Method for detecting soldering failure in IC terminal by tuning type sensor coil

The object of the present invention is to provide a method for detecting the soldering failure in IC terminal by tuning type sensor coil to electrically detect the soldering of an IC terminal at a high speed. A tuning type sensor coil provided with a sensor coil formed by winding a plurality of conductive coils on a cylindrical bobbin formed of a magnetic material core such as ferrite or the like having a diameter conformed to the outer dimension of an IC and a capacitor connected to the output end of the sensor coil, is set on the IC. A means for applying an AC (sine wave, pulse, etc.) signal to a measuring terminal in the IC grounded except the measuring terminal to detect the magnetic field generated by the current carried to a protective diode within the IC by the tuning type sensor coil set on the IC is given to all of the IC terminals. By the detection means of the tuning type sensor coil disposed on the IC, all of the IC terminals are measured. The propriety is judged by the comparison with a preliminarily stored reference value for non-defective IC.