LMX2542LQ2121/NOPB

Clock Generators, PLLs, Frequency Synthesizers Overview

The LMX2542LQ2121/NOPB is an obsolete PLLatinum Cellular and GPS Frequency Synthesizer System with an integrated VCO, manufactured by Texas Instruments. It operates from a 2.7V to 3.3V supply with typical current consumption of 22 mA at 2.8V. The device features a Fractional-N RF PLL based on an 11-bit ΔΣ modulator for low spurious performance and an Integer-N IF PLL with a programmable charge pump. The RF synthesizer system operates between 2087.73 MHz and 2155.14 MHz, while the default IF frequency is 367.20 MHz. It supports reference frequencies of 19.20 MHz or 19.68 MHz via a MICROWIRE interface and is housed in a 28-pin WQFN package.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated RF VCO and loop filter designed for cellular-CDMA and GPS applications
• Fractional-N RF PLL architecture utilizing an 11-bit Delta Sigma modulator
• Integer-N IF synthesizer system with four-level programmable charge pump currents
• Digital filtered lock detect output for monitoring RF synthesizer status

Clock Generators, PLLs, Frequency Synthesizers Applications

• Cellular-CDMA 1xRTT mobile handsets with GPS capabilities
• IS-95 mobile data systems with GPS integration
• Wireless communication devices requiring stable local oscillator signals

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

This component is officially marked as obsolete by Texas Instruments. Verify availability through authorized distributors for remaining stock or consider replacement strategies. Confirm that the specific ordering suffix matches the required packing quantity and package variant before procurement.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this part only if legacy support for CDMA 1xRTT and IS-95 standards is required. Ensure the design accommodates the need for external /2 or /1.5 divider circuits for specific LO configurations. Verify compatibility with the 28-pin WQFN footprint and MICROWIRE serial interface requirements.

Clock Generators, PLLs, Frequency Synthesizers Part Context

The LMX2542LQ2121/NOPB belongs to the LMX2542 family of PLLatinum frequency synthesizers. It is specifically optimized for wireless communications devices operating in the cellular bands. The 'LQ' suffix indicates the leadless leadframe WQFN package, and '2121' denotes the specific RF center frequency configuration.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. As the device is obsolete, consult Texas Instruments for current generation alternatives suitable for cellular and GPS frequency synthesis.