RF DC-Feeder

A DC feeder is essentially a broadband bias tee without the capacitor. One reason for using this is when an AC-coupled device (e.g. an amplifier) already has a capacitor on its input, which is capable of separating the device from the bias voltage. The slightly lower insertion loss of the DC feeder makes this an attractive alternative to a wideband bias tee.

A more specialized application is to measure the current flowing into a device in conjunction with a bias tee. The broadband bias tee can be used to supply a voltage to the device and the DC feeder can be used to measure the bias voltage at the RF connector interface to compensate for the voltage drop due to the resistance of the inductance chain.

SHF offers two DC feeders, the SHF DF45, with a bandwidth of over 45 GHz, and the SHF DF65, with a bandwidth over 65 GHz.

Type
Bandwidth
tr/tf
Signal attenuation
Remarks
Dimensions (mm)
Datasheet

SHF DF45
DC Feeder

20 kHz - 45 GHz

<6 ps

<1 dB

16 V, 0.4 A

40 x 13 x 12.6

Datasheet

SHF DF65
DC Feeder

20 kHz - 65 GHz

<5 ps

<1 dB

16 V, 0.4 A

40 x 13 x 12.6

Datasheet