ATMEGA64L-8AI - 8-bit AVR MCU 64KB Flash 8MHz | Microchip
MPN: ATMEGA64L-8AI ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $10.3 | $10.30 |
| 10 | $9.27 | $92.70 |
| 100 | $8.24 | $824.00 |
| 500 | $7.42 | $3,710.00 |
| 1,000 | $6.7 | $6,700.00 |
ATMEGA64L-8AI Overview
An AVR microcontroller is a Harvard-architecture 8-bit RISC device that executes most instructions in a single clock cycle from on-chip Flash memory. Within the product hierarchy, the ATmega64L sits under 8-bit AVR microcontrollers, which belong to the broader microcontroller (MCU) family, itself a subset of embedded processors and integrated circuits. The 'L' suffix denotes the low-voltage 2.7-5.5 V variant, while the '8' indicates the 8 MHz maximum clock, making it the low-power member of the ATmega64 family.
Key differentiators include 64 KB self-programming Flash with 10,000 write/erase cycles, 4 KB internal SRAM, 2 KB EEPROM with 100,000 write cycles, and a rich peripheral set: two USARTs, master/slave SPI, byte-oriented two-wire serial interface (I2C), and an 8-channel 10-bit successive-approximation ADC. The device also provides a programmable watchdog timer, brown-out detection, power-on reset, and six sleep modes for battery-powered designs.
The ATmega64L is architecturally identical to the ATmega64 but specified for 8 MHz at 2.7 V, whereas the standard ATmega64 runs to 16 MHz at 4.5 V. The ATmega64 is 100% pin compatible with the legacy ATmega103, allowing direct replacement on existing printed circuit boards, and Microchip application notes cover migration between ATmega64 and ATmega128.
Typical applications include industrial control and factory automation nodes, portable battery-powered instruments, medical monitoring devices, building automation and smart-home controllers, motor control front-ends, and legacy ATmega103 board upgrades. The 53 I/O lines and dual USARTs suit multi-sensor gateways, while the 2.7 V minimum supply supports 3.3 V and 5 V mixed logic systems.
A key design consideration is that the 8 MHz rating applies only down to 2.7 V; at 4.5-5.5 V the same silicon can be clocked faster, so verify the frequency/voltage curve before overclocking. Decouple every VCC pin with 100 nF ceramic capacitors and provide a clean analog supply for AVCC to preserve ADC accuracy.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, giving engineers a single reference for procurement and layout decisions.
Drop-in alternatives for ATMEGA64L-8AI — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ATMEGA64L-8AI (same form factor and footprint) — differing in Package, ADC, EEPROM, Operating Voltage, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA64L-8AU
✅ Drop-In✓ In Stock
$4.55 / Unit
View Datasheet →ATMEGA64-16AU
✅ Drop-In✓ In Stock
$7.23 / Unit
View Datasheet →ATMEGA64A-AUR
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →ATMEGA64A-AUR
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →ATMEGA64L-8AUR
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA64-16AUR
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA64L-8AI Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Program Memory | 64 KB self-programming Flash |
| Flash Endurance | 10,000 write/erase cycles |
| SRAM | 4 KB |
| EEPROM | 2 KB (100,000 write cycles) |
| Maximum Clock Frequency | 8 MHz |
| Throughput | Up to 8 MIPS at 8 MHz |
| Operating Voltage | 2.7 V to 5.5 V |
| Operating Temperature | -40C to +85C |
| Package | 64-TQFP (14x14 mm) |
| Mounting Type | Surface Mount |
| I/O Lines | 53 |
| ADC | 8-channel 10-bit successive approximation |
| Interfaces | 2x USART, SPI, I2C (TWI) |
| Debug Interface | JTAG (IEEE 1149.1) |
| Timers | 2x 8-bit, 2x 16-bit |
| PWM Channels | 8 |
| Instruction Set | 130 powerful instructions, most single-clock |
| General Purpose Registers | 32 x 8-bit |
| RoHS Status | Compliant |
ATMEGA64L-8AI Pin Configuration
| Pin 1 | PE6/RXD0/INT6 — Port E bit 6 / USART0 receive / external interrupt 6 |
| Pin 2 | PE7/TXD0/INT7 — Port E bit 7 / USART0 transmit / external interrupt 7 |
| Pin 3 | PB0/SS/SCK — Port B bit 0 / SPI slave select / SPI clock |
| Pin 4 | PB1/SCK — Port B bit 1 / SPI clock |
| Pin 5 | PB2/MOSI — Port B bit 2 / SPI master-out slave-in |
| Pin 6 | PB3/MISO — Port B bit 3 / SPI master-in slave-out |
| Pin 7 | PB4/OC0 — Port B bit 4 / timer 0 output compare |
| Pin 8 | PB5/OC1A — Port B bit 5 / timer 1 output compare A |
| Pin 9 | PB6/OC1B — Port B bit 6 / timer 1 output compare B |
| Pin 10 | PB7/OC2/OC1C — Port B bit 7 / timer 2 and timer 1 output compare |
| Pin 11 | TOSC2/PB7 — Timer oscillator pin 2 (crystal) |
| Pin 12 | TOSC1/PB6 — Timer oscillator pin 1 (crystal) |
| Pin 13 | XTAL2 — Inverting oscillator amplifier output |
| Pin 14 | XTAL1 — Inverting oscillator amplifier input |
| Pin 15 | RESET — Reset input (active low) |
| Pin 16 | VCC — Digital supply voltage |
| Pin 17 | GND — Ground |
| Pin 18 | PD0/SCL/INT0 — Port D bit 0 / I2C clock / external interrupt 0 |
| Pin 19 | PD1/SDA/INT1 — Port D bit 1 / I2C data / external interrupt 1 |
| Pin 20 | PD2/RXD1/INT2 — Port D bit 2 / USART1 receive / external interrupt 2 |
| Pin 21 | PD3/TXD1/INT3 — Port D bit 3 / USART1 transmit / external interrupt 3 |
| Pin 22 | PD4/IC1 — Port D bit 4 / timer 1 input capture |
| Pin 23 | PD5/XCK1 — Port D bit 5 / USART1 external clock |
| Pin 24 | PD6/T1 — Port D bit 6 / timer 1 counter input |
| Pin 25 | PD7/T2 — Port D bit 7 / timer 2 counter input |
| Pin 26 | PC0/A8 — Port C bit 0 / external memory address 8 |
| Pin 27 | PC1/A9 — Port C bit 1 / external memory address 9 |
| Pin 28 | PC2/A10 — Port C bit 2 / external memory address 10 |
| Pin 29 | PC3/A11 — Port C bit 3 / external memory address 11 |
| Pin 30 | PC4/A12 — Port C bit 4 / external memory address 12 |
| Pin 31 | PC5/A13 — Port C bit 5 / external memory address 13 |
| Pin 32 | PC6/A14 — Port C bit 6 / external memory address 14 |
| Pin 33 | PC7/A15 — Port C bit 7 / external memory address 15 |
| Pin 34 | VCC — Digital supply voltage |
| Pin 35 | GND — Ground |
| Pin 36 | PA7/AD7 — Port A bit 7 / external memory data 7 |
| Pin 37 | PA6/AD6 — Port A bit 6 / external memory data 6 |
| Pin 38 | PA5/AD5 — Port A bit 5 / external memory data 5 |
| Pin 39 | PA4/AD4 — Port A bit 4 / external memory data 4 |
| Pin 40 | PA3/AD3 — Port A bit 3 / external memory data 3 |
| Pin 41 | PA2/AD2 — Port A bit 2 / external memory data 2 |
| Pin 42 | PA1/AD1 — Port A bit 1 / external memory data 1 |
| Pin 43 | PA0/AD0 — Port A bit 0 / external memory data 0 |
| Pin 44 | VCC — Digital supply voltage |
| Pin 45 | GND — Ground |
| Pin 46 | AREF — Analog reference voltage for ADC |
| Pin 47 | AVCC — Analog supply voltage for ADC |
| Pin 48 | PF7/ADC7/TDI — Port F bit 7 / ADC channel 7 / JTAG test data in |
| Pin 49 | PF6/ADC6/TDO — Port F bit 6 / ADC channel 6 / JTAG test data out |
| Pin 50 | PF5/ADC5/TMS — Port F bit 5 / ADC channel 5 / JTAG test mode select |
| Pin 51 | PF4/ADC4/TCK — Port F bit 4 / ADC channel 4 / JTAG test clock |
| Pin 52 | PF3/ADC3 — Port F bit 3 / ADC channel 3 |
| Pin 53 | PF2/ADC2 — Port F bit 2 / ADC channel 2 |
| Pin 54 | PF1/ADC1 — Port F bit 1 / ADC channel 1 |
| Pin 55 | PF0/ADC0 — Port F bit 0 / ADC channel 0 |
| Pin 56 | GND — Ground |
| Pin 57 | VCC — Digital supply voltage |
| Pin 58 | PG5/OC0B — Port G bit 5 / timer 0 output compare B |
| Pin 59 | PG4/OC0A — Port G bit 4 / timer 0 output compare A |
| Pin 60 | PG3/TOSC2 — Port G bit 3 / timer oscillator pin 2 |
| Pin 61 | PG2/TOSC1 — Port G bit 2 / timer oscillator pin 1 |
| Pin 62 | PG1/RD — Port G bit 1 / external memory read strobe |
| Pin 63 | PG0/WR — Port G bit 0 / external memory write strobe |
| Pin 64 | PE0/RXD0/INT8 — Port E bit 0 / USART0 receive / external interrupt 8 |
Typical Applications
ATMEGA64L-8AI is suitable for 6 applications: Industrial Control and Factory Automation, Portable Battery-Powered Instruments, Medical Monitoring Devices, Building Automation and Smart Home Controllers, Motor Control Front-Ends, Legacy ATmega103 Board Upgrades.
Industrial Control and Factory Automation
The ATMEGA64L-8AI fits industrial control nodes because its 53 I/O lines, dual USARTs, and 8-channel 10-bit ADC can directly interface with sensors, relays, and fieldbus transceivers without external glue logic. Operating from 2.7 V to 5.5 V and rated -40C to +85C, it tolerates the wide supply and temperature swings of factory floors. In a typical node, the MCU samples analog process signals through the ADC, runs a control loop, and reports over RS-485 via a USART, while the 2 KB EEPROM stores calibration constants that survive power cycles. The trade-off is throughput: at 8 MHz the device delivers 8 MIPS, so compute-heavy motion control may need the 16 MHz ATMEGA64-16AU instead, which is pin compatible but requires at least 4.5 V.
Recommended
Portable Battery-Powered Instruments
The ATMEGA64L-8AI suits portable instruments because it operates down to 2.7 V, allowing direct connection to a single Li-ion cell or a 3-cell NiMH pack without a boost converter. Six sleep modes, a programmable watchdog timer, and brown-out detection let firmware trade active time for battery life, while the 64 KB Flash holds measurement algorithms and the 2 KB EEPROM logs calibration data. A handheld data logger might wake on a timer, sample the 10-bit ADC, store readings in 4 KB SRAM, and sleep again, drawing only microamps between bursts. The design consideration is clock accuracy: the internal RC oscillator is adequate for timing-insensitive tasks, but a crystal on the TOSC pins is needed when UART baud rates or real-time clocks must stay precise across temperature.
Recommended
Medical Monitoring Devices
The ATMEGA64L-8AI is used in medical monitoring front-ends where its 8-channel 10-bit ADC digitizes signals such as temperature, pressure, or pulse waveforms, and the dual USARTs stream results to a host or display module. The 2.7-5.5 V supply range supports both 3.3 V and 5 V analog rails, and the -40C to +85C rating covers clinical and home-health environments. In a patient monitor, the MCU runs an anti-aliasing filter loop, averages ADC samples in SRAM, and flags out-of-range values through a GPIO interrupt, while the watchdog timer forces recovery from firmware lockups. Because the ADC shares the AVCC supply, designers must decouple AVCC with a dedicated 100 nF capacitor and a ferrite bead to keep digital switching noise out of the measurement path.
Recommended
Building Automation and Smart Home Controllers
The ATMEGA64L-8AI serves building automation controllers that bridge sensors, actuators, and a network gateway. Its I2C (TWI) interface connects to temperature and humidity sensors, SPI drives external radio or memory modules, and the two USARTs link to a host gateway or a legacy RS-485 bus. With 53 I/O lines, a single MCU can manage multiple relay outputs and wall-switch inputs without port expanders, and the 2 KB EEPROM stores network addresses and scene configurations. The 8 MHz clock is sufficient for polling loops and simple control logic, but the design must budget Flash carefully: 64 KB fills quickly once a communication stack and OTA update routines are added, so the 4 KB SRAM should be reserved for packet buffers rather than large application arrays.
Recommended
Motor Control Front-Ends
The ATMEGA64L-8AI can act as a motor control front-end, generating PWM through its 8 PWM channels and reading position or current feedback on the 10-bit ADC. Two 16-bit timers provide the high-resolution PWM needed for smooth commutation, while the analog comparator and interrupt system enable fast overcurrent shutdown without CPU polling. In a brushed-DC or stepper controller, the MCU runs a PID loop at the PWM frequency, updates duty cycle registers, and reports status over a USART. The key trade-off is computational headroom: an 8 MHz AVR executes roughly 8 MIPS, which limits field-oriented control of three-phase motors, so designers typically pair the ATMEGA64L-8AI with an external gate driver and keep the control loop simple, or step up to the 16 MHz ATMEGA64-16AU for higher loop rates.
Recommended
Legacy ATmega103 Board Upgrades
The ATMEGA64L-8AI is a direct upgrade path for legacy ATmega103 designs because the ATmega64 family is 100% pin compatible with the ATmega103 and can replace it on existing printed circuit boards. Engineers migrating an old board gain 64 KB Flash, 4 KB SRAM, and 2 KB EEPROM in place of the ATmega103's smaller memory, plus JTAG debug that the older device lacked. Microchip application notes 'Replacing ATmega103 by ATmega128' and 'Migration between ATmega64 and ATmega128' document the firmware changes required, mainly register and interrupt-vector differences. The design consideration is voltage: if the legacy board runs at 5 V, the ATMEGA64L-8AI operates comfortably, but if it runs at 3.3 V, verify that the 8 MHz rating still meets timing margins for any external peripherals.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA64L-8AI — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA64L-8AU | ATMEGA64-16AU | ATMEGA64A-AU | ATMEGA64L-8AUR |
|---|---|---|---|---|---|
| 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 |
| Maximum Clock Frequency | 8 MHz | 8 MHz | 16 MHz | 16 MHz | 8 MHz |
| Operating Voltage | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 4.5 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB |
| EEPROM | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB |
| I/O Lines | 53 | 53 | 53 | 53 | 53 |
| ADC | 8-channel 10-bit | 8-channel 10-bit | 8-channel 10-bit | 8-channel 10-bit | 8-channel 10-bit |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Key Differentiators
- Low-voltage operation down to 2.7 V (vs ATMEGA64-16AU)
- 8 MHz rating guaranteed across full voltage range (vs ATMEGA64A-AU)
- Pin-compatible with legacy ATmega103 (vs ATMEGA64L-8AU)
- Integrated 2 KB EEPROM for calibration storage (vs ATMEGA64-16AU)
Design Notes
Decouple every VCC pin (pins 16, 34, 44, 57) with a 100 nF ceramic capacitor placed within 5 mm of the pin, and add a 10 uF bulk capacitor near the package. Supply AVCC (pin 47) through a separate ferrite bead or 10 ohm resistor with its own 100 nF capacitor to isolate ADC noise from digital switching. AREF (pin 46) should be bypassed with 100 nF to GND when using the internal reference, or driven from a low-impedance external reference for ratiometric measurements.
Route the crystal between XTAL1 (pin 14) and XTAL2 (pin 13) with traces shorter than 10 mm and guard them with ground. Keep the 22 pF load capacitors' ground returns directly to the MCU GND pins rather than to a shared analog ground plane. For the 64-TQFP package, use a thermal-relief-free ground pour under the device and connect all GND pins (17, 35, 45, 56) with short vias to the ground plane to minimize inductive bounce during ADC conversions.
The 8 MHz maximum frequency of the ATMEGA64L-8AI is guaranteed only across 2.7-5.5 V; do not assume the part can be overclocked at 5 V without checking the frequency-versus-voltage curve in the Microchip ATmega64/L datasheet. Also verify that the RESET pin (15) has an external pull-up of 10 kohm to VCC and a 100 nF capacitor to GND, since floating RESET can cause spurious resets in noisy industrial environments. Finally, confirm the JTAG fuse is disabled in production to free PF4-PF7 as ADC inputs.
Compliance Information
RoHS compliance and lead-free status are indicated by distributor listings for the ATMEGA64L-8AI. REACH, halogen-free, and conflict-minerals status were not stated in the provided web data and are marked unknown. The device is not AEC-Q100 qualified; it is rated for the industrial temperature range -40C to +85C.
