Amplifier protection circuit
US5300897A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 6, 1992 |
| Grant date | Apr 5, 1994 |
| Priority date | — |
| Expiry date | Nov 6, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q1/50
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The protection circuit includes a micro strip line whose length is equal to a fourth of the wavelength of an amplification signal frequency on a board and whose one side is connected to the input side of a low noise amplifier, a diode whose one side is connected to the other side of the micro strip line and whose other side is grounded, and a capacitor which is connected to the point where the micro strip line is connected to the diode and whose impedance is sufficiently small at the amplification signal frequency. In this configuration, the diode has virtually no effect to the amplification signal component because the impedance of the protection circuit for the amplification signal frequency viewed from the contact point becomes sufficiently high. In addition, for static electricity charged on the antenna connected to the input terminal, the diode is virtually connected directly to the input side of the low noise amplifier because the micro strip line is almost zero in resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.