EVAL-ADGM1004EBZ User Guide
UG-1078
Rev. 0 | Page 3 of 11
EVALUATION BOARD HARDWARE
The
ADGM1004
evaluation kit contains a fully fitted, printed
circuit board (PCB).
The
EVAL-ADGM1004EBZ
evaluation board allows the user to
connect RF signals to the MEMS switch. The user controls the
switch operation using the on-board links or by applying the
correct control signals to the appropriate connectors.
The
EVAL-ADGM1004EBZ
provides an additional transmission
line to facilitate the calibration of the network analyzer to
minimize the effects of the PCB tracks that connect the RF
signals to the MEMS switch. This user guide describes the
calibration process in detail (see the Network Analyzer
Calibration Procedure section).
POWER SUPPLY
To operate the
EVAL-ADGM1004EBZ
, the user must provide
an external power supply connected to the power block, P1.
The supply voltage is 3.3 V and must be positive with respect
to the ground of the
EVAL-ADGM1004EBZ
. The ground of the
EVAL-ADGM1004EBZ
is marked with GND on the silkscreen
near P1 (see Figure 12).
RF CONNECTORS
The SMA edge connectors on the
EVAL-ADGM1004EBZ
(RF1
to RF4 and RFC) connect to each switch in the
ADGM1004
for
performance evaluation purposes. The RF5 and RF6 connectors
connect to a transmission line to estimate the loss associated with
the PCB (see the Measuring Switch Performance section). Table 1
describes the RF connectors to the
ADGM1004
.
Table 1. Connecting the RF Connectors to the
ADGM1004
Connector
Description
RF1
Port RF1 of the
ADGM1004
RF2
Port RF2 of the
ADGM1004
RF3
Port RF3 of the
ADGM1004
RF4
Port RF4 of the
ADGM1004
RFC
Common RF port of the
ADGM1004
RF5, RF6
CALIBRATION THRU transmission lines used for
calibration
SWITCH CONTROL CONNECTORS
The control integrated circuit (IC) packaged with the MEMS
switch internally generates the voltage required to drive the switch.
The internal control IC contains a reference clock signal at a
nominal 11.5 MHz. In normal operation, set the (EXTD_EN)
link to low, enabling the built-in 11.5 MHz oscillator to enable
the internal driver IC voltage boost circuitry. Note that in Figure 1,
this link is shown in parentheses on the evaluation board. Set
(EXTD_EN) to high to disable the internal 11.5 MHz oscillator and
drive V
CP
with 80 V dc from the external voltage supply. Disabling
the internal oscillator eliminates the associated 11.5 MHz noise
feedthrough into the switch. With the oscillator disabled, the
logic interface pins (IN1 to IN4) still control the switch.
The
ADGM1004
comes with a standard LVTTL parallel interface
consisting of four input pins, IN1 to IN4. The logic level applied to
the IN1 through IN4 inputs controls the state of the MEMS
switches.
Table 2. (EXTD_EN) Link Position
Position
Reference Clock Setting
Low (default)
Built in 11.5 MHz oscillator enable
High
Disables the internal oscillator
(RF1), (RF2), (RF3), and (RF4) Mode Mode of Operation
The IN1 to IN4 input pins control the switch state and operation
mode of the
ADGM1004
. The
EVAL-ADGM1004EBZ
allows the
user to control these pins by using the (RF1) to (RF4) links or
by applying external signals to the SMB connectors, IN1 to IN4,
respectively (see Table 3).
