LMX2502LQ1635

Overview

The LMX2502LQ1635/NOPB is a PLLatinum frequency synthesizer system with an integrated VCO, manufactured by Texas Instruments following the acquisition of National Semiconductor. It operates within an output frequency range of 1.61962 GHz to 1.64962 GHz. The device supports supply voltages between 2.7 V and 3.3 V, drawing a typical operating current of 17 mA. It is housed in a 28-pin WQFN package and is qualified under AEC-Q100 standards for automotive applications, functioning reliably across temperatures from -30°C to +85°C.

Feature Summary

• Integrates a phase-locked loop (PLL) and voltage-controlled oscillator (VCO) into a single system solution.
• Designed specifically for CDMA and PCS wireless communication applications.
• Complies with AEC-Q100 qualification standards for automotive electronic components.

Applications

• CDMA mobile communication systems
• PCS (Personal Communications Service) transceivers
• Automotive electronics requiring RF frequency synthesis

Procurement Notes

Verify that the component is sourced as the LMX2502LQ1635/NOPB variant, which indicates lead-free construction and compliance with RoHS directives. Confirm the manufacturer origin is Texas Instruments, as National Semiconductor was acquired. Ensure the part meets AEC-Q100 automotive qualification requirements if used in vehicle systems. Check datasheet specifications for the specific 1.635 GHz center frequency configuration to match design needs.

Selection Notes

Select this component when a fixed-frequency synthesizer solution is required for CDMA or PCS bands around 1.635 GHz. The integrated VCO simplifies design by reducing external component count compared to discrete solutions. Consider the 28-WQFN package size for space-constrained PCB layouts. Verify that the 17 mA current consumption aligns with power budget constraints for portable or battery-operated devices.

Part Context

This part belongs to the LMX2502/LMX2512 PLLatinum family, originally developed by National Semiconductor and now produced by Texas Instruments. The '1635' suffix denotes a factory-programmed center frequency of approximately 1.635 GHz. The '/NOPB' suffix signifies a non-pb-free (lead-free) product compliant with environmental regulations. It serves as a specialized RF IC for cellular infrastructure and handsets.

Replacement Considerations

The obsolete LMX2522LQ1635 may be replaced by the LMX2522LQ1635/NOPB. For direct functional equivalents within the same family, consult the official Texas Instruments substitution guide for the LMX2502 series. Ensure any substitute maintains the 28-WQFN footprint and AEC-Q100 qualification if automotive use is intended.