I want to evaluate an analog part with an ADS6148EVM. (The Analog device is part of measurement system, with uses the ADS6148, too!). I connect the ADS6148EVM with a TSW1200 for the communication. The measurement clock (50MHz) is generated by an AD5920-3. (I’m using the AD5920 in the system, too!). For the best EMC, all parts are shielded!
I want to measure and evaluate the noise generation of the analog part, but I measure with the ADS1248 already a bit noise of 3 Bit, if the SMA-Socket is open and 6 Bit noise, if the SMA-Socket is shorted to Ground. A 50Ohm termination causes a 6 Bit Noise, too!
I can't find any information about the bit noise performance of the ADS6148EVM. My 6Bit seems a lot. Is this normal? Are they some information, about the handling and measurement with the ADS6148EVM?
Noise Signal with open SMA-Socket
Noise Signal, SMA Socket shorted to Ground