| 摘要 |
PURPOSE:To output a detected signal, which is proportional to a conducting current at the time of conduction, without externally attaching a current detecting resistor, by detecting the conducting current based on a voltage between a first electrode and a probe electrode. CONSTITUTION:A probe region 10 has an impurity concentration higher than the impurity concentration of an N<-> type Si substrate 1a and is diffused to a specified diffusing depth between P.type regions 2 or in the N<->type Si substrate 1a at the peripheral part of an element. Contact property is improved by the electrode 10. An electrically connected probe electrode 8 is insulated from a source electrode 7a. A voltage VPS between a probe and a source becomes a voltage, which is exactly proportional to a drain current ID. when the drain current ID is zero, the voltage VPS between the probe and the source caused by the insulating effect of a depletion layer 12 becomes zero, even if a voltage VDS between a drain and the source is not zero. Thus the accurate drain current ID can be detected. |
