combining a processor core, memory, and peripherals such as timers, UARTs, ADCs, and SPI/I2C interfaces. The ATmega64 belongs to the AVR family of enhanced RISC microcontrollers, positioned within the broader hierarchy of embedded processors and power-management-capable MCU platforms. AVR cores execute most instructions in a single clock cycle, achieving throughputs approaching one MIPS per MHz.
Key features include 130 powerful instructions with mostly single-cycle execution, 32 x 8 general purpose working registers, fully static operation, and 53 general purpose I/O lines. The 64KB self-programmable Flash supports in-system programming via SPI, and the 4KB internal SRAM plus 2KB EEPROM provide ample on-chip data storage for embedded control tasks.
Technically, the ATMEGA64L-8MU is based on the AVR enhanced RISC architecture with a Harvard bus design that fetches instructions and data simultaneously. The L-suffix grade supports lower supply voltage operation than the standard grade, making it suitable for battery-powered and 3V-class designs, while the U-suffix temperature range covers -40C to +85C for industrial environments. The low-power CMOS process allows the system designer to optimize power consumption versus processing speed.
Typical applications include industrial automation and control panels, building and HVAC controllers, embedded instrumentation, and legacy system maintenance where the ATmega64 replaces the earlier ATmega103 on existing PCBs, as it is 100% pin compatible with that device.
When designing with this part, note that Microchip lists the ATmega64 as a mature product not recommended for new designs, with the ATmega64A as the recommended replacement; pin-compatible migration within the ATmega64/ATmega128 family is documented in Microchip application notes.
This page synthesizes distributor pricing, drop-in alternatives, pin-compatibility guidance, and practical design notes not found in the manufacturer datasheet, providing information gain beyond raw specification listings.
直接替換替代品，適用於 ATMEGA64L-8MU — 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： ATMEGA64L-8MU （相同外形與佔位） — 差異在於 Package, Operating Temperature, Supply Voltage Range, Debug Interface, Instruction Set.
ATMEGA64L-8MJ
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA64A-MUR
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA649A-MU
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA128A-MUR
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA2561-16MU
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA64L-8MU 最大額定值與電氣特性
| Core Architecture | AVR 8-bit RISC |
| Max Clock Frequency | 8 MHz |
| Program Memory Size | 64 KB (32K x 16) Flash |
| Program Memory Type | In-System Programmable Flash |
| SRAM Size | 4 KB |
| EEPROM Size | 2 KB |
| Number of I/O | 53 |
| Instruction Set | 130 instructions, most single-clock cycle |
| General Purpose Registers | 32 x 8 |
| 封裝 | 64-QFN (9x9 mm) |
| 安裝類型 | Surface Mount |
| 工作溫度 | -40C to +85C |
| 資料匯流排寬度 | 8 bit |
| Pin Compatibility | 100% pin compatible with ATmega103 |
| 生命週期狀態 | Mature product; not recommended for new designs; replaced by ATmega64A |
ATMEGA64L-8MU 64-qfn (9x9 mm) 腳位配置指南
ATMEGA64L-8MU（64-qfn (9x9 mm) 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： ATMEGA64L-8MU.
請參閱 資料表 以查看完整腳位配置。
典型應用
ATMEGA64L-8MU 適用於 6 應用s: Industrial Automation and Control, Building and HVAC Controllers, Embedded Instrumentation, Legacy System Maintenance and ATmega103 Replacement, Motor and Power Control Subsystems, IoT Sensor Nodes and Gateways.
Industrial Automation and Control
The ATMEGA64L-8MU fits industrial control nodes that need multiple concurrent communication channels and abundant I/O: its 53 GPIO lines, two USARTs, SPI, and TWI (I2C) interfaces allow a single MCU to drive relays, read sensors, and link to a PLC backplane simultaneously. The 64KB Flash supports substantial control logic and bootloader-based field updates, while the 2KB EEPROM stores calibration and configuration data through power cycles. Operating from -40C to +85C, the U-suffix grade meets industrial cabinet temperature requirements. The 8MHz clock keeps EMI low compared to faster 16MHz grades, simplifying compliance in factory environments. Designers typically run a watchdog timer and use JTAG for on-chip debugging during commissioning, reducing development iterations on the production floor.
推薦
Building and HVAC Controllers
Thermostats, zone controllers, and ventilation units benefit from the ATMEGA64L-8MU's combination of a 10-bit ADC for temperature and humidity sensing, 10-bit PWM-capable timers for fan and valve actuation, and 53 I/O lines for keypads and display backplanes. The L-grade low-voltage envelope supports designs powered from 3V-class rails, and the AVR core's near-1 MIPS-per-MHz throughput lets the controller sleep between measurement cycles, extending battery life in wireless zone sensors. The 2KB EEPROM retains setpoints and schedules without external non-volatile memory. With 64KB Flash there is room for communication stacks such as Modbus RTU over USART, enabling integration into building management systems without an external communication coprocessor.
推薦
Embedded Instrumentation
Bench and portable instruments use the ATMEGA64L-8MU as a front-panel and measurement controller. Its 8-channel 10-bit ADC digitizes auxiliary analog inputs, while the 16-bit timers capture frequency and pulse-width measurements with input-capture hardware for deterministic timing. The JTAG interface supports on-chip debugging and boundary scan, which accelerates bring-up and production test of the instrument PCB. The 64KB Flash accommodates menu frameworks, calibration tables in EEPROM, and serial protocols for PC connectivity over USART or USB-bridge chips. The fully static core allows clocking down for low-power standby in battery-operated field instruments, and the 9x9 mm QFN package keeps the controller footprint compact on dense analog boards.
推薦
Legacy System Maintenance and ATmega103 Replacement
A primary use case for the ATMEGA64L-8MU is sustaining older products built around the ATmega103. According to the Microchip datasheet, the ATmega64 is 100% pin compatible with the ATmega103 and can replace it on current printed circuit boards, allowing manufacturers to keep legacy boards in production without layout changes. The migration application note documents fuse and register differences to address in firmware. Similarly, designs originally qualified with the ATmega64 family can be maintained with the ATMEGA64A as the die-level successor while retaining the same footprint. This makes the part valuable for spare-part inventories, medical and industrial equipment service lines, and long-lifecycle products where requalification of a new PCB is costly.
推薦
Motor and Power Control Subsystems
The ATMEGA64L-8MU suits low-end motor control and power-management boards: four timers with PWM outputs drive DC motor H-bridges and LED or heater loads, the analog comparator plus 10-bit ADC supports current-limit detection loops, and the 8MHz clock keeps switching-control jitter low for slow-speed motor tasks. The -40C to +85C operating range covers drive enclosures mounted in unconditioned environments. With two USARTs, one channel can connect to a supervisor while the second services a local HMI, all within one 64-pin QFN. The self-programmable Flash enables field firmware updates for evolving control profiles. Designers should budget SRAM carefully, since the 4KB on-chip memory bounds the complexity of advanced sensor-fusion control algorithms.
推薦
IoT Sensor Nodes and Gateways
For wired IoT nodes, the ATMEGA64L-8MU provides a low-cost host that manages sensor acquisition and network-module communication. Two USARTs connect simultaneously to a radio or Ethernet module and a diagnostic console; SPI interfaces external flash or ADCs; and TWI (I2C) reads digital sensors. The L-grade low-voltage operation matches 3.3V rail systems common in IoT hardware, and the fully static core supports aggressive sleep scheduling for battery-powered deployments. The 64KB Flash holds protocol stacks and local buffering logic, while EEPROM stores device identity and network credentials through reflows and power loss. The 9x9 mm QFN footprint integrates cleanly into compact sensor-node PCBs alongside the radio module and power section.
推薦
推薦產品摘要
工程參考資料，適用於 ATMEGA64L-8MU — 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 | ATMEGA64L-8MJ | ATMEGA64A-MUR | ATMEGA649A-MU | ATMEGA128A-MU |
|---|---|---|---|---|---|
| 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 |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 8 MHz | 8 MHz | 16 MHz | 16 MHz | 16 MHz |
| Program Flash | 64 KB | 64 KB | 64 KB | 64 KB | 128 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 8 KB |
| EEPROM | 2 KB | 2 KB | 2 KB | 2 KB | 4 KB |
| Special Features | ATmega103 pin-compatible legacy replacement | Identical to this product | Active recommended successor die | Integrated segment LCD controller | Double program memory for larger firmware |
| Lifecycle Status | Mature / NRND, replaced by ATmega64A | Mature / NRND | Active (recommended) | Active | Active |
主要差異化特點
- Identical L-grade option for BOM continuity (對比ATMEGA64A-MUR)
- Legacy ATmega103 replacement path (對比ATMEGA649A-MU)
- Lowest cost within footprint for modest firmware (對比ATMEGA128A-MU)
設計說明
The 64-QFN (9x9 mm) MLF package has a large exposed die paddle on the underside that must be soldered to a grounded copper pour for mechanical reliability and thermal/electrical performance. Follow the Atmel-2490 datasheet land-pattern recommendation, and use an array of thermal vias (typically 5x5 or similar) connecting the paddle to internal ground planes. Because MLF leads are on the package perimeter bottom edge, inspect solder joints with X-ray or use a stencil with reduced paste coverage on the paddle to avoid excessive solder wicking that can lift perimeter pins during reflow.
When migrating firmware or production from ATMEGA64L-8MU to the ATMEGA64A, do not assume identical fuse defaults. The ATmega64A successor die can differ in fuse bit defaults, BOD calibration, and analog peripheral calibration bytes. Microchip's migration documentation for the ATmega64 family should be reviewed and the configuration section of your programming files updated before first production build. Also confirm JTAG enable fuse state: with JTAG enabled, four of the port C pins are unavailable as GPIO, a common cause of I/O shortages in ATmega64 designs.
The L suffix designates the low-voltage/8MHz speed grade; do not overclock beyond 8MHz if the supply sits at the low end of the L-grade range, as the AVR frequency-versus-voltage curve in the datasheet defines a safe operating region. Decouple VCC and AVCC separately with 100nF ceramics placed within a few millimeters of each pin pair, and tie AVCC to VCC through a low-pass filter (for example a 10 ohm resistor or ferrite plus 100nF/10uF) if the 10-bit ADC is used in noisy motor or switching environments. Use the internal BOD fuse to prevent EEPROM corruption during brownouts.
Keep the JTAG (port C) traces short and, if boundary scan is used in production test, reserve header access on the PCB since the four JTAG pins double as GPIO only when the JTAGEN fuse is disabled. For the two USARTs, route TX/RX away from the crystal lines; if an external crystal is used for the 8MHz clock, load capacitors should follow the crystal manufacturer recommendation and the traces kept under 10-15 mm to avoid startup margin issues. Series termination (22-33 ohm) on long UART lines reduces ringing at cable interfaces.
合規資訊
RoHS/lead-free status per Microchip standard offering for MLF/QFN packages; obtain formal compliance certificates from the Microchip product page or distributor. REACH and halogen-free declarations not found in provided data.
