GSM/UMTS Dual Mode Terminal Ultralow Loss Antenna Switch Module
CXG1190EQ/AEQ
Portable telephone terminals are seeing rapid advances in functional-
ity as easily handheld devices.
The third generation cellular phone service is poised to take off on a
worldwide scale.
The CXG1190EQ/AEQ are antenna switching modules that support dual
mode operation for both GSM, which holds an large share worldwide,
and UMTS, which is the third generation cellular phone standard.
In addition to both multiband and multimode support, the CXG1190EQ/
AEQ are high-performance lead frame modules that achieve low inser-
tion loss and a miniature low-height form factor.
These modules support the creation of wireless equipment that remains
one step ahead using Sony鈥檚 MMIC technologies.
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Ultralow insertion loss: 0.9 dB in the
DCS/PCS Tx path and 0.65 dB in the
UMTS (Rx) path
Dual low-pass filters:
Attenuation 30 dB typical
(GSM Tx 2fo, DCS/PCS Tx 2fo)
Lead frame module that adopts a mold
array package
Miniature low-height package:
LQFN-28P-01
(4.5 mm
脳
3.2 mm
脳
1.3 mm max.)
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Switching Structure that
Achieves Low Insertion Loss
Insertion loss is an important index for
switch performance.
Switch modules using the conventional
LTCC* substrate adopted a structure in
which the frequency band was divided into
a low band (900 MHz band) and a high
band (1800/1900 MHz band) using a
diplexer, and after that, the path switches
were connected. (See figure 1.) The switch
structure adopted by Sony in these prod-
ucts is the SP7T structure. A low-pass
filter is inserted in the GSM Tx path. (See
figure 2.) In the conventional LTCC mod-
ule structure, the insertion loss for all of
the paths was the sum of the diplexer and
the path switches themselves. As a result,
the overall loss was quite large.
In contrast, in the SP7T structure, only the
switch insertion loss occurs in the paths
other than the GSM Tx path, thus achiev-
ing low loss. For the GSM Tx path, the
SP7T + LPF structure can achieve lower
loss than the diplexer structure since a LPF
has smaller insertion loss than a diplexer.
Furthermore, these devices achieve
ultralow loss by using Sony鈥檚 unique
JPHEMT process. This contributes sig-
nificantly to reduced current consumption
during Tx and higher Rx sensitivity.
*:
LTCC: Low temperature co-fired ceramic
number of changes to the assembly pro-
cess in current manufacturing lines. This
contributes to lowering the cost of the de-
vices. Since handling is only required for
two simple components, an IC and a low-
pass filter, Sony was able to shorten the
development turn around time. Also, the
adoption of a package with a proven track
record in the market has the advantage that
customers can use these devices with con-
fidence.
Lead Frame Module
Conventional antenna switch modules
used in GSM terminals and other prod-
ucts adopt a structure in which passive and
active elements, such as PIN diodes, are
mounted on an LTCC, FR-4 or similar
substrate. However, considering the
demands for multimode and multiband op-
eration, miniature low-height form factors,
and lower costs in recent cellular phone
products, it can easily be seen that it will
be difficult to achieve these using these
conventional structures. Sony鈥檚 response
to these issues was implemented using the
mold array package, which uses lead
frames, an existing package technology.
By adopting an existing package that uses
lead frames, Sony was able to assure the
pin count required for the increase in the
number of switches due to the use of
multimode and multiband operation. Fur-
thermore, this made further miniaturiza-
tion easy.
Another advantage was that it was pos-
sible to keep to an absolute minimum the
Miniature Low-Height Form
Factor
The mounting area was reduced by mak-
ing the two low-pass filters integrated in
the two Tx paths into one component
using LTCC technology. Also, etching
technology can be used to perform com-
plicated machining on the lead frame,
which plays the role of interface between
the internal components. That technology
is used for the connections for the inter-
nal low-pass filters in these products. Fur-
thermore, Sony optimized the contact area
between the internal low-pass filter lands
and the lead frame and also optimized the
mold sealing thickness above the low-pass
filters, thus achieving a miniature low-
height form factor.
V
O
I
C
E
The CXG1190EQ/AEQ ICs could
only have been developed by
Sony, and were developed from
Sony鈥檚 unique perspective, a per-
spective unknown at other compa-
nies. These devices are already
earning an enthusiastic response
in the market. We are now plan-
ning new products that deploy this
technology. Keep your eye on
Sony鈥檚 MMIC technologies!
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