NBB-500-D RFMD [RF Micro Devices], NBB-500-D Datasheet - Page 3

• Manufacturer Part Number: NBB-500-D
• Description: CASCADABLE BROADBAND GaAs MMIC AMPLIFIER DC TO 4GHz
• Manufacturer: RFMD [RF Micro Devices]

Rev A5 050414
Pin
1
2
3
4
Function
RF OUT
RF IN
GND
GND
Description
RF input pin. This pin is NOT internally DC blocked. A DC blocking
capacitor, suitable for the frequency of operation, should be used in
most applications. DC coupling of the input is not allowed, because this
will override the internal feedback loop and cause temperature instabil-
ity.
Ground connection. For best performance, keep traces physically short
and connect immediately to ground plane.
RF output and bias pin. Biasing is accomplished with an external series
resistor and choke inductor to V
DC current into this pin to a desired level. The resistor value is deter-
mined by the following equation:
Care should also be taken in the resistor selection to ensure that the
current into the part never exceeds maximum datasheet operating cur-
rent over the planned operating temperature. This means that a resistor
between the supply and this pin is always required, even if a supply
near 5.0V is available, to provide DC feedback to prevent thermal run-
away. Because DC is present on this pin, a DC blocking capacitor, suit-
able for the frequency of operation, should be used in most
applications. The supply side of the bias network should also be well
bypassed.
Same as pin 2.
R
=
(
------------------------------------------ -
V
CC
CC
. The resistor is selected to set the
–
I
V
CC
DEVICE
)
Interface Schematic
RF IN
NBB-500
RF OUT
4-51