ATMEGA64L-8AJ - 8MHz 64KB Flash AVR MCU | Microchip
料号： ATMEGA64L-8AJ ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $7.42 | $7.42 |
| 10 | $6.68 | $66.80 |
| 100 | $5.92 | $592.00 |
| 500 | $5.31 | $2,655.00 |
| 1,000 | $4.75 | $4,750.00 |
ATMEGA64L-8AJ 概述
An AVR microcontroller is an 8-bit reduced-instruction-set (RISC) MCU built around a Harvard architecture that executes most instructions in a single clock cycle, placing it in the embedded microcontroller tier of the semiconductor hierarchy: microcontroller -> integrated circuit -> semiconductor. AVR MCUs from Microchip Technology are widely used in industrial control, consumer devices, and automotive sub-systems.
Key features include 64KB self-programmable Flash with a separate boot lock section, 53 general-purpose I/O lines, and rich peripherals: two 8-bit timers, two 16-bit timers, an 8-channel 10-bit ADC, two UART/USART ports, SPI, and I2C (TWI) interfaces. JTAG boundary scan and on-chip debug simplify development and production testing.
The AVR core achieves close to 1 MIPS per MHz throughput, so the 8MHz ATmega64L delivers roughly 8 MIPS while consuming low quiescent power, with six software-selectable sleep modes for battery-operated designs. The external memory interface expands addressable SRAM beyond the internal 4KB, and a full-duplex UART plus master/slave SPI support multi-chip systems.
Typical applications include industrial automation controllers, HVAC and building management panels, data loggers, and 5V legacy board upgrades where the 100% pin-compatible replacement of ATmega103 is exploited.
Design consideration: keep the L-grade 8MHz frequency limit in mind - if your firmware needs more than 8MHz at 5V, select the ATMEGA64-16AU 16MHz variant on the same footprint.
This page synthesizes distributor availability, drop-in alternatives, pinout, and practical design notes not found in the manufacturer datasheet.
直接替换替代料： ATMEGA64L-8AJ ——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： ATMEGA64L-8AJ （相同外形与封装尺寸） ——差异在于 Package, ADC, EEPROM, Operating Temperature, Program Memory Size.
快速对比工具——选择替代料号进行并排对比：
ATMEGA64L-8AU
✅ 直接替换✓ 有现货
$4.55 / 个
查看数据手册 →ATMEGA64L-8AI
✅ 直接替换✓ 有现货
$6.7 / 个
查看数据手册 →ATMEGA64A-AUR
✅ 直接替换✓ 有现货
$4.1 / 个
查看数据手册 →ATMEGA64-16AU
✅ 直接替换✓ 有现货
$7.23 / 个
查看数据手册 →ATMEGA103-6AC
✅ 直接替换✓ 有现货
$8.2 / 个
查看数据手册 →ATMEGA64L-8AJ 最大额定值与电气特性
| Core Architecture | 8-bit AVR RISC |
| Program Memory (Flash) | 64KB (32K x 16) |
| SRAM | 4KB |
| EEPROM | 2KB |
| Maximum Clock Speed | 8MHz |
| 电源电压 | 2.7V to 5.5V |
| 数据总线宽度 | 8 bit |
| I/O Ports | 53 I/O lines |
| ADC | 8-channel 10-bit |
| Communication Interfaces | I2C (TWI), SPI, 2x UART/USART |
| Timers | 2x 8-bit, 2x 16-bit |
| 封装 | 64-TQFP (14x14 mm) |
| 安装类型 | Surface Mount |
| On-Chip Debug | JTAG (IEEE 1149.1) |
| External Memory Interface | Yes (expandable SRAM) |
| Lifecycle Stage | ACTIVE |
| Approximate Throughput | Up to 8 MIPS at 8MHz |
ATMEGA64L-8AJ 引脚配置
| 引脚 1 | PEN — Programming Enable (high-voltage parallel programming) |
| 引脚 2 | PB0/SS — Port B bit 0 / SPI Slave Select |
| 引脚 3 | PB1/SCK — Port B bit 1 / SPI Serial Clock |
| 引脚 4 | PB2/MOSI — Port B bit 2 / SPI Master Output |
| 引脚 5 | PB3/MISO — Port B bit 3 / SPI Master Input |
| 引脚 6 | PB4/OC0 — Port B bit 4 / Timer0 Output Compare |
| 引脚 7 | PB5/OC1A — Port B bit 5 / Timer1 Output Compare A |
| 引脚 8 | PB6/OC1B — Port B bit 6 / Timer1 Output Compare B |
| 引脚 9 | PB7/OC2 — Port B bit 7 / Timer2 Output Compare |
| 引脚 10 | RESET — Active-low reset input |
| 引脚 11 | VCC — Digital supply voltage |
| 引脚 12 | GND — Ground |
| 引脚 13 | XTAL2 — Crystal oscillator output |
| 引脚 14 | XTAL1 — Crystal oscillator input / external clock |
| 引脚 15 | PD0/SCL/INT0 — Port D bit 0 / TWI SCL / External Interrupt 0 |
| 引脚 16 | PD1/SDA/INT1 — Port D bit 1 / TWI SDA / External Interrupt 1 |
| 引脚 17 | PD2/RXD1 — Port D bit 2 / USART1 receive |
| 引脚 18 | PD3/TXD1 — Port D bit 3 / USART1 transmit |
| 引脚 19 | PD4/IC1 — Port D bit 4 / Timer1 Input Capture |
| 引脚 20 | PD5/XCK1 — Port D bit 5 / USART1 external clock |
| 引脚 21 | PD6/T1 — Port D bit 6 / Timer1 external counter |
| 引脚 22 | PD7/T2 — Port D bit 7 / Timer2 external counter |
| 引脚 23 | PE0/RXD0 — Port E bit 0 / USART0 receive |
| 引脚 24 | PE1/TXD0 — Port E bit 1 / USART0 transmit |
| 引脚 25 | PE2/AIN0 — Port E bit 2 / Analog Comparator positive input |
| 引脚 26 | PE3/AIN1 — Port E bit 3 / Analog Comparator negative input |
| 引脚 27 | PE4/OC3B/INT4 — Port E bit 4 / Timer3 Output Compare B / INT4 |
| 引脚 28 | PE5/OC3C/INT5 — Port E bit 5 / Timer3 Output Compare C / INT5 |
| 引脚 29 | PE6/T3/INT6 — Port E bit 6 / Timer3 clock / INT6 |
| 引脚 30 | PE7/ICP3/INT7 — Port E bit 7 / Timer3 Input Capture / INT7 |
| 引脚 31 | VCC — Digital supply voltage |
| 引脚 32 | GND — Ground |
| 引脚 33 | PF0/ADC0 — Port F bit 0 / ADC channel 0 |
| 引脚 34 | PF1/ADC1 — Port F bit 1 / ADC channel 1 |
| 引脚 35 | PF2/ADC2 — Port F bit 2 / ADC channel 2 |
| 引脚 36 | PF3/ADC3 — Port F bit 3 / ADC channel 3 |
| 引脚 37 | PF4/ADC4/TCK — Port F bit 4 / ADC channel 4 / JTAG TCK |
| 引脚 38 | PF5/ADC5/TMS — Port F bit 5 / ADC channel 5 / JTAG TMS |
| 引脚 39 | PF6/ADC6/TDO — Port F bit 6 / ADC channel 6 / JTAG TDO |
| 引脚 40 | PF7/ADC7/TDI — Port F bit 7 / ADC channel 7 / JTAG TDI |
| 引脚 41 | PG0/WR — Port G bit 0 / External memory write strobe |
| 引脚 42 | PG1/RD — Port G bit 1 / External memory read strobe |
| 引脚 43 | PC0/A8 — Port C bit 0 / External memory address bit 8 |
| 引脚 44 | PC1/A9 — Port C bit 1 / External memory address bit 9 |
| 引脚 45 | PC2/A10 — Port C bit 2 / External memory address bit 10 |
| 引脚 46 | PC3/A11 — Port C bit 3 / External memory address bit 11 |
| 引脚 47 | PC4/A12 — Port C bit 4 / External memory address bit 12 |
| 引脚 48 | PC5/A13 — Port C bit 5 / External memory address bit 13 |
| 引脚 49 | PC6/A14 — Port C bit 6 / External memory address bit 14 |
| 引脚 50 | PC7/A15 — Port C bit 7 / External memory address bit 15 |
| 引脚 51 | GND — Ground |
| 引脚 52 | VCC — Digital supply voltage |
| 引脚 53 | PA0/AD0 — Port A bit 0 / External memory address/data bit 0 |
| 引脚 54 | PA1/AD1 — Port A bit 1 / External memory address/data bit 1 |
| 引脚 55 | PA2/AD2 — Port A bit 2 / External memory address/data bit 2 |
| 引脚 56 | PA3/AD3 — Port A bit 3 / External memory address/data bit 3 |
| 引脚 57 | PA4/AD4 — Port A bit 4 / External memory address/data bit 4 |
| 引脚 58 | PA5/AD5 — Port A bit 5 / External memory address/data bit 5 |
| 引脚 59 | PA6/AD6 — Port A bit 6 / External memory address/data bit 6 |
| 引脚 60 | PA7/AD7 — Port A bit 7 / External memory address/data bit 7 |
| 引脚 61 | AREF — ADC analog reference input |
| 引脚 62 | AVCC — Analog supply for ADC and Port F |
| 引脚 63 | AGND — Analog ground |
| 引脚 64 | PG2/ALE — Port G bit 2 / External memory address latch enable |
典型应用
ATMEGA64L-8AJ 适用于 6 应用s: Industrial Automation Controllers, HVAC and Building Management Panels, Battery-Powered Data Loggers, Legacy ATmega103 Board Maintenance, Multi-Protocol Communication Nodes, 5V Legacy Board Upgrades and Retrofits.
Industrial Automation Controllers
The ATMEGA64L-8AJ fits industrial automation controllers because its 64KB Flash stores complex state machines and communication stacks, while 53 I/O lines drive relays, indicators, and keypads directly. The dual full-duplex UART/USART ports enable simultaneous Modbus RTU slave and diagnostic links, and the I2C/SPI interfaces connect RTCs and EEPROM for configuration storage. Operating from 2.7V to 5.5V, the part integrates cleanly on legacy 5V control boards. JTAG boundary-scan supports production test on densely populated boards, and the external memory interface expands beyond 4KB SRAM when data buffering grows, all at roughly 8 MIPS throughput.
推荐
HVAC and Building Management Panels
Building management and HVAC control panels benefit from the ATMEGA64L-8AJ's 8-channel 10-bit ADC, which digitizes up to eight temperature, humidity, or pressure sensor inputs without an external converter. The 2KB EEPROM preserves setpoints and schedules across power cycles, and the TWI (I2C) interface chains multiple peripheral devices on a two-wire bus. The 8MHz L-grade device runs cool and supports sleep modes between polling cycles, reducing average power in always-on installations. UART connectivity reports status to a supervisor network, while the 64KB Flash holds menus, fonts, and schedule tables for local operator interfaces on 5V panels.
推荐
Battery-Powered Data Loggers
For battery-powered data loggers, the ATMEGA64L-8AJ combines six software-selectable sleep modes with 2.7V operation, extending battery life in field instruments that sample for months. The 8-channel 10-bit ADC captures multi-sensor analog inputs, and the external memory interface addresses external SRAM beyond the internal 4KB for long recording sessions. SPI handles fast serial flash or SD-card style storage, while one UART streams logged data to a PC during retrieval. The 64KB Flash reserves boot-section space for firmware updates in the field via the self-programming bootloader, eliminating recalls when calibration or logging logic changes are required after deployment.
推荐
Legacy ATmega103 Board Maintenance
The ATmega64 is, per Microchip's datasheet, 100% pin compatible with ATmega103 and can replace it on current printed circuit boards, making ATMEGA64L-8AJ the standard migration device for maintaining legacy ATmega103-based equipment. As ATmega103 becomes scarce, production lines solder ATmega64 into the existing TQFP-64 footprint with no PCB change. The migration application notes document the register-level differences that firmware must absorb, typically small peripheral initialization changes. Hardware compatibility preserves tooling, fixtures, and validation investment. The 2.7V to 5.5V L-grade supply range covers both the original 5V boards and any 3.3V derivatives in the same product family.
推荐
Multi-Protocol Communication Nodes
Communication nodes benefit from the ATMEGA64L-8AJ's two independent UART/USART ports, which allow simultaneous operation of, for example, a Modbus or proprietary field bus on one port and a service console on the other. SPI and TWI add local expansion to port expanders, ADCs, and displays, so a single MCU can bridge field wiring and a local touch interface. The external bus interface (ALE/RD/WR with multiplexed address-data ports) offloads memory-hungry protocol buffers to external SRAM. At 8MHz the AVR core delivers roughly 8 MIPS, sufficient for interrupt-driven framing, checksum computation, and packet routing at field-bus data rates while leaving headroom in the 64KB Flash.
推荐
5V Legacy Board Upgrades and Retrofits
Many industrial products in the field remain 5V designs, and the ATMEGA64L-8AJ is a natural fit for these retrofits because the L grade tolerates 5V while also accepting 3.3V, giving one BOM part across board revisions. The 64-TQFP (14x14 mm) footprint is mechanically robust for wave and selective soldering processes common in repair shops. The 2KB EEPROM emulates old NV-RAM setpoint storage, and the 10-bit ADC replaces external A/D chips on older boards. JTAG on-chip debug shortens bring-up of upgraded firmware, and the boot-lock Flash section enables authenticated firmware updates through an existing serial port without socketing devices on serviced boards.
推荐
推荐产品汇总
工程参考数据： ATMEGA64L-8AJ ——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 | ATMEGA64L-8AU | ATMEGA64L-8AI | ATMEGA64A-AUR | ATMEGA64-16AU |
|---|---|---|---|---|---|
| Package | 64-TQFP (14x14) | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64KB (32K x 16) | 64KB | 64KB | 64KB | 64KB |
| SRAM | 4KB | 4KB | 4KB | 4KB | 4KB |
| Maximum Clock Speed | 8MHz | 8MHz | 8MHz | 16MHz (A-generation spec) | 16MHz |
| Supply Voltage | 2.7V to 5.5V | 2.7V to 5.5V | 2.7V to 5.5V | 2.7V to 5.5V | 4.5V to 5.5V |
关键差异点
- Widest supply range in same footprint （对比 ATMEGA64-16AU)
- 100% pin-compatible ATmega103 replacement （对比 ATmega103)
- Dual UART/USART on a mid-range 8-bit AVR （对比 ATMEGA32L-8AI)
设计说明
Decouple all three VCC pins (11, 31, 52) with 100nF ceramic capacitors placed as close as possible to each pin, plus one bulk 10uF capacitor per supply rail. AVCC (pin 62) must be connected to VCC through a low-pass filter (e.g., 10uH inductor or ferrite bead plus 100nF) when ADC accuracy matters, per the ATmega64/L datasheet power-supply guidance. At 2.7V minimum operation, verify brown-out detector settings, since the BOD threshold must sit between the operating voltage floor and the minimum VCC to protect EEPROM writes.
Keep AGND (pin 63) and AREF (pin 61) routing away from the switching nodes of any upstream regulator; connect AGND to a quiet analog ground island tied to digital ground at a single point. Star-route the crystal (XTAL1/XTAL2, pins 14/13) with short traces and place load capacitors within 3-5mm of the pins to minimize jitter and startup failures. If the external memory bus (PA0-PA7, PC0-PC7, ALE, RD, WR) is used, keep the AD bus length-matched and add series 22-33 ohm resistors on ALE/WR/RD to control ringing on 5V-level strobes.
The most frequent integration error is clocking this L-grade part above 8MHz - unlike some AVR speed grades, ATMEGA64L-8AJ is not rated higher even at 5V; use ATMEGA64-16AU for faster clocks. Second, JTAG enable is fused on by default and JTAG pins PF4-PF7 double as ADC4-ADC7; if you need all eight ADC channels, disable JTAGEN via fuse or software JTD bit. Third, when migrating from ATmega103, remember register and bit positions differ - follow the Microchip migration application notes rather than reusing register definitions.
合规信息
Compliance attributes were not stated in the provided verified web data; verify RoHS/REACH status on the Microchip product page or distributor listing before procurement.
