Question about ADRV9002 TX/RX PFIR filter delay

Question

We know that ADRV9002 TX/RX PFIR filter will have maximum 128 taps. 
 And when you upload the X/RX PFIR filter coefficients, when you tap number is less than 128, ADRV9002 will automatically append 0s to achieve 128 taps. 
 And we know that the PFIR delay is (number of taps)/(2* sample rate). 
 So my questions is that if I load two different PFIR filter coefficients. One is 32-tap and the other is 48-tap. 
 Does my first PFIR delay will be (16/sample rate) and my second PFIR delay will be 24/sample rate ? 
 Or actually both PFIRs delay will be (64/sample rate) since ADRV9002 will automatically append 0s to achieve 128 taps? 
 Thanks a lot!

M_Bugajski · Accepted Answer

Hi Aaron, 
 Zero-padding the PFIR coefficients is not done automatically by the ADRV9002. It is instead done at the API level in the FPGA/BBIC. Therefore, since both cases are still loading a 128-tap PFIR, you should expect to see the same delay. 
 Kind Regards, Michał)

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Question about ADRV9002 TX/RX PFIR filter delay