Evaluate: MAX2232/MAX2233
_________________________Quick Start
The MAX2232/MAX2233 EV kits are fully assembled
and factory tested. Follow the instructions in the
Connections and Signal Conditions section for proper
device evaluation.
Test Equipment Required
This section lists the test equipment recommended to
verify the operation of the MAX2232/MAX2233. It is
intended as a guide only and some substitutions are
possible:
• One DC power supply capable of supplying a mini-
mum of 1A from +2.7V to +5.5V
• One DC power supply capable of supplying a mini-
mum of 50mA from +2.7V to +5.5V
• HP 438A power meter or equivalent
• Digital multimeter (DMM) to monitor DC supply volt-
age and supply current (if desired)
• HP 8648C RF signal generator or equivalent 50Ω
sine wave source
• One 50Ω SMA cable (RG-58A/U or equivalent)
• One 20dB fixed attenuator capable of handling
+30dBm
Connections and Signal Conditions
1) Verify the DC power supply is set to less than +5.5V
and is turned off before connecting the supply to the
EV kit. A good starting point is +3.6V. Connect the
power supply between V
CC
and GND, and turn the
power supply on.
2) Verify jumper JU1 is in the V
CC
position, D1 / SHDN
= V
CC
. This enables the PA. Verify jumper JU2 is in
the V
CC
position, D0 / CTRL = V
CC
. This places both
the MAX2232 and MAX2233 in peak output power
mode. If desired, connect a second DC power sup-
ply to the center pin of jumper JU2 after removing the
shunt from JU2. This allows for experimentation with
the analog gain control feature of the MAX2232. Set
the CTRL voltage above 2.2V (do not exceed V
CC
)
for peak output power operation.
3) Connect the 20dB fixed attenuator to the EV kit’s
RFOUT SMA connector. Connect the attenuator’s
output to the power meter’s input. The 20dB attenua-
tor protects against overloading the input of the
power meter. Again, it is useful to measure the actu-
al loss of the attenuator with a properly calibrated
power meter. This is important for accurate output
power and power-added efficiency (PAE) measure-
ments. Enter the measured attenuation, plus 0.1dB
to compensate for SMA connector loss, as an offset
into the power meter.
4) Use a 50Ω SMA cable to connect a signal generator
to the RFIN SMA connector of the EV kit. Make sure
that the RF output of the signal generator is off. Set
the signal generator’s output frequency to 915MHz,
and adjust the output power level to deliver 0dBm to
the RFIN SMA connector of the EV kit. It is good
practice to use a properly calibrated power meter to
measure the power at the end of the cable prior to
connecting to the EV kit. This will account for cable
losses and signal generator inaccuracies to guaran-
tee that the correct signal level is delivered to the
PA. Consult the power meter’s operating manual for
proper calibration procedures.
Analysis
1) Turn on the RF output of the signal generator. The
power meter should nominally read +24dBm.
2) For the MAX2232, adjust the CTRL voltage from 0.6V
to 2.2V to vary the PA’s output power from 0dBm to
+24dBm. Adjust the CTRL voltage below 0.4V or
short jumper JU2 to ground to place the device in
standby mode. Refer to Table 1 in the MAX2232/
MAX2233 data sheet for operating modes.
3) For the MAX2233, adjust the logic-level signals to
vary the output power in 10dB steps. Refer to Table
2 in the MAX2232/MAX2233 data sheet for program-
ming output power levels.
MAX2232/MAX2233 Evaluation Kits
2 _______________________________________________________________________________________
Component Suppliers
SUPPLIER PHONE WEB
Taiyo
Yuden
408-573-4150
www.
t-yuden.com
Coilcraft 847-639-6400
www.
coilcraft.com
Murata 814-237-1431
www.
murata.com
FAX
408-573-4159
847-639-1469
814-238-0490
