| 摘要 |
PURPOSE:To improve a gain while suppressing astability by connecting emitter capacitors dedicating themselves to an operating frequency band and low-frequency band in parallel between the emitter of a transistor and the ground. CONSTITUTION:Between the emitter pattern of transistor Q1 connecting to input- output matching networks M1 and M2 and the ground, 1st capacitor CE1 with a serial resonance frequency at the low terminal of the in-use frequency band of an amplifier and 2nd capacitor CE2 with the serial resonance frequency at a frequency much lower than the in-use frequency are connected in parallel. To a base bias circuit, low-pass filter 60 is connected which consists of choke coil L1, capacitors CB1 and CB2, and resistance RB. As a result, a sufficient gain can be obtained and astability due to a parallel connection between capacitors can also be suppressed by low-pass filter 60, so that its stability will improve. |
