Front-end modules are
becoming hot wireless products
because of the great benefits
that they bring. The “front
end” is usually considered the
receiver low-noise amplifier
(LNA), the transmitter power
amplifier (PA), and the transmit/
receive (Tx/Rx) switch, as
well as any additional impedance
matching or filter components.
In past designs, all of these
components were individual
parts that required extra design
attentionnot to mention the extra board space. These parts
also added to the bill of materials
(BOM), increased cost,
and complicated procurement.
Now, putting all of these components
in one chip is a blessing
for designers.
The UPG2253T6S front-end
chip from California Eastern
Laboratories includes all of
those components, except for
the LNA. It targets Bluetooth
and IEEE 802.15.4/ZigBee
products in the 2.4-GHz band,
such as laptops, netbooks,
cell phones, and headsets. It’s
also a good fit for industrial
applications that use 802.15.4/
ZigBee modules for automatic
meter reading, wireless security,
cable replacement, lighting
systems, and other monitor
and control uses in homes or
commercial buildings.
The PA puts out 19 dBm
with a PAE of 28%. The second
harmonic is down –25
dB, and the third harmonic is
down –40 dB. The Tx/Rx
switch consists of two singlepole
double-throw (SPDT)
units. The IC’s through/PA
bypass feature enables the end
product to switch to a highpower
mode when greater
range is needed but automatically
switches to a low-power
mode when greater battery
savings are necessary. The
through/bypass path can also
be used as the Rx path. A lowpass
filter also is included.
The UPG2253T6S comes
in a 3- by 3- by 0.7-mm 12-pin
quad flat no-lead (QFN) package
(see the figure). According
to the company, this smaller
package size enables product
designs with tiny footprints,
while its better harmonic suppression
eliminates the need for
low-pass filters on most product
designs. The chip operates
from 3 V as well.
Shipping now, the
UPG2253T6S costs $1.10 in
100,000-unit quantities.
LOUIS E. FRENZEL
CALIFORNIA EASTERN LABORATORIESwww.cel.com