SAR ADC analog input circuit for the (LTC2366)

Question

Hi everyone , i search for the SAR ADC analog input circuit for the LTC2366 (ADC) to simulate on the LT spice. 
 Thanks You

ghoover · Accepted Answer

If you look at Figure 3a of the LTC2308 data sheet that will give you a rough idea of the schematic. The bottom of capacitor Cin may actually be tied to Vref/2. For the values of Ron and Cin use 20pF and 159ohms. 20pF is from Cin and 159ohms is based on the 50MHz -3dB BW.