LMX2316TMX/NOPB

Clock Generators, PLLs, Frequency Synthesizers Overview

The LMX2316TMX/NOPB is an obsolete monolithic PLLatinum low-power frequency synthesizer designed for RF personal communications. It operates within a supply voltage range of 2.3V to 5.5V and features ultra-low current consumption, drawing approximately 2.5mA at 3V in normal operation. The device incorporates a 32/33 dual modulus prescaler and supports programmable or logical power-down modes with typical standby current of 1μA. It utilizes a MICROWIRE serial interface for configuration and includes selectable charge pump tri-state and FastLock modes. The component is housed in a 16-pin TSSOP surface-mount package.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated digital phase-locked loop architecture utilizing a 32/33 dual modulus prescaler for stable local oscillator signal generation.
• Programmable power-down functionality allowing selection between synchronous and asynchronous modes to minimize active DC current paths.
• FastLock mode capability enabling dynamic adjustment of PLL loop bandwidth to achieve rapid frequency transitions while maintaining phase noise performance.
• Digital lock detect output providing status indication when the VCO frequency achieves lock relative to the reference oscillator.

Clock Generators, PLLs, Frequency Synthesizers Applications

• Portable wireless communications systems including PCS and PCN handsets
• Cordless telephone applications requiring low power consumption
• Wireless local area networks (WLANs) operating in ISM bands
• Cable TV tuners (CATV) requiring stable frequency synthesis

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

This component is officially classified as obsolete by Texas Instruments. Verify availability through authorized distributors for remaining stock or consider alternative replacement parts. Ensure compatibility with existing design constraints before procurement.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this component only if legacy support for the specific 1.2GHz RF input range and 32/33 prescaler topology is required. Evaluate the 16-pin TSSOP footprint and MICROWIRE interface requirements against current system designs.

Clock Generators, PLLs, Frequency Synthesizers Part Context

The LMX2316 belongs to the LMX2306/16/26 family of PLLatinum synthesizers. While sharing identical packaging and control interfaces, the LMX2316 is distinguished by its 1.2GHz maximum RF input frequency, whereas the LMX2306 supports up to 550MHz and the LMX2326 supports up to 2.8GHz.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

As an obsolete part, direct replacements are not guaranteed. Consult Texas Instruments documentation for updated frequency synthesizer families that offer similar low-power specifications and MICROWIRE compatibility.

Clock Generators, PLLs, Frequency Synthesizers FAQ

What is the function of the FLo pin?

The FLo pin serves as a FastLock output. When FastLock is enabled, it indicates the state of the high-gain mode; otherwise, it can be configured as a general-purpose output controlled by the F9 bit.

How does the device handle power-down operations?

The device supports both synchronous and asynchronous power-down modes via the MICROWIRE interface. Synchronous mode prevents unwanted frequency jumps by gating the powerdown function with the charge pump, while asynchronous mode powers down immediately upon latching the control bit.

What is the purpose of the FastLock Timeout Counter?

The FastLock Timeout Counter allows the device to automatically exit the high-gain FastLock mode after a programmable number of phase detector reference cycles, transitioning seamlessly back to normal low-current operation without requiring a MICROWIRE command.