VMMK-2103-BLKG Avago Technologies US Inc., VMMK-2103-BLKG Datasheet - Page 9

• Manufacturer Part Number: VMMK-2103-BLKG
• Description: GaAsCap Amplifier
• Manufacturer: Avago Technologies US Inc.

Specifications of VMMK-2103-BLKG

• Current - Supply: 24mA
• Frequency: 500MHz ~ 6GHz
• Gain: 14dB
• Noise Figure: 2.1dB
• P1db: 0dBm
• Package / Case: 0402 (1005 Metric) - 1.00mm L x 0.50mm W x 0.25mm H
• Rf Type: Cellular, PCS
• Test Frequency: 3GHz
• Voltage - Supply: 5V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 516-2216; VMMK-2103-BLKG

VMMK-2103 Application and Usage
(Please always refer to the latest Application Note AN5378 in website)
Biasing and Operation
The VMMK-2103 can be used as a low noise amplifier or as a
driver amplifier. The nominal bias condition for the VMMK-
2103 is Vd = Vc = 5V. At this bias condition, the device provides
an optimal compromise between power consumption, noise
figure, gain, power output, and OIP3. The VMMK-2103 is
biased with a positive supply connected to the output pin Vd
through an external user supplied bias decoupling network
as shown in Figure 19. A control voltage Vc is applied to
the input pin through a similar bias decoupling network.
The VMMK-2103 operates in the gain mode when Vc=Vd.
Nominal Vd is between 3 and 5 V. When Vc is at 0V, the device
is biased in the “bypass” mode, which engages the integrated
bypass switch which then shuts down the amplifier.
Figure 19. Example application of VMMK-2103 at 3GHz
The output bias decoupling network can be easily con-
structed using small surface mount components. The value
of the output inductor can have a major effect on both
low and high frequency operation. The demo board uses
a 15 nH inductor that has a self resonant frequency higher
than the maximum desired frequency of operation. If the
self-resonant frequency of the inductor is too close to the
operating band, the value of the inductor will need to be
adjusted so that the self-resonant frequency is significantly
higher than the highest frequency of operation.
Typically a passive component company like Murata does
not specify S parameters at frequencies higher than 5 or
6 GHz for larger values of inductance making it difficult
to properly simulate amplifier performance at higher
frequencies. It has been observed that the Murata LQW15AN
series of 0402 inductors actually works quite well above their
normally specified frequency. As an example, increasing the
output inductor from 15 nH to 39 nH provides bandwidth
from 200 MHz through 6 GHz with good gain flatness.
Further extending the low frequency response of the VMMK-
2103 is possible by using two different value inductors in
series with the smaller value inductor placed closest to the
device and favoring the higher frequencies. The larger value
inductor will then offer better low frequency performance by
not loading the output of the device.
9
Input
0.1 uF
22 nH
100 pF
50 Ohm line
Vc
Input
Pad
Amp
Ground
Pad
Output
Pad
50 Ohm line
0.1 uF
100 pF
Vdd
15 nH
100 pF
Output
Figure 20. Evaluation/Test Board (available to qualified customer request)
The parallel combination of the 100pF and 0.1uF capacitors
provide a low impedance in the band of operation and at
lower frequencies and should be placed as close as possible
to the inductor. The low frequency bypass provides good
rejection of power supply noise and also provides a low
impedance termination for third order low frequency mixing
products that will be generated when multiple in-band
signals are injected into any amplifier.
The input bias decoupling network is similar to that used on
the output. A 22 nH inductor bypass with a 100pF capacitor
provides a means to control Vc on the input port. Since there
is a voltage developed internally to the VMMK-2103 at the
input terminal, any resistance in series with the power supply
will actually raise the input terminal above ground enough
that it begins to affect linearity in the bypass mode. Switching
time between the gain mode and the bypass mode is under
0.1 Psec. If switching speed is not a high priority, then the
bypass capacitor on the input should be raised to 0.1 uF to
help minimize noise and spurious from the power supply
adversely affecting the operation of the VMMK-2103.
S Parameter Measurements
The S parameters are measured on a 300um G-S-G (ground
signal ground) printed circuit board substrate. Calibration is
achieved with a series of through, short and open substrates
from which an accurate set of S parameters is created. The
test board is .016 inch thickness RO4350. Grounding of the
device is achieved with a single plated through hole directly
under the device. The effect of this plated through hole is
included in the S parameter measurements and is difficult
to de-embed accurately. Since the maximum recommended
printed circuit board thickness is nominally .020 inch, then
the nominal effect of printed circuit board grounding can be
considered to have already been included the published S
parameters.
The product consistency distribution charts shown on page
2 represent data taken by the production wafer probe station
using a 300um G-S wafer probe. The ground-signal probing
that is used in production allows the device to be probed
directly at the device with minimal common lead induc-
tance to ground. Therefore there will be a slight difference
in the nominal gain obtained at the test frequency using the
300um G-S wafer probe versus the 300um G-S-G printed
circuit board substrate method.