Question
Could you tell me the differential input impedance of AD9600? I can not find this parameter in the datasheet.Refer to figure 47 on the datasheet (see attachment), could you please let me know the ratio of transformer, is it 1:1?Is the value suggested for RC in Table 10 under the condition of 1:1.
Answer
The input impedance of the AD9600 is frequency dependent and is specified by our S-parameter data(I have attached the data for the AD9640 and AD9627 which is identical to the AD9600).AN-935 discussed a method of using the S-parameter data to match the input impedance.In figure 47 the ratio of the transformer is indeed 1:1 and the RC value suggested in table 10 assumes a 1:1 transformer.