Texas Instruments LMX2594宽带PLLatinum射频合成器

Texas Instruments LMX2594宽带PLLatinum™射频合成器集成有VCO，输出频率范围为10MHz至15GHz，且无需内部倍频器。得益于这一特性，无需使用次谐波滤波器。该款高性能PLL具有–236dBc/Hz的品质因数和高相位检波器频率，可实现极低的带内噪声和集成抖动。高速N分频器没有预分频，因此显著降低了杂散的振幅并减少了数量。另外还设有一个可编程输入乘法器，可减轻整数边界杂散。LMX2594允许用户同步多个器件的输出，另外还支持在输入和输出之间需要确定性延迟的应用。频率斜坡发生器可以在自动斜坡发生选项或手动选项中最多合成两段斜坡，以实现最大的灵活性。利用快速校准算法，可将频率更改为快于20µs。LMX2594增加了对生成或重复SYSREF（符合JESD204B标准）的支持，因此非常适合用于面向高速数据转换器的低噪声时钟源。该配置中具有精细的延迟调整（9ps分辨率），以应对电路板走线的延迟差异。

The LMX2594 allows users to synchronize multiple devices' output and enables applications requiring a deterministic delay between input and output. A frequency ramp generator can synthesize up to 2 segments of a ramp in an automatic ramp generation option or a manual option for maximum flexibility. The fast calibration algorithm allows changing frequencies faster than 20µs. The Texas Instruments LMX2594 supports generating or repeating SYSREF (compliant with JESD204B standard), making it an ideal low-noise clock source for high-speed data converters. Fine delay adjustment (9ps resolution) is provided in this configuration to account for delay differences of board traces.

特性

10MHz to 15GHz output frequency
-110dBc/Hz phase noise at 100kHz offset with 15GHz carrier
45fs rms Jitter at 7.5GHz (100Hz to 100MHz)
Programmable output power up to 7dBm at 15GHz
PLL key specifications
- Figure of merit: -236dBc/Hz
- Normalized 1/f noise: -129dBc/Hz
- High phase detector frequency
  - 400MHz integer mode
  - 300MHz fractional mode
- 32-bit fractional-N divider