ATMEGA4809-MUR - 8-Bit AVR MCU 20MHz 48KB Flash | Microchip
MPN: ATMEGA4809-MUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.62 | $1.62 |
| 10 | $1.46 | $14.60 |
| 100 | $1.24 | $124.00 |
| 500 | $1.05 | $525.00 |
| 1,000 | $0.92 | $920.00 |
ATMEGA4809-MUR Overview
An 8-bit microcontroller is an integrated circuit that combines a processor core, program memory, data memory and peripherals on a single chip, sitting at the device level of the embedded-systems hierarchy (semiconductor -> IC -> microcontroller -> 8-bit MCU). MCUs execute control firmware for sensing, actuation and communication tasks, and the megaAVR 0 series is the successor family to the classic ATmega328P used in Arduino boards.
Key features include the AVR RISC core with a hardware multiplier executing most instructions in a single cycle at up to 20 MHz, Core Independent Peripherals (CIPs) that operate without CPU intervention, and low-power features for battery-operated designs. The 48 KB Flash (organized as 24K x 16) provides generous code space, while 6 KB SRAM supports larger buffers and stacks than legacy ATmega328-class parts.
Architecturally, the ATmega4809 integrates multiple TCA/TCB timers, USARTs, SPI and TWI (I2C) interfaces, a 10-bit ADC, analog comparators and configurable custom logic cells, enabling event-driven designs in which peripherals communicate directly via the event system. The wide 2.5 V / 3.3 V / 5 V supply compatibility simplifies migration from 5 V legacy AVR designs to 3.3 V systems.
Typical applications include industrial control and automation nodes, Arduino Nano Every-class maker and educational platforms, and consumer appliances requiring robust 8-bit control with safety documentation.
A key design consideration: the 48-pin UQFN 6x6 package has fine pitch, so verify the PCB land pattern against the Microchip datasheet and use adequate via stitching on the exposed pad for grounding.
This page synthesizes verified distributor data, drop-in family alternatives, and practical design notes not found on the manufacturer product page.
Drop-in alternatives for ATMEGA4809-MUR 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-MUR (same form factor and footprint) β differing in Package, RoHS Status, Series, Connectivity, Core Processor.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA4808-MUR
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$1.22 / Unit
View Datasheet βATMEGA3209-MUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA4809-AUR
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA4809-MUR Maximum Ratings & Electrical Characteristics
| Core | AVR 8-bit RISC |
| Core Size | 8-bit |
| Maximum Clock Frequency | 20 MHz |
| Program Memory Size | 48 KB (24K x 16) Flash |
| SRAM Size | 6 KB |
| EEPROM Size | 256 bytes |
| Supply Voltage | 2.5 V / 3.3 V / 5 V |
| Series | megaAVR 0, Functional Safety (FuSa) |
| Package | 48-UQFN (6x6 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (TR) |
| Hardware Multiplier | Yes |
| Peripheral Features | Core Independent Peripherals (CIPs), low power features |
| Product Status | Active |
| RoHS Status | Compliant (per DigiKey listing) |
ATMEGA4809-MUR 48-uqfn (6x6 mm) with exposed pad Pin Configuration Guide
Pin configuration for ATMEGA4809-MUR (48-uqfn (6x6 mm) with exposed pad 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 ATMEGA4809-MUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA4809-MUR is suitable for 6 applications: Industrial Control and Automation Nodes, Arduino-Compatible Maker and Educational Platforms, Consumer Appliance Control Boards, Sensor Hubs and IoT Edge Nodes, Motor Control and Lighting Systems, Legacy ATmega Design Migration and BOM Continuity.
Industrial Control and Automation Nodes
The ATMEGA4809-MUR fits industrial control nodes where deterministic 8-bit control and safety documentation are required: its 20 MHz AVR core executes most instructions in a single cycle, giving predictable interrupt latency, while its Functional Safety (FuSa) classification under the megaAVR 0 series supports IEC 61508-style development flows. With 48 KB of Flash there is room for communication stacks (Modbus over USART, or TWI sensor buses) plus diagnostic code, and the 6 KB SRAM accommodates ring buffers for multi-node networks. Core Independent Peripherals can run PWM generation and serial links while the CPU sleeps, and the event system routes peripheral signals without software overhead. Designers typically pair it with an external supervisor and use the internal watchdog for fault containment.
Recommended
Arduino-Compatible Maker and Educational Platforms
The ATmega4809 is the MCU inside the Arduino Nano Every and Arduino Uno WiFi Rev2, making the ATMEGA4809-MUR the natural chip-level choice for custom Nano Every-compatible boards. Compared with the legacy ATmega328P, it offers 48 KB Flash versus 32 KB, 6 KB SRAM versus 2 KB, and a hardware multiplier, which together allow larger sketches, deeper stacks and faster math. First-party Arduino core support plus the community MegaCoreX package on GitHub provide board definitions for the 48-pin-standard variant, and programming is done over single-wire UPDI with an Atmel-ICE or UPDI bridge. The 2.5-5 V supply range matches common breadboard and battery supplies, keeping student and maker designs simple and robust.
Recommended
Consumer Appliance Control Boards
White-goods and small-appliance control boards benefit from the ATMEGA4809-MUR's combination of 5 V direct operation, 48 KB Flash for button-debounce state machines, display drivers and communication protocols, and low-power sleep modes for standby compliance. The Core Independent Peripherals can continue driving triac or relay PWM and scanning a keypad matrix while the CPU rests, reducing energy consumption in standby. The UQFN 6x6 mm exposed-pad package keeps the controller footprint small on cost-driven two-layer boards, and tape-and-reel packing (the MUR suffix) suits high-volume pick-and-place assembly. Migration from older ATmega parts is straightforward because the AVR instruction set and AVR-GCC toolchain are shared across the family.
Recommended
Sensor Hubs and IoT Edge Nodes
As a sensor hub, the ATMEGA4809-MUR aggregates I2C (TWI) and SPI sensor streams into a single UART or wireless module link. Its 10-bit ADC samples analog sensors directly, the analog comparators provide threshold alarms without CPU involvement, and the event system chains peripherals for autonomous acquisition. The 6 KB SRAM supports modest data logging and packet assembly, while 48 KB Flash holds a full protocol stack plus OTA-style update code. Operating from 2.5 V to 5 V allows direct connection to Li-ion-regulated 3.3 V rails or 5 V USB power. Low-power sleep modes between sampling events extend battery life in intermittently powered edge nodes, and the exposed-pad UQFN-48 package grounds well for noisy RF coexistence layouts.
Recommended
Motor Control and Lighting Systems
The megaAVR 0 series' TCA/TCB timers generate complementary PWM outputs for small DC motor drives, fan controllers and LED dimming. On the ATMEGA4809-MUR, Core Independent Peripherals allow a TCB to gate PWM on an ADC or comparator event, implementing cycle-by-cycle current limiting without firmware latency, an important protection feature at 20 MHz deterministic operation. The hardware multiplier accelerates PID compensation loops in C firmware. With 5 V I/O the chip can drive MOSFET gate drivers directly, and the 48-pin package supplies enough GPIO for rotor-position (Hall) inputs, encoder quadrature decoding and fault feedback lines. The exposed pad must be soldered to a ground pour to keep switching noise out of the ADC reference path.
Recommended
Legacy ATmega Design Migration and BOM Continuity
Many OEMs use the ATMEGA4809-MUR as the strategic migration target when classic ATmega parts (ATmega328P, ATmega32A and similar) face allocation or end-of-life pressure. Because the megaAVR 0 family keeps the AVR instruction set and AVR-GCC compatibility, firmware ports are mostly peripheral re-mapping rather than architectural rewrites, and 48 KB Flash leaves headroom for the slightly larger megaAVR 0 core overhead. The 2.5 V to 5 V operating range covers both legacy 5 V and modern 3.3 V rails, easing partial-board redesigns. The FuSa classification also future-proofs products that must add functional-safety documentation. Ordering the MUR (tape and reel) suffix keeps production lines running without tray conversions.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA4809-MUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA4808-MUR | ATMEGA3209-MUR | ATMEGA4809-AUR |
|---|---|---|---|---|
| Package | 48-UQFN (6x6) EP | 48-UQFN (6x6) EP - same | 48-UQFN (6x6) EP - same | 48-TQFP - differs (body style) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 48 KB | 48 KB | 32 KB | 48 KB |
| SRAM | 6 KB | 6 KB | 4 KB | 6 KB |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage | 2.5 V / 3.3 V / 5 V | 2.5 V / 3.3 V / 5 V | 2.5 V / 3.3 V / 5 V | 2.5 V / 3.3 V / 5 V |
| Functional Safety (FuSa) | Yes (megaAVR 0 FuSa) | Yes (megaAVR 0 FuSa) | Yes (megaAVR 0 FuSa) | Yes (megaAVR 0 FuSa) |
| Peripheral Set | Full megaAVR 0 set (48-pin die) | Reduced peripheral variant | Full megaAVR 0 set | Full megaAVR 0 set |
| Packaging | Tape & Reel | Tape & Reel | Tape & Reel | Tape & Reel |
Key Differentiators
- Full 48-pin die connectivity (vs ATMEGA4808-MUR)
- Largest Flash in the 48-pin UQFN family (vs ATMEGA3209-MUR)
- Compact reworkable alternative exists (vs ATMEGA4809-AUR)
Design Notes
The 48-pin UQFN 6x6 mm package has a fine pitch and an exposed pad. Copy the land pattern exactly from the ATmega4808/4809 datasheet (DS40002173B) mechanical drawings, connect the exposed pad to a solid ground pour with an array of vias, and specify a no-clean solder paste with adequate stencil aperture ratio for the center pad. For hand assembly and prototyping, consider ordering the TQFP variant ATMEGA4809-AUR instead, since 0.5 mm-class UQFN pads are difficult to rework.
Place 100 nF ceramic decoupling capacitors at each VDD pin, as close to the package as possible, plus bulk capacitance at the board supply. The part operates from 2.5 V to 5 V; when running from a switching converter, add an RC or ferrite filter ahead of the VDD pins to keep the 10-bit ADC reference clean. Do not float unused die pads on smaller sibling packages - on the 40-pin versions the datasheet requires PB[5:0] and PC[7:6] to be set to INPUT_DISABLE or pull-up enabled.
Programming uses the single-wire UPDI interface on the PA0 pin, not the legacy SPI ISP of older ATmega parts - reserve PA0 as a dedicated UPDI header in your layout, or fuse-configure it as GPIO only after programming is finalized, since disabling UPDI complicates recovery. Also verify peripheral counts against the datasheet if you plan firmware shared with ATmega4808-based boards, because the 4808 is a reduced-peripheral variant of the same die.
For mixed-signal performance, keep the ADC input traces away from high-current PWM or switching nodes and route the analog reference star-connected back to the supply. The Core Independent Peripherals and event system favor short direct routing between peripheral pins (timer outputs, comparator inputs) rather than looping signals through the CPU region of the die.
Compliance Information
RoHS compliant per DigiKey product listing for the megaAVR 0 series. REACH, halogen-free and conflict-minerals status not stated in the provided web data - verify on the Microchip product page.
