ATMEGA4809-AFR - 8-bit AVR MCU 20MHz 48KB Flash TQFP-48 | Microchip
MPN: ATMEGA4809-AFR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.1 | $2.10 |
| 10 | $1.89 | $18.90 |
| 100 | $1.68 | $168.00 |
| 500 | $1.52 | $760.00 |
| 1,000 | $1.36 | $1,360.00 |
ATMEGA4809-AFR Overview
An 8-bit microcontroller (MCU) is an integrated circuit that contains a processor core, memory, and programmable input/output peripherals on a single chip, executing one instruction per cycle over 8-bit data words. Within the power and control hierarchy of embedded systems, MCUs sit at the application layer beneath system-on-chip devices, handling real-time control, sensing, and communication tasks in everything from appliances to industrial automation.
Key features of the ATMEGA4809-AFR include Core Independent Peripherals (CIPs) that operate without CPU intervention, a 10-bit ADC, analog comparators, and multiple serial interfaces including UART, SPI, and I2C/TWI. The AVR core with hardware multiplier delivers efficient 8-bit computation, while low-power features such as sleep modes and event system routing reduce energy consumption in battery-operated designs.
Technically, the megaAVR 0-series uses an enhanced AVR RISC architecture with a single-cycle instruction execution model and an event system that allows peripherals to signal each other directly. The 48 KB self-programmable Flash supports in-system programming via UPDI (Unified Program and Debug Interface), simplifying production and field updates.
Typical applications include Arduino-compatible boards (the Arduino Nano Every uses the ATmega4809), industrial control and sensing nodes, home appliances, and touch-sensing interfaces with the integrated Peripheral Touch Controller.
A key design consideration is supply voltage: the device operates at 3.3V or 5V logic levels, and Flash endurance plus ADC accuracy depend on operating voltage and temperature ranges specified in the datasheet.
This page synthesizes distributor data, drop-in alternatives within the megaAVR 0-series family, pinout information, and practical design notes not found in the manufacturer datasheet, providing comparison and sourcing context as of 2026-09-18.
Drop-in alternatives for ATMEGA4809-AFR β 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 ATMEGA4809-AFR (same form factor and footprint) β differing in SRAM, Operating Temperature, Package, Series, Connectivity.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA4809-AUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA4809-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA4809-AF
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$1.92 / Unit
View Datasheet βATMEGA4809-AN
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA4809-AFR Maximum Ratings & Electrical Characteristics
| Core | AVR 8-bit |
| Core Size | 8-bit |
| Series | megaAVR 0 |
| Maximum Clock Frequency | 20 MHz |
| Program Memory Size | 48 KB (48K x 8) Flash |
| SRAM Size | 6 KB |
| EEPROM Size | 256 B |
| Supply Voltage | 1.8 V to 5.5 V (3.3V/5V operation) |
| Data Bus Width | 8 bit |
| Programmability | UPDI (Unified Program and Debug Interface) |
| Peripheral Features | Core Independent Peripherals (CIP), 10-bit ADC, event system, Peripheral Touch Controller |
| Communication Interfaces | UART, SPI, I2C/TWI |
| Package / Case | TQFP-48 (7x7 mm) |
| Mounting Style | SMD/SMT |
| Operating Temperature | -40C to +105C |
| Packaging | Tape & Reel (R suffix) |
| Functional Safety | FuSa variant per DigiKey listing |
| RoHS Status | Compliant |
ATMEGA4809-AFR Pin Configuration
| Pin 1 | PB5 β Port B bit 5 (GPIO/analog) |
| Pin 2 | PB4 β Port B bit 4 (GPIO/analog) |
| Pin 3 | PB3 β Port B bit 3 (GPIO/analog) |
| Pin 4 | PB2 β Port B bit 2 (GPIO/analog) |
| Pin 5 | PB1 β Port B bit 1 (GPIO/analog) |
| Pin 6 | PB0 β Port B bit 0 (GPIO/analog, analog comparator inputs) |
| Pin 7 | GND β Ground |
| Pin 8 | VDD β Power supply (1.8V to 5.5V) |
| Pin 9 | PC7 β Port C bit 7 (GPIO) |
| Pin 10 | PC6 β Port C bit 6 (GPIO) |
| Pin 11 | PC5 β Port C bit 5 (GPIO/USART alt) |
| Pin 12 | PC4 β Port C bit 4 (GPIO/USART alt) |
| Pin 13 | PC3 β Port C bit 3 (GPIO) |
| Pin 14 | PC2 β Port C bit 2 (GPIO) |
| Pin 15 | PC1 β Port C bit 1 (GPIO) |
| Pin 16 | PC0 β Port C bit 0 (GPIO) |
| Pin 17 | PD7 β Port D bit 7 (GPIO/analog) |
| Pin 18 | PD6 β Port D bit 6 (GPIO/analog) |
| Pin 19 | PD5 β Port D bit 5 (GPIO/analog) |
| Pin 20 | PD4 β Port D bit 4 (GPIO/analog) |
| Pin 21 | PD3 β Port D bit 3 (GPIO/analog) |
| Pin 22 | PD2 β Port D bit 2 (GPIO/analog) |
| Pin 23 | PD1 β Port D bit 1 (GPIO/analog) |
| Pin 24 | PD0 β Port D bit 0 (GPIO/analog) |
| Pin 25 | PE3 β Port E bit 3 (GPIO) |
| Pin 26 | PE2 β Port E bit 2 (GPIO) |
| Pin 27 | PE1 β Port E bit 1 (GPIO) |
| Pin 28 | PE0 β Port E bit 0 (GPIO) |
| Pin 29 | GND β Ground |
| Pin 30 | VDD β Power supply (1.8V to 5.5V) |
| Pin 31 | PF7 β Port F bit 7 (GPIO/analog) |
| Pin 32 | PF6 β Port F bit 6 (GPIO/analog) |
| Pin 33 | PF5 β Port F bit 5 (GPIO/analog) |
| Pin 34 | PF4 β Port F bit 4 (GPIO/analog) |
| Pin 35 | PF3 β Port F bit 3 (GPIO/analog) |
| Pin 36 | PF2 β Port F bit 2 (GPIO/analog) |
| Pin 37 | PF1 β Port F bit 1 (GPIO/analog) |
| Pin 38 | PF0 β Port F bit 0 (GPIO/analog) |
| Pin 39 | PA7 β Port A bit 7 (GPIO/analog) |
| Pin 40 | PA6 β Port A bit 6 (GPIO/analog) |
| Pin 41 | PA5 β Port A bit 5 (GPIO/analog) |
| Pin 42 | PA4 β Port A bit 4 (GPIO/analog) |
| Pin 43 | PA3 β Port A bit 3 (GPIO/analog) |
| Pin 44 | PA2 β Port A bit 2 (GPIO/analog) |
| Pin 45 | PA1 β Port A bit 1 (GPIO/analog) |
| Pin 46 | PA0 β Port A bit 0 (GPIO/analog, external clock option) |
| Pin 47 | UPDI β Unified Program and Debug Interface |
| Pin 48 | VDD β Power supply (1.8V to 5.5V) |
Typical Applications
ATMEGA4809-AFR is suitable for 6 applications: Arduino-Compatible Development Boards, Industrial Control and Automation Nodes, Capacitive Touch User Interfaces, Home Appliance Control, Sensor Acquisition and IoT Edge Nodes, Educational and Prototyping Platforms.
Arduino-Compatible Development Boards
The ATmega4809 is the MCU at the heart of the Arduino Nano Every and Arduino Uno WiFi Rev2, making the ATMEGA4809-AFR a natural choice for custom Arduino-compatible hardware. Its 48 KB Flash and 6 KB SRAM roughly double the ATmega328P budget, so larger sketches, buffers, and libraries fit without optimization gymnastics. The UPDI single-wire interface simplifies bootloader and debug wiring on small boards. Native Arduino IDE support plus the community MegaCoreX package (which defines the full 48-pin-standard variant pinout) accelerate bring-up. Designers should verify that any Nano Every-derived circuit matches the official reference design, since compatible boards differ in USB bridge and regulator topology.
Recommended
Industrial Control and Automation Nodes
With an industrial -40C to +105C operating range, Core Independent Peripherals, and a 20 MHz AVR core with hardware multiplier, the ATMEGA4809-AFR fits industrial sensor nodes, motor-control adjuncts, and actuator interfaces. The event system routes timer, comparator, and ADC signals directly between peripherals, keeping control loops deterministic even when the CPU is servicing communication. Multiple UART, SPI, and TWI interfaces support Modbus-style fieldbus links and sensor aggregation. The 5V-compatible I/O simplifies interfacing with legacy 24V-logic-adjacent industrial circuitry through level shifting. Designers should budget Flash endurance and use the 256-byte EEPROM for configuration storage with wear-leveling awareness.
Recommended
Capacitive Touch User Interfaces
The integrated Peripheral Touch Controller (PTC) on the ATMEGA4809-AFR enables capacitive touch buttons, sliders, and wheels without a dedicated touch IC, reducing BOM cost in appliance panels and consumer controls. Combined with Core Independent Peripherals, touch acquisition can run in hardware-assisted cycles while the CPU sleeps between scans, cutting average current in always-on interfaces. The 48-pin TQFP offers up to 41 GPIO, enough for touch electrodes plus LED feedback and UART links to a main controller. Microchip provides touch tuning tools and application notes to optimize sensitivity and EMC robustness; follow the recommended ground-plane and electrode layout guidelines in the datasheet for reliable water-tolerant performance.
Recommended
Home Appliance Control
Appliance control boards benefit from the ATMEGA4809-AFR's combination of 48 KB self-programmable Flash, -40C to +105C industrial temperature rating, and 5V-tolerant peripheral set. The 10-bit ADC reads thermistors and potentiometers, analog comparators protect against over-current conditions in hardware, and the event system lets a timer trip PWM outputs without CPU latency for motor or heater control. The 256-byte EEPROM stores calibration and user settings across power cycles. UPDI programming enables in-field firmware updates through a single wire routed to a service connector, reducing service cost. Its Core Independent Peripherals and low-power sleep modes also suit battery-backup standby circuits where a few microamps matter.
Recommended
Sensor Acquisition and IoT Edge Nodes
For battery-powered sensor nodes, the ATMEGA4809-AFR pairs its 20 MHz compute headroom with low-power features: sleep modes, peripheral operation independent of the CPU, and the event system that can capture an ADC result on a timer trigger while the core sleeps. Six kilobytes of SRAM accommodates ring buffers for burst sensor data and lightweight protocol stacks, while 48 KB Flash holds application plus OTA-updatable firmware. UART, SPI, and TWI interfaces connect radios, MEMS sensors, and external EEPROMs directly. Designers should profile sleep-mode currents against datasheet electrical characteristics and size the 10-bit ADC front-end filtering per application note guidance to balance noise, speed, and energy per sample.
Recommended
Educational and Prototyping Platforms
The ATMEGA4809-AFR is well suited to university labs and maker prototyping because it bridges classic AVR teaching material and modern peripherals: students can program it through Arduino IDE (Nano Every target) or MegaCoreX, while learning Core Independent Peripherals, the event system, and UPDI debugging that mirror industry practice in Microchip's newer families. The 48-pin TQFP is hand-solderable on adapter boards or inexpensive TQFP-48 footprints, and single-wire UPDI needs only a low-cost programmer. Six kilobytes of SRAM prevents early frustration with memory limits, and the hardware multiplier enables fixed-point DSP exercises. Reference designs and community libraries further lower the entry barrier for coursework and rapid breadboard-to-PCB iterations.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA4809-AFR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA4809-AUR | ATMEGA4809-AU | ATMEGA4809-AF | ATMEGA4809-AN |
|---|---|---|---|---|---|
| Package | TQFP-48 (7x7 mm) | TQFP-48 - same | TQFP-48 - same | TQFP-48 - same | TQFP-48 - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 48 KB | 48 KB | 48 KB | 48 KB | 48 KB |
| SRAM | 6 KB | 6 KB | 6 KB | 6 KB | 6 KB |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Temperature | -40C to +105C | -40C to +105C | -40C to +105C | 0C to +70C (commercial) | -40C to +105C |
| Packaging Format | Tape & Reel | Tape & Reel | Tray | Tray | Tray |
| Programming Interface | UPDI | UPDI | UPDI | UPDI | UPDI |
Key Differentiators
- Double the memory of classic ATmega parts (vs ATMEGA328PB-MU)
- Single-wire UPDI programming (vs ATMEGA32A-AU)
- Industrial temperature with reel packaging (vs ATMEGA4809-AF)
Design Notes
Place 100 nF ceramic decoupling capacitors directly across each VDD/GND pair (pins 7/8 and 29/30, plus pin 48), with short, low-inductance traces to the ground plane. The TQFP-48 7x7 mm footprint has a 0.5 mm pin pitch - use solder-mask-defined pads per IPC-recommended TQFP land patterns and verify paste aperture reduction to avoid bridging on reflow. Route the UPDI pin to a 3-pad or Tag-Connect footprint for in-system programming; keep it free of strong pull-ups that could interfere with UPDI communication.
The ATMEGA4809-AFR operates from 1.8V to 5.5V, but clock frequency and Flash write reliability are voltage-dependent: consult the electrical characteristics tables in datasheet DS40002173B before running 20 MHz near the low-voltage corner. Estimated: at 5 V and moderate I/O loading, core current is in the low milliamp range; size the 3.3 V or 5 V regulator with margin for I/O currents driving LEDs or buses. Add bulk capacitance (4.7 uF to 10 uF) near the supply pins alongside the 100 nF decoupling.
Three common pitfalls: (1) Do not confuse the R (tape-and-reel) suffix ordering with prototype quantities - reels are typically 3000+ pieces; order -AU tray units for development. (2) Migrating from ATmega328P-style ISP to ATmega4809 requires a UPDI programmer; SPI ISP hardware will not work. (3) Per the datasheet, on 40-pin variants PB5:0 and PC7:6 must be disabled or pulled up; this does not apply to the 48-pin ATMEGA4809-AFR, but code ported from 40-pin designs should be reviewed for pin-mapping assumptions.
Compliance Information
RoHS compliance per Microchip product listing for ATMEGA4809-AFR (standard green/RoHS package option). REACH, halogen-free, and conflict-minerals status not stated in the retrieved web data - verify on the Microchip product page.
