RF2878PCBA-L datasheet(4/12 Pages) RFMD

4 / 12 page

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RF2878

Rev A0 060206

Function

Description

Interface Schematic

1RF IN

RF input pin. This pin is DC coupled and matched to 50

Ω at 836 MHz.

GND1

Ground connection. For best performance, keep traces physically short

and connect immediately to ground plane.

VPD

For low noise amplifier applications, this pin is used to control the bias

current. See plots for bias current settings. An external resistor (R1)

can be used to set the bias current for any VPD voltage.

For driver amplifier applications, this is the Power Down pin for the IC.

VPD=2.8V +/- 0.1V is required for proper operation. VPD< 0.9V turns

off the Part. External RF bypassing is required. The trace length

between the pin and the bypass capacitors should be minimized. The

ground side of the bypass capacitors should connect immediately to

ground plane. Nominal current required for VPD=2.8V is 2.0mA typical

and 3.0mA Max (@ VPD=2.9V).

4RF OUT

Amplifier Output pin. This pin is an open-collector output. It must be

biased to either VCC or pin 4 through a choke or matching inductor.

This pin is typically matched to 50

Ω with a shunt bias/matching induc-

tor and series blocking/matching capacitor. Refer to application sche-

matics.

GND2

Ground connection. For best performance, keep traces physically short

and connect immediately to ground plane.

RF IN

RF OUT

To Bias

Circuit

RF2878PCBA-L Datasheet(PDF) 4 Page - RF Micro Devices