Part Number: ADS1247 Hello We are using an ADC1247 to measure temperatures with a PT100 4-wire sensor. To protect the circuitry we have added two anti-serial protection diodes (PESD3V3UB) on each of the 4 sensor output pins. The circuit around the ADS1247 is placed on a galvanically isolated area connected to the controller side with a ISOW7841 . The isolation barrier is protected by 6 transducer diodes P4SMA540 in series. During impulse voltage test according to the IEC standard we discovered that the ADC was damaged. After changing the ADC the channel works again. How can we improve the protection of our circuitry so the IEC 60255-27 type test can be performed without damaging any circuit parts? Best regards Mikael Badenius ABB Sweden
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