LMX2485Q-Q1是TI公司的一款无产品，LMX2485Q-Q1是用于射频个人通信的汽车类 Δ-Σ 低功率双路 PLL，本页介绍了LMX2485Q-Q1的产品说明、应用、特性等，并给出了与LMX2485Q-Q1相关的TI元器件型号供参考。
LMX2485Q-Q1 - 用于射频个人通信的汽车类 Δ-Σ 低功率双路 PLL - 无 - RFPPL与合成器 - TI公司（Texas Instruments，德州仪器）
The LMX2485EQ is a low power, high performance delta-sigma fractional-N PLL with an auxiliary integer-N PLL. The device is fabricated using TI’s advanced process.
With delta-sigma architecture, fractional spurs at lower offset frequencies are pushed to higher frequencies outside the loop bandwidth. The ability to push close in spur and phase noise energy to higher frequencies is a direct function of the modulator order. Unlike analog compensation, the digital feedback technique used in the LMX2485EQ is highly resistant to changes in temperature and variations in wafer processing. The LMX2485EQ delta-sigma modulator is programmable up to fourth order, which allows the designer to select the optimum modulator order to fit the phase noise, spur, and lock time requirements of the system.
Serial data for programming the LMX2485EQ is transferred via a three line high speed (20 MHz) MICROWIRE interface. The LMX2485EQ offers fine frequency resolution, low spurs, fast programming speed, and a single word write to change the frequency. This makes it ideal for direct digital modulation applications, where the N counter is directly modulated with information. The LMX2485EQ is available in a 24 lead 4.0 × 4.0 × 0.8 mm WQFN package.
- Quadruple Modulus Prescalers for Lower Divide Ratios
- RF PLL: 8/9/12/13 or 16/17/20/21
- IF PLL: 8/9 or 16/17
- Advanced Delta Sigma Fractional Compensation
- 12 bit or 22 bit Selectable Fractional Modulus
- Up to 4th Order Programmable Delta-sigma Modulator
- Features for Improved Lock Times and Programming
- Fastlock / Cycle Slip Reduction
- Integrated Time-out Counter
- Single Word Write to Change Frequencies with Fastlock
- Wide Operating Range
- LMX2485EQ RF PLL: 50 MHz to 3.0 GHz
- Useful Features
- Digital Lock Detect Output
- Hardware and Software Power-down Control
- On-chip Crystal Reference Frequency Doubler.
- RF Phase Comparison Frequency up to 50 MHz
- 2.5 to 3.6 Volt Operation with ICC = 5.0 mA at 3.0 V
- LMX2485Q is AEC-Q100 Grade 2 Qualified and is Manufactured on an Automotive Grade Flow
