Data Sheet

ADL8142

THEORY OF OPERATION

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Rev. 0 | 16 of 20

The ADL8142 is a GaAs, MMIC, pHEMT, low noise wideband am-

plifier with an integrated bias inductor and ac-coupling capacitors.

The simplified schematic is shown in Figure 63.

To adjust the drain bias current, connect an external resistor be-

tween the RBIAS and VDD pins.

The ADL8142 has ac-coupled, single-ended input and output ports

with impedances that are nominally equal to 50 Ω over the 23 GHz

to 31 GHz frequency range. No external matching components are

required. While the RF output path is ac-coupled, there is a dc path

to ground on the RFOUT side of the ac coupling capacitor.

Figure 63. Simplified Schematic