Microchip Technology ATMEGA64RFR2-ZFR

Overview

ATMEGA64RFR2-ZFR from Microchip Technology (formerly Atmel) is an integrated 8-bit AVR microcontroller with a fully embedded 2.4 GHz IEEE 802.15.4/ZigBee transceiver, delivering 64 KB Flash, 2 KB EEPROM, 8 KB SRAM, and 38 programmable I/O lines in a 64-pin QFN package. It operates from 1.8–3.6 V, achieves 16 MIPS at 16 MHz, and supports hardware-assisted MAC, AES encryption, and ultra-low-power Deep Sleep mode (<700 nA). It targets battery-powered wireless sensor nodes and end devices in industrial monitoring and smart home systems.

For engineers reviewing the ATMEGA64RFR2-ZFR datasheet, ATMEGA64RFR2-ZFR pinout, ATMEGA64RFR2-ZFR application, or ATMEGA64RFR2-ZFR equivalent, key selection criteria include its monolithic ZigBee RF+MCU integration, -100 dBm RX sensitivity, 3.5 dBm TX output, hardware-accelerated AES-128, and support for 250 kb/s to 2 Mb/s data rates - all within a single 64-pin QFN footprint optimized for compact, low-power wireless endpoints.

Technical Context

The ATMEGA64RFR2-ZFR integrates an enhanced RISC AVR core with a fully self-contained 2.4 GHz transceiver featuring a fractional-N PLL synthesizer, DSSS modulation, and hardware MAC engine supporting auto-acknowledge, auto-retry, and 32-bit IEEE 802.15.4 symbol counter. Its dual-oscillator system uses a 16 MHz crystal for RF timing and a 32.768 kHz crystal for low-power RTC and symbol timing.

It implements dedicated RF I/O pins (RFP/RFN) with isolated analog grounds (AVSS_RFP/AVSS_RFN), internal voltage regulation (DVDD/AVDD derived from DEVDD/EVDD), and a 10-bit, 330 ks/s ADC with differential input and programmable gain. Power management includes six software-selectable sleep modes, with Deep Sleep enabling sub-µA operation while retaining MAC symbol counter and 32.768 kHz oscillator functionality.

Key Specifications

Pinout & Package

ATMEGA64RFR2-ZFR is housed in a 64-pad QFN (RoHS/Fully Green) package with an exposed metal thermal pad internally connected to AVSS. The pad must be soldered to the PCB for mechanical stability and thermal performance; leaving it unconnected risks delamination.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar wireless microcontroller applications.

Compared with ATMEGA64RFR2-ZFR, the ATMEGA128RFR2-ZUR offers scalable memory headroom within identical hardware constraints, while the CC2652R1F delivers broader protocol flexibility and higher compute capability at the cost of increased software complexity and ecosystem lock-in.

Availability

ATMEGA64RFR2-ZFR is available at Aetrix Electronics and suitable for smart home sensor nodes, industrial wireless monitors, wireless lighting controls, and ZigBee remote controls requiring stable component supply and long-term industrial lifecycle support.

Supply support for ATMEGA64RFR2-ZFR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology acquired Atmel in 2016 and continues to develop, manufacture, and support the AVR microcontroller family with focus on robustness, longevity, and embedded security.

The ATMEGA64RFR2-ZFR belongs to the Atmel RFR2 wireless MCU product line, designed specifically for cost-sensitive, battery-operated IEEE 802.15.4 and ZigBee end-node applications where integration, ultra-low power, and hardware-accelerated security are critical.

FAQ

What is the primary function of the ATMEGA64RFR2-ZFR in a ZigBee network?

The ATMEGA64RFR2-ZFR serves as a full-function ZigBee end-node device, integrating both the 8-bit AVR microcontroller and the 2.4 GHz IEEE 802.15.4 transceiver on a single die. It executes application logic, handles sensor I/O, runs the ZigBee stack (including MAC layer functions accelerated in hardware), and manages RF transmission/reception - eliminating the need for discrete MCU+RF IC designs. This integration reduces BOM cost, board area, and power consumption versus multi-chip solutions.

Does the ATMEGA64RFR2-ZFR support hardware AES encryption?

Yes, the ATMEGA64RFR2-ZFR includes a dedicated hardware AES-128 encryption/decryption engine that operates independently of the CPU. It processes 128-bit blocks in under 1 µs, supports ECB and CTR modes, and interfaces directly with the transceiver's frame buffer - enabling secure over-the-air updates, authenticated device joining, and encrypted payload transmission without consuming CPU cycles or exposing keys in software memory.

What are the required external components for basic ATMEGA64RFR2-ZFR operation?

Basic operation requires a 16 MHz crystal with two 12 pF load capacitors (XTAL1/XTAL2), a 32.768 kHz crystal with 12–25 pF load capacitors (TOSC1/TOSC2), a balun for RF matching (e.g., Johanson 2450FB15L0001), two 22 pF RF coupling capacitors (C1/C2), and bypass capacitors: 1 µF (CB1/CB3) on AVDD/DVDD regulators and 1 µF (CB2/CB4) on DEVDD/EVDD supplies. The exposed thermal pad must be soldered to AVSS.

Can the ATMEGA64RFR2-ZFR operate in Deep Sleep mode while maintaining network timing?

Yes, the ATMEGA64RFR2-ZFR supports Deep Sleep mode with the 32.768 kHz oscillator and 32-bit IEEE 802.15.4 symbol counter remaining active. This allows precise network timing synchronization, beacon interval tracking, and scheduled wake-ups for CSMA-CA channel access - all while drawing less than 700 nA at 25°C. The MAC symbol counter continues incrementing, ensuring accurate timestamping for frame transmission and reception upon wake-up.

How does the ATMEGA64RFR2-ZFR handle RF antenna interfacing?

The ATMEGA64RFR2-ZFR features a differential 100 Ω RF interface (RFP/RFN) with dedicated analog ground returns (AVSS_RFP/AVSS_RFN). It requires an external balun (e.g., 2.4 GHz SMD balun) to convert to a 50 Ω single-ended antenna connection. The device supports antenna diversity via PG1 (DIG1) and PF2 (DIG2) pins, allowing control of external RF switches to select between multiple antennas - improving link reliability in multipath environments without additional RF front-end ICs.