SONY CXA3108AQ

CXA3108AQ
L-band Down Converter IC with On-Chip PLL
Description
The CXA3108AQ is a monolithic IC that downconverts the L-band (1 to 2 GHz) 1st IF to 2nd IF for
satellite broadcast receivers. It integrates a local
oscillator circuit, double-balanced mixer, IF AGC
amplifier and tuning PLL onto a single chip.
This IC supports both analog and digital satellite
broadcasts, and achieves reduction in the number of
tuner components and smaller size.
Features
• On-chip tuning PLL
• Supports 2.65 GHz oscillator frequency
• Noise figure: 12.5 dB typ. (for IF full gain)
•
•
•
•
•
IF AGC gain variation: 46 dB typ.
Wide band IF AGC amplifier (60 to 500 MHz)
Two IF outputs
PLL supports I2C protocol
On-chip high voltage drive transistor for charge
pump
40 pin QFP (Plastic)
Absolute Maximum Ratings (Ta=25 °C)
• Supply voltage
VCC
–0.3 to +5.5
V
• Storage temperature
Tstg –55 to +150 °C
• Allowable power dissipation
PD
730
mW
(when mounted on a substrate)
Operating Conditions
• Supply voltage
VCC
• Operating temperature
Topr
4.75 to 5.30
–25 to +75
V
°C
Applications
• Analog satellite broadcast tuners (BS/CS)
• Digital satellite broadcast tuners (DSS/DVB, etc.)
Structure
Bipolar silicon monolithic IC
Notes on Handling
This IC has a weak electrostatic discharge strength. Take care when handling the IC.
Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by
any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the
operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits.
—1—
E99904-TE
CXA3108AQ
XTAL
31
DGND1
32
NC
BUSSW
DVCC1
ADSW
SCL
SDA
ADC
LOCK
DVCC2
STSW
CPO
VT
Block Diagram and Pin Configuration
30
29
28
27
26
25
24
23
22
21
20 EXTIN2
Divider
11bit
REF
OSC
Phase
Detector
19 EXTIN1
33
I2C
Receiver
34
Lock
Det
18 DGND2
Shift
Register
17 GND
Charge
Pump
Buffer
Output Port
Driver
Divider
17 bit
STSW
PS1
35
PS2
36
PS3
37
PS4
38
16 OSCB2
Prescaler
1/2, 1/1
14 OSCE1
13 OSCB1
Buffer
GND
39
IFOUT2
40
15 OSCE2
OSC
Buffer
12 RFVCC
SAW
Driver
IF AGC
AMP
OUTPUT SW
SAW
Driver
MIX
11 BIAS
IFVCC2
7
8
9
10
RFGND
IFSW
6
IFGND1
IFGND2
5
RFIN2
4
RFIN1
3
IFAGC
2
IFVCC1
1
IFOUT1
IF VCC
—2—
CXA3108AQ
Pin Description
Pin
No.
Symbol
Pin voltage
[V]
IFOUT1
2.5
(IFSW 0 V)
4.7
(IFSW 5 V)
40
IFOUT2
4.7
(IFSW 0 V)
2.5
(IFSW 5 V)
2
IFGND2
0
1
Equivalent circuit
Description
4
IFVCC2
IF outputs.
1
40
IF output circuit GND.
4
IFVCC2
30k
3
IFSW
4
5
IFVCC2
IFVCC1
0 or 5
3
100k
5
5
Selects whether IF output is
Pin 1 or Pin 40.
When this pin is connected to
GND, the IF signal is output
from Pin 1; when connected to
VCC, the IF signal is output from
Pin 40.
IF output circuit power supply.
IF amplifier circuit power supply.
5
IFVCC1
6
6
IFAGC
0 to 4
AGC signal input.
40k
40k
7
RFIN1
1.7
7
8
2k
2k
RF inputs.
8
RFIN2
9
10
IFGND1
RFGND
1.7
0
0
IF amplifier circuit GND.
RF block GND.
—3—
CXA3108AQ
Pin
No.
Symbol
Pin voltage
[V]
Equivalent circuit
12
Description
RFVCC
Oscillator circuit current
adjustment.
Connect this pin to GND via a
capacitor.
200
11
BIAS
1.8
12
RFVCC
5
13
OSCB1
2.2
11
RF block power supply.
13
14
OSCE1
14
15
16
1.5
Oscillator pins.
2.5k
15
OSCE2
1.5
16
OSCB2
2.2
17
18
GND
DGND2
0
0
19
EXTIN1
2.5
2.5k
GND.
Charge pump GND.
30
DVCC1
25k
19
5k
5k
20k
20
EXTIN2
VT
25k
24
—
200
500
20k
22
CPO
PLL external inputs.
2.5
DVCC2
21
20
—
—4—
NPN transistor output for
varicap diode drive.
22
21
Charge pump output.
Connect a loop filter.
CXA3108AQ
Pin
No.
Symbol
Pin voltage
[V]
Equivalent circuit
Description
23
STSW
—
Selects either the internal
oscillator circuit or external input
for input to PLL.
When this pin is open or
connected to VCC, the internal
oscillator circuit is selected;
when connected to GND,
external input is selected.
24
DVCC2
5
Charge pump power supply.
30
DVCC1
20k
23
30
DVCC1
25
LOCK
5.0
(LOCK)
0.2
(UNLOCK)
25
30
26
ADC
—
LOCK detection.
High when locked, Low when
unlocked.
DVCC1
ADC input.
26
30
DVCC1
5k
27
SDA
—
DATA input.
27
20
2.5k
40k
—5—
CXA3108AQ
Pin
No.
Symbol
Pin voltage
[V]
Equivalent circuit
30
28
SCL
—
Description
DVCC1
CLOCK input.
28
30
DVCC1
150k
29
ADSW
1.3
I2C bus address selection.
29
50k
30
DVCC1
5
PLL circuit power supply.
30
DVCC1
30p
60k
31
XTAL
4.4
32
33
DGND1
NC
0
—
30p
31
Crystal connection for reference
oscillator.
PLL circuit GND.
—6—
CXA3108AQ
Pin
No.
Symbol
Pin voltage
[V]
Equivalent circuit
30
34
BUSSW
35
PS1
—
DVCC1
PLL circuit GND.
Connect directly to GND.
34
30
DVCC1
36
PS2
37
PS3
38
PS4
39
GND
Description
5.0
(OFF)
0.2
(ON)
35
36
Output ports.
37
38
0
GND.
—7—
CXA3108AQ
Electrical Characteristics
Circuit Current
Item
(VCC=5 V, Ta=25 °C)
Symbol
Circuit current A
AICC
Circuit current D
DICC
Measurement conditions
Analog circuit current
Sum of RFVCC, IFVCC1 and IFVCC2 currents
PLL circuit current
Sum of DVCC1 and DVCC2 currents
Min.
Typ.
Max.
Unit
42
62
82
mA
18
30
40
mA
Measurement conditions
fin=950 MHz, fIF=480 MHz
IFAGC=4 V (Full Gain)
fin=1450 MHz, fIF=480 MHz
IFAGC=4 V (Full Gain)
fin=2150 MHz, fIF=480 MHz
IFAGC=4 V (Full Gain)
fin=950 MHz, fIF=480 MHz
IFAGC=4 V (Full Gain)
fin=1450 MHz, fIF=480 MHz
IFAGC=4 V (Full Gain)
fin=2150 MHz, fIF=480 MHz
IFAGC=4 V (Full Gain)
Min.
Typ.
Max.
Unit
15
21
25
dB
14
20
24
dB
18
24
28
dB
13
16
dB
13
16
dB
13
16
dB
OSC/MIX/IF Amplifier Blocks
Item
Symbol
CG1
Conversion gain
CG2
CG3
NF1
Noise figure
NF2
NF3
IFAGC gain variation
range
AGC
IF maximum output
PoSAT
RF pin local oscillator
leak
IF pin local oscillator
leak
RFLK1
RFLK2
RFLK3
IFLK1
IFLK2
IFLK3
Tertiary intermodulation
IM3
distortion
Local oscillator phase
noise
RF input impedance
CN1
CN2
rπ
Cπ
35
fIF=480 MHz,
50 Ω load saturated output
fOSC=1430 to 1830 MHz
fOSC=1830 to 2230 MHz
fOSC=2230 to 2630 MHz
fOSC=1430 to 1830 MHz
fOSC=1830 to 2230 MHz
fOSC=2230 to 2630 MHz
Pin=–25 dBm
IFAGC=4 V (Full Gain)
fin=935 MHz, 940 MHz
fout=475 MHz, 480 MHz
S/I of 480 MHz and 475 MHz
fOSC=1430 MHz
10 kHz offset
fOSC=1430 MHz
100 kHz offset
f=950 MHz
f=950 MHz
—8—
50
dB
9
dBm
–20
–20
–25
–18
–18
–20
38
dBm
dBm
dBm
dBm
dBm
dBm
45
dB
80
dBc/Hz
100
dBc/Hz
12.9
1.84
Ω
pF
CXA3108AQ
PLL Block
Item
External local input level
SDA, SCL
High level input voltage
Low level input voltage
High level input current
Low level input current
SDA Low output voltage
Clock input hysteresis
CPO (charge pump)
Output current 1
Output current 2
ADC
Input current
LOCK
High output voltage
Low output voltage
REFOSC
Oscillator frequency range
Input capacitance
Drive level
PS1 to PS4
Pull-in current
Leak current
Symbol
EXT
VIH
VIL
IIH
IIL
LSDA
CIHYS
Measurement conditions
Typ.
–20
3
GND
Byte 4/bit 6=0 and for 3WB
Byte 4/bit 6
IADC
Input voltage=5 V
VLKH
VLKL
Load resistance 10 kΩ, for LOCK
Load resistance 10 kΩ, for UNLOCK
FXTOSC
CXTOSC
VXTOSC
Max.
Unit
dBm
V
V
µA
µA
V
V
µA
µA
0.25
0.4
VCC
1.5
–0.1
–2
0.4
0.65
±35
±125
±50
±180
±75
±270
VIH=VCC
VIL=GND
Sink current=3 mA
ICPO1
ICPO2
SinkPS
LeakPS
Min.
0
–1
0.2
3
µA
VCC
0.5
V
V
12
MHz
pF
mV
1
200
mA
nA
Max.
Unit
400
kHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
14
200
When ON
When OFF
Bus Timing
Item
Bus
SCL clock frequency
Start waiting time
Start hold time
Low hold time
High hold time
Start setup time
Data hold time
Data setup time
Rise time
Fall time
Stop setup time
Symbol
Measurement conditions
Min.
Typ.
I2C
fSCL
tWSTA
tHSTA
tLOW
tHIGH
tSSTA
tHDAT
tSDAT
tR
tF
tSSTO
0
1300
600
1300
600
600
1300
600
300
300
600
—9—
IFout1
1n
IFSW
CXA3108AQ
68n
EXTIN2
20
1n
40
1
IFOUT1
IFOUT2
39 GND
38 PS4
37 PS3
36 PS2
35 PS1
34 BUSSW
2
3
4
5
7
6
100p 100p
9
8
10
1n
BIAS 11
RFVCC 12
OSCB1 13
OSCE1 14
OSCE2 15
OSCB2 16
GND 17
DGND2 18
IFVCC1
33 NC
RFIN2
EXTIN1 19
XTAL
IFGND1
32 DGND1
31
IFAGC
IFAGC
100p
21
22
23
24
25
26
27
28
29
30
DVCC1
6.2k 330n
ADSW
10k
SCL
IFGND1
SDA
SCL
ADC
SDA
LOCK
IFVCC2
DVCC2
ADCin
STSW
RFGND
—10—
RFin
IFout2
5V
LOCK
CPO
RFIN1
VT
Electrical Characteristics Measurement Circuit
0.1µ
15p
15p
1n
1n
1µ
1k
1T379
1k
1T379
1k
10k
30V
5V
EXTIN
CXA3108AQ
CXA3108AQ
Description of Functions
The CXA3108AQ is a tuner IC for satellite broadcast receivers. It converts the RF signal down-converted to
1st IF (1 to 2 GHz) at the LNB to 2nd IF, so that only the desired reception frequency is selected and
detected.
This IC combines the mixer, local oscillator and IF amplifier (variable gain) circuits required for frequency
conversion to 2nd IF, and the PLL circuit which controls the local oscillator frequency onto a single chip.
The function of each block is described below.
1. Mixer Circuit
This circuit outputs the frequency difference between the signal input to RF IN and the local oscillator
signal. A double-balanced mixer with minimal local oscillator signal leak is used. RF input is equivalent to a
differential amplifier with emitter grounding.
2. Local Oscillator Circuit
A Colpitts oscillator with differential operation is used for the oscillator circuit, so it is stable relative to
supply voltage fluctuation, and undesired radiation is suppressed. This circuit also contains a capacitor
which is part of the resonance circuit, so there is minimal parasitic oscillation and design of external circuits
is easier.
3. IF Amplifier Circuit
This circuit amplifies the mixer IF output, and is comprised of an AGC amplifier stage and low impedance
output stage.
The gain can be varied by the AGC pin voltage (range 0 to 4 V) at the AGC amplifier stage. The maximum
gain is approximately 20 dB (voltage gain between RF IN and IF OUT), and the gain variation width is 30
dB or more.
The output stage has two unbalanced outputs, and can directly connect two SAW filters with different pass
bandwidths. Output pin selection is determined by the IF SW pin voltage.
The IF amplifier circuit is a wide band amplifier circuit, and can be used in the IF frequency range of 60 to
500 MHz.
4. PLL Circuit-1 (normal operation: when the STSW pin is open or connected to VCC)
The PLL circuit fixes the local oscillator frequency to the desired frequency. It consists of the prescaler,
main divider, reference divider, phase comparator, charge pump and reference oscillator. The control
format supports the I2C bus protocol.
When the power (DVCC1) is turned on, the power-on reset circuit activates and the frequency division data
and control data are all initialized to 0. The power-on reset threshold is 3 V at normal temperature (Ta=25
°C).
5. PLL Circuit-2 (external input PLL operation: when the STSW pin is connected to GND)
When the STSW pin is connected to GND, the PLL enters independent operation mode where the PLL only
is used with the oscillator signal input from the external signal input pin.
—11—
CXA3108AQ
Description of PLL Block
1. Programming
1-1. The main divider frequency division ratio is obtained according to the following formulas.
fosc = fref × (16M + S) or fosc = fref × 2 × (16M + S) (when PE = 1)
fosc : local oscillator frequency
fref : comparison frequency
2 : prescaler fixed frequency division ratio (when PE = 1)
M : main divider frequency division ratio
S : swallow counter frequency division ratio
The variable frequency division ranges of M and S are as follows.
S ≤ M ≤ 4095
0 ≤ S ≤ 15
During PLL independent operation (STSW = GND), the prescaler halving frequency division cannot be
added.
1-2. I2C Bus
This IC conforms to the standard I2C bus format, and bidirectional bus control is possible consisting of a
write mode in which various data are received and a read mode in which various data are sent.
Write and read modes are recognized according to the setting of the final bit (R/W bit) of the address
byte. Write mode is set when the R/W bit is “0”, and read mode is set when the R/W bit is “1”.
1-2-1. Address Setting
The responding address can be changed by the ADSW pin voltage to allow more than one PLL in a
system.
<Table 1> Address
ADSW pin voltage
0 to 0.1 VCC
OPEN
0.4 VCC to 0.6 VCC
0.9 VCC to VCC
MA1
0
0
1
1
MA0
0
1
0
1
—12—
CXA3108AQ
1-2-2. Data format
Write mode is used to receive various data. In this mode, byte 1 contains the address data, bytes 2 and
3 contain the frequency data, and bytes 4 and 5 contain the various control data.
These data are latch transferred in the manner of byte 1, byte 2 + byte 3, byte 4, and byte 5. When the
correct address is received, the data is recognized as frequency data if the first bit of the next byte is
“0”, and as control data if this bit is “1”.
Also, when data transmission is stopped part-way, the previously programmed data is valid. Therefore,
once the control data has been programmed, 3-byte commands consisting of the address and
frequency data are possible.
Further, even if the I2C bus stop conditions are not met, data can be input by sending the start
conditions and the new address.
In read mode, the power-on reset operation status, phase comparator locked/unlocked status and 5value A/D converter input pin voltage status are transmitted to the master.
Power-on reset is set to “1” when the supply voltage (DVCC1) power supply is cut off.
If DVCC1 is 3 V or higher and the status is output in the read mode, this bit is reset to “0”.
Write mode: slave receiver
MODE
Address byte
Divider byte 1
Divider byte 2
Control byte 1
Control byte 2
MSB
bit7
1
0
M3
1
OS
bit6
1
M10
M2
M12
CP
bit5
0
M9
M1
M11
0
bit4
0
M8
M0
PE
0
bit3
0
M7
S3
R3
P4
bit2
MA1
M6
S2
R2
P3
bit1
MA0
M5
S1
R1
P2
LSB
bit0
0
M4
S0
R0
P1
bit7
1
PR
bit6
1
FL
bit5
0
1
bit4
0
1
bit3
0
1
bit2
MA1
A2
bit1
MA0
A1
bit0
1
A0
Read mode: slave transmitter
MODE
Address byte
Status byte
—13—
A
A
A
A
A
CXA3108AQ
P1 to P4
M0 to M12
S0 to S3
OS
CP
PE
PR
FL
A0 to A2
R0 to R3
:
:
:
:
:
:
:
:
:
:
port control
main divider frequency division ratio setting
swallow counter frequency division ratio setting
varicap output OFF (when “1”)
charge pump current switching
prescaler halving frequency division added (when “1”)
power-on reset
lock detection signal
5-value ADC data (ADC pin voltage conversion: Table 2)
reference divider frequency division ratio selection (Table 3)
<Table 2> ADC Conversion Table
ADC pin voltage
0 to 0.15VCC
0.15 VCC to 0.3 VCC
0.3 VCC to 0.45 VCC
0.45 VCC to 0.6 VCC
0.6 VCC to VCC
A2
0
0
0
0
1
A1
0
0
1
1
0
A0
0
1
0
1
0
<Table 3> Reference Divider Frequency Division Ratio
R3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
R2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
R1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
R0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
—14—
Frequency division ratio
2
4
8
16
32
64
128
256
—
5
10
20
40
80
160
320
CXA3108AQ
I2C Bus Timing Chart
tWSTA
SDA
tR
tSSTA
tF
tSSTO
SCL
tHSTA
START
tLOW
tHIGH
tSDAT
CLOCK
tHDAT
DATA CHANGE
tSSTA =Start setup time
tWSTA =Start waiting time
tHSTA =Start hold time
tLOW =LOW clock pulse width
tHIGH =HIGH clock pulse width
tSDAT
tHDAT
tSSTO
tR
tF
—15—
=Data setup time
=Data hold time
=Stop setup time
=Rise time
=Fall time
STOP
CXA3108AQ
Example of Representative Characteristics
Current consumption characteristics
ICC - Current consumption [mA]
100
95
90
85
75
4.6
4.7
4.8
4.9
5
5.1
5.2
5.3
5.4
VCC Supply voltage [V]
Conversion gain
IF=480MHz, AGC=4V
25
CG - Conversion gain [dB]
IFOUT
20
15
10
5
0.8
1
1.2
1.4
1.6
RF input frequency [GHz]
NF characteristics IF=480 MHz, AGC=4V
Untuned input, DSB display
NF - Noise figure [dB]
20
15
10
5
0
0.8
1
1.2
1.4
1.6
1.8
2
RF input frequency [GHz]
—16—
2.2
1.8
2
2.2
CXA3108AQ
RF pin local oscillator leak characteristics
RF pin local oscillator leak [dBm]
–10
–20
–30
–40
–50
–60
1.4
1.6
1.8
2
2.2
2.4
2.6
2.8
fOSC - Local oscillator frequency [GHz]
IFOUT pin local oscillator leak characteristics
AGC=4V
IFOUT pin local oscillator leak [dBm]
–10
–20
–30
–40
–50
–60
1.4
1.6
1.8
2
2.2
2.4
fOSC - Local oscillator frequency [GHz]
Input/output characteristics (untuned input, AGC=4V)
20
10
Fundamental wave (480MHz)
0
IF output level [dBm]
–10
–20
–30
–40
–50
–60
Tertiary intermodulation
distortion component (470MHz)
–70
–60
–50
–40
–30
–20
–10
0
10
RF input level [dBm] (935MHz, 940MHz)
—17—
2.6
2.8
CXA3108AQ
Input Impedance
3
2150MHz
1
950MHz
2
1450MHz
Output Impedance
479.5MHz
1
—18—
CXA3108AQ
Unit : mm
40PIN QFP (PLASTIC)
+ 0.35
1.5 – 0.15
+ 0.1
0.127 – 0.05
9.0 ± 0.4
+ 0.4
7.0 – 0.1
0.1
21
30
20
31
A
11
40
1
+ 0.15
0.3 – 0.1
0.65
10
0.24
M
(8.0)
+ 0.15
0.1 – 0.1
0° to 10°
0.5 ± 0.2
Package Outline
DETAIL A
PACKAGE STRUCTURE
PACKAGE MATERIAL
EPOXY RESIN
SONY CODE
QFP-40P-L01
LEAD TREATMENT
SOLDER / PALLADIUM
PLATING
EIAJ CODE
QFP040-P-0707
LEAD MATERIAL
42/COPPER ALLOY
PACKAGE MASS
0.2g
JEDEC CODE
—19—