
Quadruple-Mode PCS/Cellular/GPS LNA/Mixers
Table 2. Modes of Operation
BAND
Cellular
PCS
GPS*
OPERATION MODE
HGHL
HGLL
MG
LG
ULG
HGHL
LG
ULG
GPS
LNA
HGHL
HGLL
MG
LG
LG
HGHL
LG
LG
GPS
MIXER
HL
LL
HL
LL
LG
HL
LL
LG
GPS
IF PORT
IF0 or IF1
IF0 or IF1
IF0 or IF1
IF0 or IF1
IF0 or IF1
IF0 or IF1
IF0 or IF1
IF0 or IF1
GIF
G2
0
0
0
1
1
0
1
1
0
G1
0
0
1
1
0
0
1
0
0
MODE
1
0
X
X
X
1
X
X
0
BAND
0
0
0
0
0
1
1
1
1
* MAX2530/MAX2531/MAX2537/MAX2538 only.
X = Don’t care.
Table 3. LO Frequency Plan
PART
MAX2351
MAX2354
MAX2358
MAX2359
MAX2530
MAX2531
MAX2537
MAX2538
VCO FREQUENCY
Cell Band VCO
Cell Band VCO
PCS Band VCO
PCS Band VCO
Cell and PCS Dual-Band VCO
Cell Band VCO
PCS Band VCO
PCS Band VCO
CELLULAR LO
FREQUENCY
f VCO
f VCO
0.5 x f VCO
—
f VCO
f VCO
0.5 x f VCO
0.5 x f VCO
PCS LO FREQUENCY
2 x f VCO
—
f VCO
f VCO
f VCO
2 x f VCO
—
f VCO
GPS LO
FREQUENCY
—
—
—
—
(2/3) f VCO
(4/3) f VCO
(2/3) f VCO
(2/3) f VCO
GPS Interstage
The GPS LNA and mixer include on-chip resonant tanks
that can be used instead of a saw filter for image sup-
pression. These tanks are coupled by an external L-C
network between pins 8 and 10 as shown in the Typical
Application Circuit .
Layout Considerations
Keep RF signal lines as short as possible to minimize
losses and radiation. Use controlled impedance on all
high-frequency traces. Use high-Q (>40) components
for the LNA input-matching circuit to achieve the lowest
possible noise figure. At the mixer outputs, keep the
differential signal lines together and of equal length to
ensure signal balance. For proper operation, solder the
exposed paddle evenly to the ground plane. Use abun-
dant ground vias between RF traces to minimize unde-
sired coupling.
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