DEVICE INTRODUCED INTO SUBJECT

摘要

A protective circuit (26c) detects the voltage at point A on a power supply path from a battery (29) to a circuit (30) executing a function in a capsule. When the voltage at point A drops below a preset threshold (predetermined intermediate potential), a switch element (26a) is switched to connect the battery (29) with a resistor load (26b), and the supply of drive power to the circuit (30) is interrupted. At the same time, the resistor load (26b), can be supplied with power and power stored in the battery (29) is used up through the resistor load (26b), thus preventing erroneous operation of the circuit in an intermediate potential state.