ZHCSEK3G December 2015 – August 2022 LMX2592
PRODUCTION DATA
请参考 PDF 数据表获取器件具体的封装图。
Follow these recommended settings to design for wide loop bandwidth and extract FOM and flicker noise. The flat model is the PLL noise floor modeled by: PLL_flat = PLL_FOM + 20 × log(Fvco/Fpd) + 10 × log(Fpd / 1 Hz). The flicker noise (also known as 1/f noise) which changes by –10dB / decade, is modeled by: PLL_flicker (offset) = PLL_flicker_Norm + 20 × log(Fvco / 1 GHz) – 10 × log(offset / 10k Hz). The cumulative model is the addition of both components: PLL_Noise = 10*log(10PLL_Flat / 10 + 10PLL_flicker / 10). This is adjusted to fit the measured data to extract the PLL_FOM and PLL_flicker_Norm spec numbers.
PARAMETER | VALUE |
---|---|
PFD (MHz) | 200 |
Charge pump (mA) | 12 |
VCO frequency (MHz) | 5400 |
Loop bandwidth (kHz) | 2000 |
Phase margin (degrees) | 30 |
Gamma | 1.4 |
Loop filter (2nd order) | |
C1 (nF) | 0.01 |
C2 (nF) | 0.022 |
R2 (kΩ) | 4.7 |