摘要 |
An electronic SPDT switch (1) has, a series FET (9) in a first circuit arm (4) between a common port (2) and a first port (3), a shunt FET (10) in a second circuit arm (6) between the common port (2) and a second port (5), the shunt FET (10) being isolated 90 degrees or +E,fra 1/4+EE wavelength from the common port (2), a source applying pull-up voltage to sources of respective FETs (9, 10) and to the common port (2), to provide a connection of the common port (2) with said second port (5), a source applying a first control voltage of opposite logic state to said gates, and the FETs (9, 10) being depletion mode FETs that conduct at a zero sum of said bias voltage and said control voltage, and that conduct when DC power is interrupted, to provide a connection of the common port (2) with the first port (3).
|