ATMEGA8L-8PU - 8-bit AVR MCU, 8KB Flash 8MHz | Microchip
MPN: ATMEGA8L-8PU ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.7 | $4.70 |
| 10 | $4.23 | $42.30 |
| 100 | $3.8 | $380.00 |
| 500 | $3.42 | $1,710.00 |
| 1,000 | $3.08 | $3,080.00 |
ATMEGA8L-8PU Overview
An 8-bit microcontroller (MCU) is a single integrated circuit that contains a processor core, memory, and programmable peripherals, forming the lowest tier of the embedded processing hierarchy: MCU -> embedded processor -> microprocessor system. The AVR family, originally developed by Atmel and now owned by Microchip Technology, uses an advanced RISC Harvard architecture in which most instructions execute in a single clock cycle, delivering up to 16 MIPS throughput at maximum clock speed.
Key features of the ATMEGA8L-8PU include 130 powerful instructions with mostly single-cycle execution, 32 general-purpose working registers, a fully static design, three flexible timer/counters with compare modes, and an internal 8-channel 10-bit A/D converter (6 channels on the PDIP package). The low-voltage L variant operates from 2.7V to 5.5V, making it suitable for battery-powered designs, with power-down mode current in the microampere range.
Technically, the device combines read-while-write ISP FLASH with on-chip debugging support via the SPI serial interface, plus a two-wire (I2C-compatible) interface, USART, and SPI peripherals. The AVR core executes from a single-level pipeline, keeping interrupt latency short and deterministic for real-time tasks.
Typical applications include hobbyist and educational boards (the part was long used in Arduino-class hardware), industrial sensor nodes, low-cost motor control, home automation, and small consumer appliances where 8KB of code space is sufficient.
Design consideration: choose the crystal frequency conservatively - the L-suffix part is limited to 8 MHz; overclocking above the rated speed grade violates the datasheet and reduces reliability across the 2.7V to 5.5V range.
This page adds value beyond the manufacturer datasheet by consolidating distributor pricing, drop-in replacement cross-references, pinout data, and practical design guidance in one place.
Drop-in alternatives for ATMEGA8L-8PU — 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 ATMEGA8L-8PU (same form factor and footprint) — differing in Instructions, Throughput, ADC, Communication Interfaces, Flash Memory.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA8A-PU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.86 / Unit
View Datasheet →ATMEGA8-16PI
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.85 / Unit
View Datasheet →ATMEGA88V-10PU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.3 / Unit
View Datasheet →ATMEGA88-20PI
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.85 / Unit
View Datasheet →ATMEGA328-PU
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA8L-8PU Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 8 KB (4K x 16) In-System Programmable |
| EEPROM | 512 B |
| SRAM | 1 KB |
| Maximum Clock Frequency | 8 MHz |
| Throughput | Up to 8 MIPS at 8 MHz (16 MIPS rating at 16 MHz for ATmega8 family) |
| Supply Voltage Range | 2.7 V to 5.5 V |
| General Purpose I/O | 23 programmable I/O lines |
| ADC | 8-channel 10-bit (6 channels available on PDIP) |
| Timers/Counters | Three (two 8-bit, one 16-bit) |
| Communication Interfaces | USART, SPI, 2-Wire (I2C-compatible) |
| Instructions | 130 instructions, mostly single-cycle |
| Working Registers | 32 x 8-bit general purpose |
| Package | 28-PDIP (0.300 in, 7.62 mm) |
| Mounting Type | Through-Hole |
| Operating Temperature | -40C to +85C (industrial, per FindIC IND TEMP listing) |
| Programming Interface | SPI In-System Programming (ISP) |
| RoHS Status | RoHS compliant (GREEN per FindIC) |
ATMEGA8L-8PU Pin Configuration
| Pin 1 | RESET (PC6) — Reset input; active-low, also usable as weak I/O when RSTDISBL fuse programmed |
| Pin 2 | PD0 (RXD) — Port D bit 0 / USART receive input |
| Pin 3 | PD1 (TXD) — Port D bit 1 / USART transmit output |
| Pin 4 | PD2 (INT0) — Port D bit 2 / External interrupt 0 |
| Pin 5 | PD3 (INT1) — Port D bit 3 / External interrupt 1 |
| Pin 6 | PD4 (T0) — Port D bit 4 / Timer0 external counter input |
| Pin 7 | VCC — Digital supply voltage (2.7 V to 5.5 V) |
| Pin 8 | GND — Ground |
| Pin 9 | PB6 (XTAL1/TOSC1) — Port B bit 6 / Crystal oscillator inverting input or timer oscillator input |
| Pin 10 | PB7 (XTAL2/TOSC2) — Port B bit 7 / Crystal oscillator output or timer oscillator output |
| Pin 11 | PD5 (T1) — Port D bit 5 / Timer1 external counter input |
| Pin 12 | PD6 (AIN0) — Port D bit 6 / Analog comparator positive input |
| Pin 13 | PD7 (AIN1) — Port D bit 7 / Analog comparator negative input |
| Pin 14 | PB0 (ICP1) — Port B bit 0 / Timer1 input capture |
| Pin 15 | PB1 (OC1A) — Port B bit 1 / Timer1 compare match A output (PWM) |
| Pin 16 | PB2 (SS/OC1B) — Port B bit 2 / SPI slave select, Timer1 compare match B output |
| Pin 17 | PB3 (MOSI/OC2) — Port B bit 3 / SPI master data out, Timer2 PWM output |
| Pin 18 | PB4 (MISO) — Port B bit 4 / SPI master data in |
| Pin 19 | PB5 (SCK) — Port B bit 5 / SPI serial clock |
| Pin 20 | AVCC — ADC supply voltage; connect to VCC via low-pass filter |
| Pin 21 | AREF — ADC reference voltage; decouple to GND when using internal reference |
| Pin 22 | GND — Ground |
| Pin 23 | PC0 (ADC0) — Port C bit 0 / ADC channel 0 |
| Pin 24 | PC1 (ADC1) — Port C bit 1 / ADC channel 1 |
| Pin 25 | PC2 (ADC2) — Port C bit 2 / ADC channel 2 |
| Pin 26 | PC3 (ADC3) — Port C bit 3 / ADC channel 3 |
| Pin 27 | PC4 (ADC4/SDA) — Port C bit 4 / ADC channel 4, 2-wire serial data |
| Pin 28 | PC5 (ADC5/SCL) — Port C bit 5 / ADC channel 5, 2-wire serial clock |
Typical Applications
ATMEGA8L-8PU is suitable for 6 applications: Hobby and Educational Embedded Platforms, Industrial Sensor Nodes, Battery-Powered Consumer Devices, Small Motor Control, Home Automation and Legacy IoT, Test Fixtures and Programming Adapters.
Hobby and Educational Embedded Platforms
The ATMEGA8L-8PU was a foundational part of early Arduino-class through-hole boards and remains a favorite in education because the 28-PDIP package is socketed, hand-solderable, and endlessly re-programmable via SPI ISP. Its 8KB FLASH and 1KB SRAM are large enough for full C programs using avr-gcc, while the single-cycle AVR core delivers 8 MIPS at 8 MHz for responsive I/O. The internal 1 MHz RC oscillator eliminates external components for simple projects, and the 6-channel 10-bit ADC reads sensors directly. Breadboard compatibility of the 0.3-inch DIP footprint shortens the learning loop from schematic to running firmware in minutes.
Recommended
Industrial Sensor Nodes
In industrial monitoring points, the ATMEGA8L-8PU combines a 10-bit ADC (6 channels on PDIP) with a 2.7V-5.5V supply range, allowing direct connection of potentiometers, NTC thermistors, and 4-20 mA conditioned signals without an external front end. The USART links to RS-485 transceivers for long-haul field buses, while the 2-wire interface reads EEPROM configuration memories. Power-down mode current in the microampere range suits duty-cycled nodes that wake on watchdog timer to sample and transmit. The industrial -40C to +85C temperature rating and the low-voltage L grade make it reliable across unregulated 5V plant supplies with brown-out protection enabled.
Recommended
Battery-Powered Consumer Devices
For battery products running from two or three cells, the ATMEGA8L-8PU's 2.7V floor permits operation directly from a declining lithium cell stack without a boost converter. Per the datasheet, active-mode consumption at 4 MHz and 3V is only a few milliamperes, and power-down mode drops to microampere levels, so a duty-cycled firmware design achieves multi-month battery life. The 512B EEPROM stores calibration and user settings without external nonvolatile memory. Timer2 can run from a 32.768 kHz watch crystal on XTAL1/XTAL2 for a real-time clock that keeps time even while the main core sleeps, a classic ATmega8 low-power pattern.
Recommended
Small Motor Control
The ATMEGA8L-8PU drives small DC and stepper motors using its three timer/counters: Timer1 provides a 16-bit PWM with output on PB1 (OC1A) and PB2 (OC1B), and Timer2 adds an 8-bit PWM on PB3 (OC2), enough for two-channel H-bridge control with direction and speed. The 23 I/O lines handle limit switches, encoders, and status LEDs with headroom. External interrupt INT0/INT1 on PD2/PD3 capture encoder pulses with low, deterministic latency thanks to the single-cycle AVR core. Its 2.7V-5.5V range shares the logic rail with common 5V gate-driver ICs, simplifying the power tree in appliance and robotics subassemblies.
Recommended
Home Automation and Legacy IoT
Legacy home-automation nodes built around the ATMEGA8L-8PU still ship today: the 2-wire interface talks to I2C sensors and RTCs, the USART interfaces RF modules such as nRF24L01+ (via SPI actually - SPI on PB3-PB5) and serial radio bridges, and 6 ADC channels read wall-mounted controls. The socketed PDIP footprint simplifies field firmware updates - swap the chip or reflash via ISP header without desoldering. Designers extending these products typically migrate to the pin-compatible ATMEGA328-PU for 32KB FLASH to host larger protocol stacks, keeping the PCB unchanged. Brown-out detection and watchdog timer provide autonomous recovery in unattended installations.
Recommended
Test Fixtures and Programming Adapters
The ATMEGA8L-8PU is widely embedded in AVR programmers, test jigs, and USB-serial bridges because the SPI ISP hardware can bit-bang or generate target clocks, and the USART provides straightforward host communication. Its 8 KB FLASH comfortably holds interpreter-style fixture firmware, and the EEPROM keeps calibration constants per fixture. The 5V-tolerant through-hole DIP survives repeated handling in production environments better than fine-pitch SMD alternatives, and a socket allows instant firmware revision swaps. At 8 MHz the device balances enough throughput for fixture sequencing with the low EMI of a modest clock rate.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA8L-8PU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA8A-PU | ATMEGA8-16PI | ATMEGA88V-10PU | ATMEGA88-20PI | ATMEGA328-PU |
|---|---|---|---|---|---|---|
| Package | 28-PDIP (0.300 in) | 28-PDIP - same | 28-PDIP - same | 28-PDIP - same | 28-PDIP - same | 28-PDIP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB | 32 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 1 KB | 1 KB | 2 KB |
| Supply Voltage | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 4.5 V to 5.5 V | 1.8 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V (P: 1.8 V) |
| Maximum Clock Speed | 8 MHz | 16 MHz | 16 MHz | 10 MHz | 20 MHz | 20 MHz |
| Register/Firmware Compatibility | ATmega8 baseline | Code-compatible (recompile recommended) | Fully code-compatible | Recompile required (ATmega88 map) | Recompile required (ATmega88 map) | Recompile required (ATmega328P map) |
| Lifecycle Status | Active (ATMEGA8A recommended for new designs) | Active - recommended successor | Active (mature) | Active | Active | Active |
Key Differentiators
- True low-voltage operation down to 2.7 V (vs ATMEGA8-16PI)
- Code-compatible migration path to a newer die (vs ATMEGA8A-PU)
- Socketed through-hole PDIP vs SMD-only equivalents (vs ATMEGA8L-8MU)
Design Notes
Decouple VCC and AVCC separately: place a 100 nF ceramic directly at pin 7 and another at pin 20, plus 10 uF bulk at the board supply entry. AVCC should connect to VCC through an LC or RC low-pass filter (e.g., 10 uH + 100 nF) when the ADC is used, because digital switching noise on AVCC directly degrades 10-bit ADC accuracy. If ADC is not used, the datasheet permits tying AVCC directly to VCC. Enable brown-out detection via fuse at ~2.7 V for the L-grade part to prevent FLASH corruption during supply sag.
The ATMEGA8L-8PU defaults to the internal 1 MHz RC oscillator, not 8 MHz - if your code assumes 8 MHz timing (UART baud, delays), program the CKOPT/fuse bits for an external crystal or the correct internal calibration. Also, RESET (pin 1) must not be left floating in noisy environments; a 10k pull-up to VCC improves immunity and keeps the ISP pin state defined. Do not exceed the 8 MHz speed grade at low voltage - consult the frequency-versus-VCC curve in the family datasheet before overclocking any L-suffix part.
For the through-hole PDIP, keep the crystal (if used) within 1 cm of pins 9 and 10 with 22 pF load capacitors to ground, and route a short ground return. Decouple AREF with a 100 nF capacitor to ground when using the internal 2.56 V reference, and never drive AREF while the internal reference is enabled. If migrating later to an ATMEGA88 or ATmega328 drop-in, reserve a 6-pin ISP header on MOSI/MISO/SCK/RESET - all alternatives in this comparison share the same ISP pin assignment.
Compliance Information
FindIC product record lists ATMEGA8L-8PU as GREEN (RoHS/lead-free) industrial-temperature PDIP. The -PI suffix variant is the older leaded industrial finish. REACH, halogen-free, and conflict-minerals status not stated in provided data.
