Wideband Multifunction Reception System GaAs MMIC Completely Covers GPS
and CDMA
CXG1100TN
CXG1115ER
The gpsOne system is seen as a revolutionary technology for
the next generation of position information services. The gpsOne
system uses information from GPS satellites and the CDMA net-
work to complement each other and acquire reliable positioning
information. (See figure 1.)
A position information service that uses gpsOne cellular phones
is scheduled to start service this fall in Japan.
Sony has now developed a chip set that responds to the needs
of this market.
The CXG1100TN is a wideband DPDT switch, and the CXG1115ER
is a dual-mode front-end IC.
These devices adopt Sony’s unique JFET process and mounting
technologies to achieve high functionality and miniaturization.
CXG1100TN
s
s
s
s
s
s
s
Switching can be controlled from
CMOS lines
Wide bandwidth, low insertion loss,
and low distortion
Provided in an ultraminiature package
CXG1115ER
Dual band support
Circuit area reduced by the adoption
of 2× frequency multiplier technology
High gain, low noise, low distortion
Provided in an ultraminiature package
CXG1100TN DPDT Switch
Switching Can Be Controlled
from CMOS Lines
The CXG1100TN is a DPDT*
1
antenna
switch MMIC. While conventional
single band systems use a SPDT*
2
switch, the CXG1100TN supports dual-
band systems with DPDT operation. In
this device, Sony integrated logic
circuits on the same chip by using
Sony’s unique GaAs JFET E/D hybrid
process. This device can be directly con-
trolled from CMOS control lines.
for switching between two bands in the
quasi-microwave band. Furthermore, it
achieves a low insertion loss and low
distortion by adopting a Sony JFET pro-
cess that features single positive supply
voltage operation. (See table 1.)
mixer block, the CXG1115ER is able
to share a single LO circuit between two
systems. This reduces the circuit area,
and in addition to reducing costs, allows
a smaller package to be used providing
greater liberty in PWB mounting design.
CXG1115ER Low-Noise
Amplifier/Mixer
The CXG1115ER is a gpsOne low-
noise amplifier and downconversion
mixer IC that uses Sony’s GaAs JFET
process.
High Gain, Low Noise, Low
Distortion
One feature of the CXG1115ER is that
it achieves a good balance between high
gain, low noise, and low distortion. (See
figure 3.) Additionally, it also provides
a medium-gain mode to further improve
distortion characteristics and a low
power mode to conserve power. Appli-
cations can easily obtain desired char-
acteristics by controlling the control
switching inputs.
Wide Bandwidth, Low
Insertion Loss, and Low
Distortion
Since the CXG1100TN covers the wide
bandwidth of up to 3 GHz, it is optimal
Dual Band Support
The CXG1115ER receiver IC provides
a bypass switch in the CDMA system
low-noise amplifier block, can switch
gain appropriately for strong, medium,
and weak electric field reception con-
ditions, and furthermore provides a low-
current mode for standby operation. It
consists of two circuit systems, one for
the 850 MHz band CDMA system and
one for the 1575 MHz band GPS sys-
tem, and fully supports both CDMA and
GPS by providing a control switch.
Provided in Ultraminiature
Packages
The CXG1100TN is provided in a 10-
pin TSSOP (3.2
×
2.8 mm) package, and
the CXG1115ER is provided in a 24-
pin VQFN (4.0
×
4.0 mm) package.
These ultraminiature packages allow the
mounting area to be reduced signifi-
cantly.
*1
DPDT: Dual Pole Dual Throw
*2
SPDT: Singlel Pole Dual Throw
V
O
I
C
E
Our duty as chip designers is to
provide the market with ICs with
distinctive features and high
performance in a timely manner
and at a low price. The chip set
introduced here is a product that
meets all of these conditions,
and we are sure that our custom-
ers will find it more than satis-
factory.
Circuit Area Reduced by the
Adoption of 2× Frequency
Multiplier Technology
By doubling the frequency of the LO
input signal from the LO input (740
MHz) to 1480 MHz in the GPS system
Dual-band
antenna
TX block
IF block
GPS statellite
CXG1100TN
Dplx
CDMA RX
×2
GPS RX
CXG1115ER
Ext.
CDMA base station
IF block
s
Figure 1 Next-Generation Global Positioning Infor-
mation Service
s
Figure 2 CXG1100TN/CXG1115ER Application Circuit
CDMA LNA Representative Characteristics 1
Power Gain and Noise Figure vs. RF Frequency
16
15
14
13
12
11
10
9
8
7
6
800
820 840
860 880
fRF – RF frequency [MHz]
0
900
NF
2
1
3
Gp
5
CDMA Mixer Representative Characteristics 1
Conversion Gain and Noise Figure vs. RF Frequency
13
15
fLO = fRF – 110 MHz 12
14
LOin = –10 dBm
11
13
Gc
10
12
11
10
9
8
7
6
5
800
820 840
860 880
fRF – RF frequency [MHz]
NF
9
8
7
6
5
4
3
900
20
GPS LNA Representative Characteristics
Power Gain and Noise Figure vs. RF Frequency
5
19
GPS Mixer Representative Characteristics
Conversion Gain and Noise Figure vs. RF Frequency
13
11
Gc – Conversion gain [dB]
Gc – Conversion gain [dB]
Gc – Conversion gain [dB]
10
9
8
7
6
5
4
3
2
NF – Noise figure [dB]
NF – Noise figure [dB]
NF – Noise figure [dB]
17
16
15
14
13
12
11
Gp
10
9
8
7
NF
fLO = 1/2
×
(fRF – 110 MHz)
LOin = –10 dBm
6
5
4
3
2
1
NF
10
0
1525 1545 1565 1585 1605 1625
fRF – RF frequency [MHz]
3
1
1525 1545 1565 1585 1605 1625
fRF – RF frequency [MHz]
CDMA LNA Representative Characteristics 2
Output Power and IM3 vs. Input Power
20
10
0
Pout
CDMA Mixer Representative Characteristics 2
Output Power and IM3 vs. Input Power
20
10
0
Pout
s
Table 1
CXG1100TN Representative Electrical
Characteristics
(Ta
Symbol
Condition
900 MHz
1.58 GHz
900 MHz
1.58 GHz
50
Ω
*1
*1
*2
Typ.
0.35
0.46
22
17.2
1.2
–75
–75
60
25°C)
Unit
dB
dB
dB
dB
—
dBc
dBc
dBm
P
OUT
– RF output power [dBm]
–10
–20
–30
–40
–50
–60
–70
–80
–40
IM3
fRF1 = 850 MHz
fRF2 = 850.9 MHz
P
OUT
– RF output power [dBm]
–10
–20
–30
–40
–50
–60
–70
–80
–40
fRF1 = 850 MHz
fRF2 = 850.9 MHz
fLO = 740 MHz
LOin = –10 dBm
–30 –20
–10
0
Pin – RF input power [dBm]
10
IM3
Insertion loss
Isolation
VSWR
Harmonics
Input IP3
IL
ISO.
VSWR
2fo
3fo
IIP3
–30 –20
–10
0
Pin – RF input power [dBm]
10
*
1: Pin = 24 dBm, 0/3 V control, V
DD
= 3.0 V, 900 MHz
*
2: Pin = 24 dBm (900 MHz) + 24 dBm (901 MHz),
0/3 V control, V
DD
= 3.0 V
s
Figure 3 CXG1115ER Representative Characteristics
NF – Noise figure [dB]
Gp – Power gain [dB]
4
18
4
Gc
12
11
Embedded System
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