ADGM1004 Data Sheet
Rev. A | Page 12 of 20
TERMINOLOGY
Insertion Loss (IL)
IL is the amount of signal attenuation between the input and
output ports of the switch when the switch is in the on state.
Expressed in decibels, ensure that insertion loss is as small as
possible for maximum power transfer.
An example calculation of insertion loss based on the setup in
Figure 19 is as follows:
IL (dB) = −20log
10
|S
RF2RFC
|
where S
RF2RFC
is the transmission coefficient measured from RF2
to RFC with RF2 in the on position. All unused switches are in
the off position and terminated in a purely resistive load of 50 Ω.
Isolation (I
SO
)
I
SO
is the amount of signal attenuation between the input and
output ports of the switch when the switch is in the off state.
Expressed in decibels, ensure that isolation is as large as possible.
An example calculation of isolation based on the setup in Figure 20
is as follows:
I
SO
(dB) = −20log
10
|S
RFCRF1
|
where S
RFCRF1
is the transmission coefficient measured from RFC
to RF1 with RF1 in the off position. All unused switches are in
the off position and terminated in a purely resistive load of 50 Ω.
Crosstalk (C
TK
)
C
TK
is a measure of unwanted signals coupled through from one
channel to another because of parasitic capacitance.
An example calculation of crosstalk based on the setup in
Figure 21 is as follows:
C
TK
(dB) = −20log
10
|S
RF1RF2
|
where S
RF1RF2
is the transmission coefficient measured from RF1
to RF2 with RF1 in the off position and RF2 in the on position.
All unused switches are in the off position and terminated in a
purely resistive load of 50 Ω.
Return Loss (RL)
RL is the magnitude of the reflection coefficient expressed in
decibels, and the amount of reflected signal relative to the
incident signal.
An example calculation of return loss based on the setup in
Figure 19 is as follows:
RL (dB) = −20log
10
|S
11
|
where S
11
is the reflection coefficient of the port under test.
Third-Order Intermodulation Intercept (IIP3)
IIP3 is the intersection point of the fundamental P
OUT
vs. P
IN
extrapolated line and the third-order intermodulation products
extrapolated line of a two-tone test. IIP3 is a figure of merit that
characterizes the switch linearity.
Second-Order Intermodulation Intercept (IIP2)
IIP2 is the intersection point of the fundamental P
OUT
vs. P
IN
extrapolated line and the second-order intermodulation products
extrapolated line of a two-tone test. IIP2 is a figure of merit that
characterizes the switch linearity.
Second Harmonic (HD2)
HD2 is the amplitude of the second harmonic, where, for a signal
whose fundamental frequency is f, the second harmonic has a
frequency of 2 f. This measurement is a single-tone test,
expressed with reference to the carrier signal (dBc).
Third Harmonic (HD3)
HD3 is the amplitude of the third harmonic, where, for a signal
whose fundamental frequency is f, the third harmonic has a
frequency of 3 f. This measurement is a single tone test,
expressed with reference to the carrier signal (dBc).
On Switching Time (t
ON
)
t
ON
is the time it takes for the switch to turn on. It is measured
from 50% of the control signal (INx) to 90% of the on level. No
power was applied through the switch during this test (cold
switched). The switch was terminated into a 50 Ω load.
Off Switching Time (t
OFF
)
t
OFF
is the time it takes for the switch to turn off. It is measured
from 50% of the control signal (INx) to 10% of the on level. No
power was applied through the switch during this test (cold
switched). The switch was terminated into a 50 Ω load.
Settling Time Rising Edge
The settling time rising edge is the time it takes for the power of
an RF signal to settle within 0.05 dB of its final steady state
value. The switch was terminated into a 50 Ω load.
Settling Time Falling Edge
The settling time falling edge is the time it takes for the power
of an RF signal to settle within 0.05 dB of its final steady state
value. The switch was terminated into a 50 Ω load.
Actuation Frequency
The actuation frequency refers to the speed at which the
ADGM1004 can be switched on and off. Actuation frequency is
dependent on both settling times and on/off switching times.
Power-Up Time
The power-up time is a measure of the time required for the
device to power up and start to pass 90% of an RF input signal
after V
DD
has reached 95%.
Video Feedthrough
Video feedthrough is a measure of the spurious signals present
at the RFx ports of the switch when the control voltage is switched
from high to low or from low to high without an RF signal present.
Internal Oscillator Frequency
The internal oscillator frequency is the value of the on-board
oscillator that drives the gate control chip of the ADGM1004.
