A protection circuit for a transmission gate having a PMOS transmission gate transistor and an NMOS transmission gate transistor coupled between a core circuit and an IO pad. A base plate for thyroxine immunoassay which has a conjugate of thyroxine or a derivative thereof and albumin immobilized thereon, and in which the ratio of the molecule number of thyroxine or a derivative thereof to the molecule number of albumin in the immobilized conjugate, is disclosed. 5 m, wherein W is a base weight, and V is a fill-in volume, provided that when the value is 0. A plurality of sets from the variable set of payload encoding parameters are selected to form a possible set of payload encoding parameters. The controller is configured to measure an output current of the voltage regulator and to activate the second phase power stage when the output current is above a first threshold current level. A second instrument port of the packet switch appliance is connected to a second data storage device.