AC coupling modules for bias ladders
US11870431B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 2022 |
| Grant date | Jan 9, 2024 |
| Priority date | — |
| Expiry date | Sep 16, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/0054
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A positive-logic FET switch stack that does not require a negative bias voltage, exhibits high isolation and low insertion/mismatch loss, and may withstand high RF voltages. Embodiments include a FET stack comprising series-coupled positive-logic FETs (i.e., FETs not requiring a negative voltage supply to turn OFF), series-coupled on at least one end by an “end-cap” FET of a type that turns OFF when its VGS is zero volts. The one or more end-cap FETs provide a selectable capacitive DC blocking function or a resistive signal path. Embodiments include a stack of FETs of only the zero VGS type, or a mix of positive-logic and zero VGS type FETs with end-cap FETs of the zero VGS type. Some embodiments withstand high RF voltages by including combinations of series or parallel coupled resistor ladders for the FET gate resistors, drain-source resistors, body charge control resistors, and one or more AC coupling modules.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.