| 摘要 |
PURPOSE: To realize a small-sized circuit board having large density and to meet high frequency and high speed by crossing adjacent folding lines, specifying the angle therebetween and setting the distance between the vertexes of the lines of the adjacent folding lines to a line width or more. CONSTITUTION: A thin film made of copper extended in a folding line state is formed on a circuit board. When the crossing angle of the adjacent lines of the film is 2θ, the angle is 7 to 60 deg.. Further, the distance P between the vertexes of the adjacent lines is a line width (d) or more. Since the leads are not disposed in parallel different from a spiral coil, a capacitance between the lines is scarcely generated, the resonance frequency and inductance are high and the stray capacitance is low. Thus, a small-sized circuit board having high density can be realized, and the coil can meet the need for high frequency and high speed. |
