Currently have a board with a K61 processor that uses a coin cell battery on the VBAT input to monitor the tamper pins during power down. The battery is 17mAh and is draining overnight. We are also connecting a differential ADC input to monitor battery voltage while powered up. Someone here mentioned hearing of an issue with the differential ADC inputs causing a high drain on the battery. Has anyone heard of this and have any data as to the root cause? Is it a function of the differential inputs? Or is it a particular ADC? If not the ADC, then any other ideas as to why the battery would drain so fast?