LMX2541

• -225 dBc/Hz phase noise PLL return
• Combined RMS noise (100 Hz - 20 MHz)
• 2.1 GHz at 2 milliradians (100 Hz - 20 MHz).
• 3.5 GHz at 3.5 milliradian (100 Hz - 20 MHz).
• Ultra-low noise integrated VCO
• External VCO Scheme (Internal VCO Bypass)
• VCO crossover 1 to 63 (all values)
• Programmable output power
• Up to 104 MHz phase detection frequency
• Integrated low-noise LDO
• Programmable charge pump output
• Partially integrated loop filter
• Digital Frequency Shift Keying (FSK) modulation pins
• Comprehensive reference crystal oscillator circuit
• Hardware and software power outages
• FastLock mode and VCO base skipping reduction
• Analog and digital lockout detection
• 1.6 V Logic Compatibility

illustrate

The LMX2541 is an ultra-low-noise frequency synthesizer that integrates a high-performance delta-sigma decimal N crossover PLL, a fully integrated energy storage circuit VCO, and an optional crossover. The PLL provides an unprecedented standardization of a noise substrate of -225 dBc/Hz, with phase detection rates of up to 104 MHz operating in integer and decimal mode (comparative frequency). The PLL can also be configured to use an external VCO.

The LMX2541 integrates a variety of low-noise, high-precision LDOs and output driver matching networks to provide higher power noise suppression and more stable performance while reducing the number of external components. When combined with a high-quality reference oscillator, LMX2541 produces a very stable, ultra-low noise signal.

The LMX2541 is available in six series of devices with different frequency ranges from 1990 VCO MHz to 4 GHz. Using flexible crossover, LMX2541 can produce low frequencies up to 31.6 MHz. The LMX2541 is a monolithic integrated circuit manufactured on a proprietary BiCMOS process. The device is easily programmed using a three-wire MICROWIRE interface that can operate up to 1.6 volts. The supply voltage ranges from 3.15 to 3.45 volts. The LMX2541 is obtained in a 36-pin 6x6x0.8 mm lead-free lead-free lead frame package (LLP).