The LMX2354 is a radio frequency frequency synthesizer manufactured by National Semiconductor. It is fabricated using National’s 0.5 μ ABiC V silicon BiCMOS process and consumes only 7.0 mA of power. The operating frequency range is 2.5 GHz to 550 MHz. The product uses quadruple modulus prescalers and modulo 15 or 16 fractional compensation circuitry in the RF divider to provide a continuous divide ratio of 80 to 32767 in 16/17/20/21 (1.2 GHz–2.5 GHz) fractional mode and 40 to 16383 in 8/9/12/13 (550 MHz–1.2 GHz) fractional mode.
The LMX2354 is a monolithic integrated fractional N/Integer N frequency synthesizer designed for use in local oscillator subsystems for radio transceivers. It utilizes National Semiconductor's 0.5 µm BiCMOS process and features quadruple modulus prescalers along with modulo 15 or 16 fractional compensation circuitry in the RF divider.
The device provides a continuous divide ratio of 80 to 32767 in fractional mode (1.2 GHz-2.5 GHz) and 40 to 16383 in fractional mode (550 MHz—1.2 GHz). It includes an 8/9 prescaler for the IF circuitry and supports a highly flexible 16-level programmable charge pump with output currents ranging from 100 µA to 1.6 mA. The LMX2354 operates with a supply voltage range of 2.7V to 5.5V and is available in 24-pin TSSOP and CSP packages.
| Operating Temperature | -40°C to +85°C |
|---|---|
| Power Supply Voltage | 2.7V to 5.5V |
| Typical Current Consumption (2.5 GHz) | 7.0 mA |
| Typical Current Consumption (Power Down) | 5 µA |
| RF Operating Frequency | 0.5 GHz to 2.5 GHz |
| IF Operating Frequency | 10 MHz to 550 MHz |
| Oscillator Frequency | 2 MHz to 50 MHz |
| Charge Pump Output Current (RF) | 100 µA to 1.6 mA |
| Charge Pump Output Current (IF) | 100 µA or 800 µA |
| Package Types | 24-pin TSSOP and 24-pin CSP |
The supply voltage can range from 2.7V to 5.5V.
The RF operating frequency ranges from 0.5 GHz to 2.5 GHz.
The typical current consumption is 7.0 mA for the 2.5 GHz version and 5 µA in power-down mode.
The device is available in a 24-pin TSSOP surface mount plastic package and a 24-pin CSP.