Microchip Technology AT86RF211SAH-R

Overview

AT86RF211SAH-R from Microchip Technology (formerly Atmel) is a monolithic FSK transceiver IC for ISM-band wireless systems, operating from 400 to 950 MHz with up to 100 kbps data rate, +16 dBm output power at 433 MHz, integrated PLL/VCO, and 3-wire serial interface. It serves as a microcontroller RF peripheral in battery-powered telemetry, remote control, and AMR applications.

For engineers reviewing the AT86RF211SAH-R datasheet, AT86RF211SAH-R pinout, AT86RF211SAH-R application, or AT86RF211SAH-R equivalent, key selection considerations include its shrink-process power reduction (20% lower current vs. AT86RF211), wake-up receiver capability (3 µA typ.), DIGOUT pin multifunctionality (XTO clock, carrier detect, PLL lock flag), and software-activated ADDFEAT mode enabling new features without hardware change.

Technical Context

The AT86RF211SAH-R implements a dual-IF superheterodyne receiver architecture with programmable IF1 (10.7 MHz or 21.4 MHz) and fixed IF2 (455 kHz), supporting crystal-based reference oscillators at 10.245 MHz, 20.5 MHz, or 20.945 MHz. Its synthesizer delivers 200 Hz channel spacing across 400–480 MHz and 800–950 MHz bands using an on-chip charge-pump PLL (225 µA typical).

Transmit and receive paths share a single SPST RF switch with 4 dB insertion loss and 30 dB reverse isolation; the LNA offers 17 dB gain (13 dB min) and 9 dB NF at 900 MHz. The FSK demodulator uses analog oscillator-based discrimination with four selectable discriminator bandwidths (±25 to ±125 kHz) and supports transparent asynchronous/synchronous modes via built-in clock recovery.

Key Specifications

Pinout & Package

AT86RF211SAH-R is housed in a 48-pin QFN package (7 mm × 7 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are validated per Rev. 5348A–WIRE–05/05 datasheet and confirmed on Microchip's official product page.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FSK transceiver applications.

Compared with Si4432-B1B-FMR and CC1101RGPR, the AT86RF211SAH-R uniquely balances integration (on-chip PLL/VCO, DIGOUT clocking, wake-up timer), ultra-low sleep current (3 µA), and seamless AT86RF211 migration path-making it optimal for battery-constrained, standards-compliant ISM systems requiring field-upgradable feature sets.

Availability

AT86RF211SAH-R is available at Aetrix Electronics and suitable for smart metering, industrial remote control, wireless sensor networks, and consumer telemetry devices requiring stable component supply and long-term lifecycle assurance.

Supply support for AT86RF211SAH-R 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 technical and manufacturing responsibility for the AT86RF211SAH-R family. Microchip is a global leader in microcontrollers, analog, and connectivity solutions with ISO 9001-certified fabrication and test facilities.

The AT86RF211SAH-R belongs to Microchip's legacy Atmel RF transceiver product line, designed specifically for low-power, license-free ISM band communication in battery-operated telemetry, remote control, and automatic meter reading systems.

FAQ

What is the primary functional difference between AT86RF211SAH-R and the original AT86RF211?

The AT86RF211SAH-R is a shrink-version process improvement delivering 20% lower current consumption while maintaining full pin, register, and software compatibility with AT86RF211 at power-on reset. New features-including DIGOUT multifunctionality, faster RSSI (1.5 µs ADC clock), low-current XTALRUN mode (150 µA), and 20.5 MHz crystal support-are activated via the ADDFEAT bit (CTRL1[0]). This enables seamless migration for existing AT86RF211 designs while adding capabilities for new implementations without hardware revision.

Does AT86RF211SAH-R support wake-up functionality without external components?

Yes, AT86RF211SAH-R integrates a fully autonomous wake-up receiver that operates in stand-alone mode. When configured, it periodically scans for a predefined header+address sequence using internal timing-drawing only 3 µA typical. Upon detection, it stores up to 32 bits of payload and asserts the WAKEUP pin to interrupt the host MCU. No external timers, comparators, or logic are required, making AT86RF211SAH-R ideal for ultra-low-power sensor nodes where battery life exceeds five years.

Can AT86RF211SAH-R generate a clock signal for its companion microcontroller?

Yes, AT86RF211SAH-R provides a calibrated clock output on the DIGOUT pin (Pin 17) in RF211S mode (ADDFEAT = 1). Supported frequencies include 10.245 MHz, 20.5 MHz, and 20.945 MHz-each derived from the internal crystal oscillator and programmable via DTR[20:14] divider bits. This eliminates the need for a separate crystal on the MCU, reducing BOM cost and board area while ensuring precise clock synchronization between radio and controller.

What are the supported IF configurations and why do they matter for AT86RF211SAH-R design?

AT86RF211SAH-R supports two IF1 configurations: 10.7 MHz (with 10.245 or 20.5 MHz crystal) and 21.4 MHz (with 20.945 MHz crystal). The 10.7 MHz option leverages low-cost, multivendor ceramic filters; the 21.4 MHz option improves image rejection and selectivity using quartz filters. Selection directly impacts external component count, cost, and RF performance-e.g., 21.4 MHz enables front-end ceramic filtering instead of SAW, simplifying matching networks while meeting EN 300 220 spectral mask requirements.

How does the data slicer in AT86RF211SAH-R handle DC-biased signals like NRZ?

AT86RF211SAH-R offers three data slicer modes. In "Internal" mode, a DAC-generated threshold (tunable via DTR[5:2]) enables absolute slicing-allowing infinite transmission of '0' or '1' bits without transitions. In "Charge and Hold" mode, the threshold is stored on the external SKFILT capacitor after initial charging, preserving stability during long constant-bit sequences. Both modes eliminate Manchester encoding requirements, simplifying protocol stack implementation for UART-based telemetry in AT86RF211SAH-R systems.