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Using DS1077L as External Clock for AD5933 MCLK

Category: Hardware
Product Number: AD5933

I am trying to use DS1077L-40 to generate clock signal from 2MHz to 25KHz (following Table 3 in CN-0217 note) to AD5933 to perform frequency sweep below 5kHz as there are already few examples using DS1077 as the external clock source for AD5933 on this forum. However, as shown in the pictures below (first pic: 13.33MHz; second pic: 4.89kHz), The overshoot of the generated clock signal is very high.

Therefore, I have placed a 500pF shunt capacitor between the output (OUT1) of DS1077L-40 and the MCLK pin of AD5933 to ensure the generated clock is within -0.3V to Vdd+0.3V (according to absolute maximum ratings in datasheet), where my Vdd is 3.3V (3.24V in actual). Below are the pictures of the clock signal after the shunt capacitor was placed (Frequency: 13.33MHz and 4.89kHz):

However, it seems like my AD5933 still cannot detect the external clock as the calibration kept failing. I have even burnt a few AD5933 ICs but I am not sure whether it is because of any overvoltage from the external clock. I have tried to run frequency sweep from 5kHz to 10kHz using the internal oscillator (16.776MHz) and it worked perfectly, so I am pretty sure that the IC functions well. 

Was wondering if anyone could give me some suggestions please? For your reference, below is the schematic of my setup. 

Besides, does anybody know how the required MCLK value with respect to each frequency range in Table 3 in CN-0217 note is calculated please?

Thanks in advance.