Microchip Technology ATMEGA128RFA1-ZF

Overview

ATMEGA128RFA1-ZF from Microchip Technology (formerly Atmel) is a monolithic 8-bit AVR microcontroller integrated with a fully compliant IEEE 802.15.4-2006/2011 and ZigBee-ready 2.4 GHz transceiver. It delivers 16 MIPS at 16 MHz, features 128 KB Flash, 4 KB EEPROM, 16 KB SRAM, and operates from 1.8 V to 3.6 V across –40°C to +125°C. It enables self-contained wireless sensor nodes in industrial automation and smart metering.

For engineers reviewing the ATMEGA128RFA1-ZF datasheet, ATMEGA128RFA1-ZF pinout, ATMEGA128RFA1-ZF application, or ATMEGA128RFA1-ZF equivalent, key selection criteria include its integrated MAC hardware acceleration, AES-128 security engine, ultra-low deep-sleep current (<250 nA), and dual-crystal support (16 MHz RF + 32.768 kHz RTC).

Technical Context

The ATMEGA128RFA1-ZF combines an enhanced RISC CPU with a fractional-N synthesizer-based 2.4 GHz transceiver supporting DSSS modulation, hardware CRC-16, auto-acknowledge, and 32-bit IEEE 802.15.4 symbol counter. Its radio subsystem includes dedicated differential RF I/O (RFP/RFN), on-chip voltage regulators (DVDD/AVDD), and antenna diversity control via PG1/PG2.

It implements six software-selectable power modes - including Deep Sleep (<250 nA), Power-down, and ADC Noise Reduction - with independent clock domains for the AVR core (16 MHz) and asynchronous timer (32.768 kHz). The transceiver supports data rates of 250 kb/s, 500 kb/s, 1 Mb/s, and 2 Mb/s with –100 dBm RX sensitivity and up to +3.5 dBm TX output power.

Key Specifications

Pinout & Package

ATMEGA128RFA1-ZF uses a 64-pad QFN package (RoHS/Fully Green) with exposed metal paddle internally connected to AVSS for mechanical stability and thermal dissipation. The center pad must be soldered to PCB ground plane per datasheet recommendation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit wireless microcontroller applications.

Compared with ATMEGA128RFA1-ZF, ATMEGA256RFR2-ZUR offers more Flash but omits critical 32.768 kHz timing infrastructure for ZigBee MAC, while CC2652R1FIPNR provides broader protocol support at the cost of ecosystem discontinuity and higher power in active modes.

Availability

ATMEGA128RFA1-ZF is available at Aetrix Electronics and suitable for smart metering, industrial sensor networks, ZigBee router nodes, and WirelessHART field devices requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for ATMEGA128RFA1-ZF 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 maintains full support for the AVR wireless portfolio. The company specializes in microcontrollers, analog, FPGA, and connectivity solutions for industrial, automotive, and IoT markets.

The ATMEGA128RFA1-ZF belongs to Atmel's legacy AVR Wireless family, designed specifically for ultra-low-power, standards-compliant 2.4 GHz mesh networking in resource-constrained embedded systems.

FAQ

What is the maximum transmit output power of the ATMEGA128RFA1-ZF transceiver?

The ATMEGA128RFA1-ZF transceiver achieves a maximum TX output power of +3.5 dBm. This value is measured under specified conditions (3.0 V supply, 25°C ambient) and enables robust link budgets in ZigBee and IEEE 802.15.4 deployments. The ATMEGA128RFA1-ZF supports programmable power levels down to –25 dBm in 1 dB steps, allowing optimization for range versus battery life.

Does the ATMEGA128RFA1-ZF support hardware AES encryption?

Yes, the ATMEGA128RFA1-ZF integrates a dedicated AES-128 encryption engine and true random number generator (TRNG) compliant with FIPS 140-2 requirements. These hardware accelerators operate independently of the AVR core, enabling secure key exchange and payload encryption without CPU intervention. The ATMEGA128RFA1-ZF uses this capability to meet ZigBee and WirelessHART security mandates.

What crystal frequencies are required for full functionality of the ATMEGA128RFA1-ZF?

The ATMEGA128RFA1-ZF requires two crystals: a 16 MHz crystal on XTAL1/XTAL2 for RF carrier synthesis and a 32.768 kHz crystal on TOSC1/TOSC2 for IEEE 802.15.4 symbol timing and RTC functions. Omitting the 32.768 kHz crystal disables hardware MAC symbol counter and low-power timekeeping, limiting compliance with ZigBee timing requirements. The ATMEGA128RFA1-ZF does not support internal RC oscillators for these critical timing domains.

How many I/O pins does the ATMEGA128RFA1-ZF provide, and which ports are implemented?

The ATMEGA128RFA1-ZF provides 38 programmable I/O lines across Ports B, D, E, F, G, and partial Port P. Ports A and C are omitted entirely - their registers exist but have no physical pin mapping. Port G is 6-bit (PG0–PG5), with reduced drive strength on PG3/PG4. The ATMEGA128RFA1-ZF pinout excludes PA0–PA7 and PC0–PC7, simplifying layout while retaining full peripheral functionality on remaining ports.

What power modes does the ATMEGA128RFA1-ZF support, and what is the lowest achievable current draw?

The ATMEGA128RFA1-ZF supports six software-selectable power modes: Idle, Power-down, Power-save, ADC Noise Reduction, Standby, and Extended Standby. In Deep Sleep mode - activated via SMCR register - total supply current drops below 250 nA at 25°C, with only the watchdog timer, MAC symbol counter, and 32.768 kHz oscillator active. The ATMEGA128RFA1-ZF achieves this ultra-low leakage through aggressive digital block gating and optimized process technology.