MAX2320/21/22/24/26/27 Evaluation Kits
3) Connect one RF signal generator to the LNAINL
Testing the Mixer
1) Connect a DC supply set to +2.7V (through an
ammeter if desired) to the VCC and GND terminals
on the EV kit. If available, set the current limit to
40mA.
(LNAINH) SMA connector for cellular (PCS) band
testing. Do not turn on the generator’s output. Set
the generator for an output frequency of 881MHz
(1960MHz) for cellular (PCS) band operation. Set
the power level to -25dBm.
2) Install the shunts across jumpers JU5 and JU8.
Install the shunt across JU6 to the FMMXR position
(except MAX2322; see Table 5) and across JU4 to
OFF. See Tables 1–4 for positions of the shunts
across JU1, JU2, and JU3 for different modes.
4) Connect the spectrum analyzer to the LNAOUTL
(LNAOUTH) SMA connector for cellular (PCS) band.
Set the center frequency to 881MHz (1960MHz) for
cellular (PCS) band, and span to 5MHz.
5) Turn on the RF signal generator. The peak that
appears on the spectrum analyzer should have a
magnitude of about -11dBm in high-gain and FM
modes. In low-gain modes, the magnitude should
be about -27dBm. Be sure to account for cable
losses (between 0.5dB and 2dB) and circuit board
losses (approximately 0.5dB) when computing gain
and noise figure.
3) Connect an RF signal generator to the MIXINL (MIX-
INH) SMA connector for cellular (PCS) band testing.
Do not turn on the generator’s output. Set the gener-
ator for an output frequency of 881MHz (1960MHz)
for cellular (PCS). Set the power level to -25dBm.
4) See Table 5, and connect the second RF signal gen-
erator to the appropriate LO connector and set the
frequency accordingly. Set the power level to
-6dBm.
6) (Optional) Another method for determining gain is
by using a network analyzer. This has the advan-
tage of displaying gain over a swept frequency
band, in addition to displaying input and output
return loss. Refer to the network analyzer manufac-
turer’s user manual for setup details.
5) In FM mode, connect the spectrum analyzer con-
nector to the FMOUT SMA, set the center frequency
to 110MHz, and span to 5MHz. For all other modes,
connect the spectrum analyzer connector to the
CDMAOUT SMA and set the center frequency to
210MHz and span to 5MHz.
Table 3. MAX2324 Mode Selection
JU2 SHUNT
POSITION*
JU1 SHUNT
POSITION
JU3 SHUNT
POSITION
MODE
PCS
CELL
CELL
CELL
CELL
Don’t care
HLIN
Don’t care
HGAIN
LGAIN
Shutdown
Cellular band, high gain, high linearity
Cellular band, low gain, high linearity
Cellular band, high gain, low linearity
FM
HLIN
LLIN
HGAIN
LGAIN
LLIN
*JU2 is connected to the MAX2324 SHDN pin.
Table 4. MAX2327 Mode Selection
JU2 SHUNT
POSITION
JU1 SHUNT
POSITION*
JU3 SHUNT
POSITION
MODE
Don’t care
CELL
CELL
PCS
LLIN
HLIN
HLIN
HLIN
HLIN
Don’t care
HGAIN
LGAIN
Shutdown
Cellular band, digital mixer output
Cellular band, FM
HGAIN
LGAIN
PCS band, digital mixer output
Not used
PCS
*JU1 is connected to the MAX2327 SHDN pin.
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