ATMEGA64L-8AJ - 8MHz 64KB Flash AVR MCU | Microchip
MPN: ATMEGA64L-8AJ ✓ نشطATMEGA64L-8AJ نظرة عامة
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.
بدائل مباشرة لـ ATMEGA64L-8AJ — نفس الحزمة، متوافق دبوس بدبوس. تُستثنى القطع ذات الحزم المختلفة التي تتطلب تعديل PCB.
الطرازات في هذه السلسلة
طرازات من نفس السلسلة متوافقة تمامًا مع ATMEGA64L-8AJ (نفس عامل الشكل والبصمة) — يختلف في Package, ADC, EEPROM, Operating Temperature, Program Memory Size.
ATMEGA64L-8AU
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←ATMEGA64L-8AI
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←ATMEGA64A-AUR
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←ATMEGA64-16AU
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←ATMEGA103-6AC
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←ATMEGA64L-8AJ الحدود القصوى والخصائص الكهربائية
| Core Architecture | 8-bit AVR RISC |
| Program Memory (Flash) | 64KB (32K x 16) |
| SRAM | 4KB |
| EEPROM | 2KB |
| Maximum Clock Speed | 8MHz |
| جهد التغذية | 2.7V to 5.5V |
| عرض ناقل البيانات | 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 |
| العلبة | 64-TQFP (14x14 mm) |
| نوع التركيب | 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 |
تكوين أطراف ATMEGA64L-8AJ
| دبوس 1 | PEN — Programming Enable (high-voltage parallel programming) |
| دبوس 2 | PB0/SS — Port B bit 0 / SPI Slave Select |
| دبوس 3 | PB1/SCK — Port B bit 1 / SPI Serial Clock |
| دبوس 4 | PB2/MOSI — Port B bit 2 / SPI Master Output |
| دبوس 5 | PB3/MISO — Port B bit 3 / SPI Master Input |
| دبوس 6 | PB4/OC0 — Port B bit 4 / Timer0 Output Compare |
| دبوس 7 | PB5/OC1A — Port B bit 5 / Timer1 Output Compare A |
| دبوس 8 | PB6/OC1B — Port B bit 6 / Timer1 Output Compare B |
| دبوس 9 | PB7/OC2 — Port B bit 7 / Timer2 Output Compare |
| دبوس 10 | RESET — Active-low reset input |
| دبوس 11 | VCC — Digital supply voltage |
| دبوس 12 | GND — Ground |
| دبوس 13 | XTAL2 — Crystal oscillator output |
| دبوس 14 | XTAL1 — Crystal oscillator input / external clock |
| دبوس 15 | PD0/SCL/INT0 — Port D bit 0 / TWI SCL / External Interrupt 0 |
| دبوس 16 | PD1/SDA/INT1 — Port D bit 1 / TWI SDA / External Interrupt 1 |
| دبوس 17 | PD2/RXD1 — Port D bit 2 / USART1 receive |
| دبوس 18 | PD3/TXD1 — Port D bit 3 / USART1 transmit |
| دبوس 19 | PD4/IC1 — Port D bit 4 / Timer1 Input Capture |
| دبوس 20 | PD5/XCK1 — Port D bit 5 / USART1 external clock |
| دبوس 21 | PD6/T1 — Port D bit 6 / Timer1 external counter |
| دبوس 22 | PD7/T2 — Port D bit 7 / Timer2 external counter |
| دبوس 23 | PE0/RXD0 — Port E bit 0 / USART0 receive |
| دبوس 24 | PE1/TXD0 — Port E bit 1 / USART0 transmit |
| دبوس 25 | PE2/AIN0 — Port E bit 2 / Analog Comparator positive input |
| دبوس 26 | PE3/AIN1 — Port E bit 3 / Analog Comparator negative input |
| دبوس 27 | PE4/OC3B/INT4 — Port E bit 4 / Timer3 Output Compare B / INT4 |
| دبوس 28 | PE5/OC3C/INT5 — Port E bit 5 / Timer3 Output Compare C / INT5 |
| دبوس 29 | PE6/T3/INT6 — Port E bit 6 / Timer3 clock / INT6 |
| دبوس 30 | PE7/ICP3/INT7 — Port E bit 7 / Timer3 Input Capture / INT7 |
| دبوس 31 | VCC — Digital supply voltage |
| دبوس 32 | GND — Ground |
| دبوس 33 | PF0/ADC0 — Port F bit 0 / ADC channel 0 |
| دبوس 34 | PF1/ADC1 — Port F bit 1 / ADC channel 1 |
| دبوس 35 | PF2/ADC2 — Port F bit 2 / ADC channel 2 |
| دبوس 36 | PF3/ADC3 — Port F bit 3 / ADC channel 3 |
| دبوس 37 | PF4/ADC4/TCK — Port F bit 4 / ADC channel 4 / JTAG TCK |
| دبوس 38 | PF5/ADC5/TMS — Port F bit 5 / ADC channel 5 / JTAG TMS |
| دبوس 39 | PF6/ADC6/TDO — Port F bit 6 / ADC channel 6 / JTAG TDO |
| دبوس 40 | PF7/ADC7/TDI — Port F bit 7 / ADC channel 7 / JTAG TDI |
| دبوس 41 | PG0/WR — Port G bit 0 / External memory write strobe |
| دبوس 42 | PG1/RD — Port G bit 1 / External memory read strobe |
| دبوس 43 | PC0/A8 — Port C bit 0 / External memory address bit 8 |
| دبوس 44 | PC1/A9 — Port C bit 1 / External memory address bit 9 |
| دبوس 45 | PC2/A10 — Port C bit 2 / External memory address bit 10 |
| دبوس 46 | PC3/A11 — Port C bit 3 / External memory address bit 11 |
| دبوس 47 | PC4/A12 — Port C bit 4 / External memory address bit 12 |
| دبوس 48 | PC5/A13 — Port C bit 5 / External memory address bit 13 |
| دبوس 49 | PC6/A14 — Port C bit 6 / External memory address bit 14 |
| دبوس 50 | PC7/A15 — Port C bit 7 / External memory address bit 15 |
| دبوس 51 | GND — Ground |
| دبوس 52 | VCC — Digital supply voltage |
| دبوس 53 | PA0/AD0 — Port A bit 0 / External memory address/data bit 0 |
| دبوس 54 | PA1/AD1 — Port A bit 1 / External memory address/data bit 1 |
| دبوس 55 | PA2/AD2 — Port A bit 2 / External memory address/data bit 2 |
| دبوس 56 | PA3/AD3 — Port A bit 3 / External memory address/data bit 3 |
| دبوس 57 | PA4/AD4 — Port A bit 4 / External memory address/data bit 4 |
| دبوس 58 | PA5/AD5 — Port A bit 5 / External memory address/data bit 5 |
| دبوس 59 | PA6/AD6 — Port A bit 6 / External memory address/data bit 6 |
| دبوس 60 | PA7/AD7 — Port A bit 7 / External memory address/data bit 7 |
| دبوس 61 | AREF — ADC analog reference input |
| دبوس 62 | AVCC — Analog supply for ADC and Port F |
| دبوس 63 | AGND — Analog ground |
| دبوس 64 | PG2/ALE — Port G bit 2 / External memory address latch enable |
التطبيقات النموذجية
ATMEGA64L-8AJ مناسب لـ 6 التطبيقs: 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.
موصى به
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.
موصى به
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.
موصى به
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.
موصى به
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.
موصى به
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.
موصى به
ملخص المنتجات الموصى بها
بيانات مرجعية هندسية لـ ATMEGA64L-8AJ — المقارنة وإرشادات التصميم ومعلومات الامتثال.
دليل الاختيار
المقارنة مع البدائل
| المعامل | هذا المنتج | 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 |
أبرز الفروقات
- Widest supply range in same footprint (مقابلATMEGA64-16AU)
- 100% pin-compatible ATmega103 replacement (مقابلATmega103)
- Dual UART/USART on a mid-range 8-bit AVR (مقابلATMEGA32L-8AI)
ملاحظات التصميم
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.
معلومات الامتثال
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.
