LMX2434 - 5.0 GHz/2.5 GHz PLLatinum Low Power Dual Frequency Synthesizer for RF Personal Communications

Using a proprietary digital-phase, locked-loop technique, the LMX243x devices generate very stable, low-noise control signals for RF and IF voltage controlled oscillators. Both the RF and IF synthesizers include a two-level programmable charge pump. Both the RF and IF PLLs have dedicated fastlock circuitry with integrated time-out counters which require only a single word write to power up or change frequencies.

The LMX243x devices are high-performance frequency synthesizers with integrated dual-modulus prescalers. A 32/33 or a 16/17 prescale ratio can be selected for the 5-GHz LMX2434 RF synthesizer. An 8/9 or a 16/17 prescale ratio can be selected for both the LMX2430 and LMX2433 RF synthesizers. The IF circuitry contains an 8/9 or a 16/17 prescaler.

Serial data is transferred to the devices through a three-wire interface (DATA, LE, CLK). A low voltage logic interface allows direct connection to 1.8-V devices. Supply voltages from 2.25 V to 2.75 V are supported.

• Low Current Consumption
  • LMX2430 (RF/IF): 2.8 mA/ 1.4 mA
  • LMX2433 (RF/IF): 3.2 mA/ 2 mA
  • LMX2434 (RF/IF): 4.6 mA/ 2.4 mA
• 2.25-V to 2.75-V Operation
• Synchronous/Asynchronous Power Down
• Multiple PLL Options:
  • LMX2430 (RF/IF): 3 GHz /0.8 GHz
  • LMX2433 (RF/IF): 3.6 GHz /1.7 GHz
  • LMX2434 (RF/IF): 5 GHz /2.5 GHz
• Programmable Charge-Pump Current Levels
  • RF and IF: 1 or 4 mA
• Fastlock With Integrated Time-Out Counters
• Digital Filtered Lock-Detect Output
• Analog Lock Detect (Push-Pull / Open-Drain)
• 1.8-V MICROWIRE Logic Interface