SI4311-B21-GMR

RF Receivers Overview

The SI4311-B21-GMR is a fully integrated FSK CMOS RF receiver designed for unlicensed UHF bands. It operates at frequencies of 315 MHz and 433.92 MHz. The device supports a supply voltage range from 2.7 V to 3.6 V with an operating current of 20 mA. It features a QFN-20 package suitable for surface mount installation. The component functions within a temperature range of -40°C to +85°C.

RF Receivers Feature Summary

• Fully integrated FSK CMOS architecture for sub-GHz reception
• Operates in unlicensed 315 MHz and 433.92 MHz UHF bands
• Low power consumption with 20 mA operating current
• Wide operating voltage range supporting 2.7 V to 3.6 V

RF Receivers Applications

• Wireless sensor networks
• Remote keyless entry systems
• Alarm system receivers
• Industrial telemetry applications

RF Receivers Procurement Notes

This component is officially classified as obsolete and no longer manufactured by Silicon Labs. Verification of availability should focus on surplus distributors or secondary market sources rather than direct manufacturer channels. Buyers must confirm the authenticity of stock through authorized surplus dealers and request recent lot traceability documentation to ensure component integrity prior to procurement.

RF Receivers Selection Notes

Engineers should evaluate the SI4311-B21-GMR primarily for legacy design maintenance or replacement strategies where specific 315/433.92 MHz FSK performance is required. Due to its end-of-life status, new designs should consider alternative active components from the same family or newer generations that offer similar frequency coverage and modulation capabilities without supply chain risks associated with discontinued parts.

RF Receivers Part Context

The SI4311-B21-GMR belongs to the Si4311 series of wireless transceivers produced by Silicon Labs. This series targets cost-sensitive, low-power applications requiring reliable short-range communication. The B21 suffix typically denotes specific frequency band configurations and packaging variants within the broader product line, distinguishing it from other regional or functional iterations.

RF Receivers Replacement Considerations

Public confirmed substitute part numbers include SI4355-C2A-GMR. Designers should verify pin compatibility and register-level software migration requirements when transitioning from this obsolete receiver to the suggested alternative.