| 摘要 |
PROBLEM TO BE SOLVED: To constitute a compact and low-loss isolator (nonreciprocal circuit element) having a low input impedance. SOLUTION: A center conductor 2, a magnetic assembly 3 of ferrite 1, a permanent magnet 6 and a spacer 7 are disposed in a case 4, together with series and parallel capacitors C0 , C1 connected to the center conductor 2a for input port, a parallel capacitor C2 connected to the center conductor 2b for output port, a parallel capacitor C3 connected to the center conductor 2c at a termination end, and a resistor R being a termination. The input port center conductor 2a is made broader than the other center conductors 2b, 2c. This lowers the characteristic impedance of the input port center conductor 2a and hence the inductance L of a lumped constant circuit element assumed therefrom, thereby broadening the operating frequency band, when it is made to match with C0 and C1 , to low impedance. Moreover, its equivalent series resistance value is reduced, to make the loss small.
|
