ATMEGA64L-8AC - 8-bit AVR MCU, 64KB Flash, 8MHz | Microchip
MPN: ATMEGA64L-8AC ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.2 | $7.20 |
| 10 | $6.48 | $64.80 |
| 100 | $5.76 | $576.00 |
| 500 | $5.18 | $2,590.00 |
| 1,000 | $4.61 | $4,610.00 |
ATMEGA64L-8AC Overview
An AVR ATmega microcontroller is an 8-bit Harvard-architecture RISC MCU in the broader hierarchy of microcontrollers within the semiconductor device family. The ATmega64 family member executes most of its 130 powerful instructions in a single clock cycle, achieving up to 16 MIPS throughput at 16MHz, with 32 general purpose working registers directly connected to the ALU. It descends from the ATmega103, to which it is 100% pin compatible, allowing direct replacement on existing PCBs.
Key features include 53 general purpose I/O lines, four flexible Timer/Counters with compare modes and PWM, two USARTs for serial communication, a byte-oriented Two-Wire Serial Interface (TWI/I2C), an SPI serial port, and a JTAG interface for on-chip debugging. The 64KB self-programming Flash supports Read-While-Write operation, enabling bootloader firmware updates in the field. The integrated Real Time Counter (RTC) with separate oscillator supports low-power timekeeping, and the brown-out detector plus internal RC oscillator reduce external component count.
The AVR core combines a rich instruction set with low power consumption, making the ATmega64L suitable for designs where both code density and energy efficiency matter. The L suffix and AC grade denote 8MHz maximum clock speed across a 2.7V to 5.5V operating range at commercial temperature ratings.
Typical applications include industrial control panels, embedded instrumentation, battery-powered data loggers, building automation nodes, and legacy ATmega103 system upgrades, where dual USARTs and the 10-bit ADC cover most sensing and communication needs without external peripherals.
Design consideration: the ATmega64L-8AC is speed-limited to 8MHz; the ATmega64-16AU variant should be selected when 16MHz throughput is required at 4.5V to 5.5V.
This page synthesizes distributor pricing, drop-in alternatives, design notes, and cross-reference data not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA64L-8AC — 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-8AC (same form factor and footprint) — differing in Timers/Counters, Package, EEPROM, RoHS Status, ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA64A-AUR
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →ATMEGA64-16AU
✅ Drop-In✓ In Stock
$7.23 / Unit
View Datasheet →ATMEGA64L-8AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.55 / Unit
View Datasheet →ATMEGA128L-8AU
✅ Drop-In✓ In Stock
$23.49 / Unit
View Datasheet →ATMEGA64A-AUR
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.1 / Unit
View Datasheet →ATMEGA64L-8AC Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Flash Program Memory | 64 KB (32K x 16) In-System Programmable |
| EEPROM | 2 KB |
| SRAM | 4 KB |
| Maximum Clock Frequency | 8 MHz |
| Operating Voltage Range | 2.7 V to 5.5 V |
| General Purpose I/O | 53 lines |
| ADC | 8-channel, 10-bit |
| USART | 2 |
| Timers/Counters | 4 with compare modes and PWM |
| Serial Interfaces | TWI (I2C-compatible), SPI, 2x USART |
| Debug Interface | JTAG for on-chip debug |
| Real Time Counter | Yes (RTC) |
| Package | 64-TQFP (14x14 mm) |
| Mounting Type | Surface Mount |
| Instruction Set | 130 instructions, most single-cycle |
| Throughput | Up to 16 MIPS at 16 MHz |
| Operating Temperature Grade | Commercial (AC grade) |
| Pin Compatibility | 100% pin compatible with ATmega103 |
ATMEGA64L-8AC 64-tqfp (14x14 mm) Pin Configuration Guide
Pin configuration for ATMEGA64L-8AC (64-tqfp (14x14 mm) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for ATMEGA64L-8AC.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA64L-8AC is suitable for 6 applications: Industrial Control Panels, Legacy ATmega103 System Upgrades, Battery-Powered Data Loggers, Building Automation Nodes, Embedded Instrumentation, Motor Control and PWM Applications.
Industrial Control Panels
The ATMEGA64L-8AC fits industrial control panels because its 53 GPIO lines, four Timer/Counters with compare and PWM modes, and two independent USARTs cover relay driving, keypad scanning, and RS-485/MODBUS communication through external transceivers in a single 64-TQFP device. The 8-channel 10-bit ADC digitizes analog sensor inputs such as level and pressure transmitters at up to 10-bit resolution without an external converter. The 2.7V to 5.5V operating range allows direct operation from 5V industrial logic rails, and the 64KB self-programming Flash enables field firmware updates via bootloader for control-logic revisions. The JTAG interface provides on-chip debugging during commissioning, reducing development iterations.
Recommended
Legacy ATmega103 System Upgrades
The ATmega64 is 100% pin compatible with the ATmega103, making the ATMEGA64L-8AC the canonical drop-in upgrade for legacy ATmega103-based printed circuit boards, according to the Atmel ATmega64/L datasheet. The upgrade path delivers an enhanced AVR core with 130 mostly single-cycle instructions, JTAG on-chip debugging, doubled EEPROM (2KB), and self-programming Flash that the ATmega103 lacked. Existing firmware requires only minor recompilation; Atmel application notes document migration considerations between the two families. Because the same TQFP-64 footprint is retained, boards do not need respinning, protecting investment in long-life industrial and test equipment designs still in service.
Recommended
Battery-Powered Data Loggers
The ATMEGA64L-8AC suits battery-powered data logging because the L speed grade operates down to 2.7V, allowing the MCU to run directly from three AA cells or a single lithium cell with a simple regulator, maximizing usable battery capacity. The integrated Real Time Counter with a 32kHz crystal provides low-power timekeeping while the main core sleeps, and the 4KB SRAM buffers measurement samples between power-hungry flash writes to the 2KB EEPROM or external storage. The 8-channel 10-bit ADC acquires multiple sensor channels such as temperature, humidity, and voltage without external front-ends. Dual USARTs allow simultaneous local logging and radio or cellular modem communication in remote monitoring deployments.
Recommended
Building Automation Nodes
In building automation, the ATMEGA64L-8AC serves as a node controller handling sensor acquisition, actuator control, and network communication on a single chip. The byte-oriented Two-Wire Serial Interface (TWI, I2C-compatible) connects digital temperature, humidity, and light sensors, while the SPI port interfaces with external flash or displays. The 10-bit ADC covers 0-10V conditioned analog inputs via resistor dividers, and four PWM-capable timers drive damper motors or LED dimming. The 64KB Flash accommodates protocol stacks and configuration tables, and self-programming capability allows remote firmware maintenance over the network. Commercial temperature grading (AC) matches indoor controller environments.
Recommended
Embedded Instrumentation
Bench and field instrumentation benefit from the ATMEGA64L-8AC combination of JTAG on-chip debugging, 64KB program memory, and dual USARTs. One USART can drive a host interface or printer while the second handles module-to-module communication, eliminating a separate UART IC. The 10-bit ADC with 8 channels digitizes front-end outputs, and Timer/Counter capture modes measure frequency and pulse width for measurement functions. The 4KB SRAM supports display buffers and averaging windows, while the 32 general purpose registers and single-cycle execution keep interrupt latency low for responsive user interfaces with rotary encoders and LCD panels. Bootloader capability supports firmware updates in deployed instruments.
Recommended
Motor Control and PWM Applications
The ATMEGA64L-8AC addresses small motor control tasks with its four Timer/Counters providing compare channels and phase-correct or fast PWM outputs at up to 8MHz clock resolution, sufficient for DC motor speed control, servo driving, and stepper sequencing through external MOSFET gate drivers. The 10-bit ADC reads back current-sense shunts and potentiometer position feedback, enabling closed-loop control implemented entirely in firmware. Two USARTs allow command interfaces to a supervisory controller. The wide 2.7V to 5.5V supply range lets logic run from the same 5V rail as gate drivers, simplifying board design. The 64KB Flash retains ample space for control tables and communication stacks.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA64L-8AC — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA64A-AUR | ATMEGA64-16AU | ATMEGA64L-8AU | ATMEGA128L-8AU |
|---|---|---|---|---|---|
| Package | 64-TQFP (14x14) | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 128 KB |
| Max Clock Frequency | 8 MHz | 16 MHz | 16 MHz | 8 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 (full speed) | 2.7 V to 5.5 V | 2.7 V to 5.5 V |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB |
| Temperature Grade | Commercial (AC) | Industrial (AU) | Industrial (AU) | Industrial (AU) | Industrial (AU) |
| Pin Compatibility | Pin compatible with ATmega103 / ATmega64 family | Pin-to-pin identical | Pin-to-pin identical | Pin-to-pin identical | Pin-to-pin identical (per Atmel migration note) |
Key Differentiators
- Low-voltage operation down to 2.7V (vs ATMEGA64-16AU)
- JTAG on-chip debug on a 64KB AVR (vs ATmega103 (predecessor))
- Memory-identical refresh at same cost tier (vs ATMEGA64A-AUR)
Design Notes
Decouple VCC and AVCC independently with 0.1uF ceramic capacitors placed close to the respective pins, and connect AVCC to VCC through a low-pass LC filter when using the ADC, since the 10-bit converter accuracy depends directly on AVCC ripple. The 8MHz L-grade device can run from a 3.3V rail; note that maximum safe clock speed is voltage-dependent for AVR devices, so if migrating to a 16MHz ATmega64 variant, full speed requires 4.5V to 5.5V. Estimated: a 5V rail with 10mA MCU load draws 50mW, well within typical battery budgets for logger applications.
For the 64-TQFP (14x14 mm) package, use a 0.5mm pitch fanout with 0.25mm vias on escape routing; the package is hand-solderable with practice but reflow is recommended. Keep the JTAG (TCK/TMS/TDO/TDI) header on the PCB even in production builds - the on-chip debug capability is a major advantage of ATmega64 over smaller ATmega parts. Reserve footprint compatibility by designing the land pattern to also accept the ATmega128 TQFP-64, which enables a memory upgrade without respin, per the Atmel migration application note.
Do not confuse the AC (commercial) temperature grade with industrial AU/AI grades when specifying for harsh environments - the suffix matters for reliability qualifications. The L-grade device is limited to 8MHz; attempting 16MHz operation risks out-of-specification behavior. Also note the ATmega64 to ATmega128 migration is not transparent: interrupt vector tables and extended addressing differ, so follow the Atmel application note on migration between ATmega64 and ATmega128 before swapping in a 128KB part. Always set fuse bits for external crystal operation carefully - wrong fuse settings can disable further ISP access.
Compliance Information
Compliance data not present in the verified sources for this exact MPN suffix. Microchip ATmega64A refresh variants are produced in RoHS green packaging; verify certificates on the Microchip product page before RoHS-regulated designs.
