SONY CXA3038N

CXA3038N
IQ Detection IC for Digital Satellite Broadcast Tuner
Description
The CXA3038N is an IC for IQ-detection of DSS,
DVB, and other digital satellite broadcast QPSK
modulation signals in the 480 MHz band. It consists
of an AGC amplifier circuit, oscillator circuit, phase
shifter circuit, and phase comparison circuit. In
addition, the chip has a PLL circuit for frequency
control and built-in control data. It realizes highaccuracy oscillator frequencies through use of a lowcost LC resonance circuit.
Features
• Built-in PLL for controlling oscillator frequency.
• Oscillator frequency based at 479.5 MHz is
adjustable in ±4 steps of 50 kHz using the voltage
of the control pin.
• Reference OSC allows switching to 4 MHz or 10
MHz.
• Built-in output buffer for reference OSC.
• Low-impedance IQ output.
• AGC gain variation 35 dB.
24 pin SSOP (Plastic)
Absolute Maximum Ratings (Ta=25 °C)
• Supply voltage
VCC
–0.3 to 5.5
• Storage temperature
Tstg –55 to +150
Operating Conditions
• Supply voltage
VCC
• Operating temperature
Topr
4.75 to 5.30
–25 to +75
V
°C
V
°C
Applications
Digital satellite broadcast tuner
Structure
Bipolar silicon monolithic 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—
E97650A84-TE
CXA3038N
XTAL
LOCK
REFOUT
DVCC
DGND
LPF
VC
OSCGND
OSC1
OSC2
PSVCC
LOOUT
Block Diagram and Pin Configuration
24
23
22
21
20
19
18
17
16
15
14
13
Ref OSC
Buffer
Charge
Pump
Divider
1/80, 1/200
Phase
DET
Prescaler
1/32
OSC
Divider
10bit+4bit
Phase
Shifter
Comparator
DC AMP
LPF
QMIX
Buffer
DC AMP
LPF
IMIX
Buffer
QOUT
XCONT
IOUT
IQGND
GND
7
8
9
10
11
12
NSET
6
RFVCC
5
RFIN1
4
RFIN2
3
AGC
2
RFGND
1
IQVCC
AGC
AMP
—2—
CXA3038N
Pin Description
Pin
No.
Symbol
Typical pin
voltage
1
IQVCC
5V
Equivalent circuit
Description
IQ output circuit VCC.
1
20
2
QOUT
2
2.7 V
Q output.
5
21
3
XCONT
Open or 5 V
when using
4 MHz crystal ;
0 V when using
10 MHz crystal.
Switching pin for reference divider
frequency-division ratio.
This is set to 80 frequency
divisions when open or connected
to VCC; 200 frequency divisions
when connected to GND.
10k
90k
3
20
1
20
4
IOUT
4
2.7 V
I output.
5
5
IQGND
0V
IQ output circuit GND.
6
GND
0V
GND.
7
RFGND
0V
RF circuit (AGCAmp, MIXER)
GND.
11
8
AGC
0 to 4 V
20k
AGCAmp gain adjustment.
8
20k
7
—3—
CXA3038N
Pin
No.
Symbol
Typical pin
voltage
9
RFIN2
2.1 V
Equivalent circuit
Description
9
10
5k
10
RFIN1
2.1 V
RF signal inputs.
5k
2.2V
7
11
RFVCC
RF circuit (AGCAmp, MIXER,
OSC) VCC.
5V
21
12
NSET
1.6 V
OSC frequency fine-adjustment.
The oscillator frequency based at
479.5 MHz is adjustable in ±4
steps of 50 kHz by applying a
voltage of 0 to 5 V.
12
20
14
13
LOOUT
4V
Output for OSC frequency signal
divided into 32 frequency divisions.
13
8k
20
14
PSVCC
VCC for 32 frequency division
circuit. This is set to open when
activating the built-in PLL.
5V
11
15
OSC2
700
3.7 V
700
16
3p
15
3p
16
OSC1
OSC pins.
These pins connect the varicap
diode and coil resonance circuit.
3.7 V
17
17
OSCGND
OSC circuit and phase shifter
circuit GND.
0V
—4—
CXA3038N
Pin
No.
Symbol
Typical pin
voltage
Equivalent circuit
Description
21
10k
100
18
VC
0.3 V to 5 V
Voltage output for varicap diode
making up the VCO.
18
20
21
100
19
LPF
1.8 V to 3.7 V
Phase comparison output.
This pin connects the loop filter.
19
20
20
21
DGND
DVCC
0V
5V
PLL circuit GND.
PLL circuit VCC.
21
22
REFOUT
4.1 V
REFOSC output.
22
20
21
23
LOCK
0.01 V when
unlocked; 3.2 V
when locked
PLL lock/unlock monitor.
23
200k
20
21
60k
20p
24
XTAL
4.4 V
20p
Crystal connection.
24
20
—5—
CXA3038N
Electrical Characteristics
Circuit current
Item
(Ta=25 °C, VCC=5 V, see the Electrical Characteristics Measurement Circuit.)
Symbol
Circuit current A
ICCA
Circuit current D
ICCD
Circuit current L
ICCPS
AC Characteristics
Measurement conditions
Analog circuit current at no signal.
Total current of IQVCC and RFVCC.
PLL circuit current. DVCC current.
32-frequency division circuit current at no
signal. PSVCC current.
Symbol
Measurement conditions
Iout=10 MHz, 1 Vp-p
VIN
GAGC Iout=10 MHz, 1 Vp-p, AGC=4 V-0 V
RF=–50 dBm, Iout=10 MHz, AGC=4 V
Conversion gain
CG
(Full gain)
RF=–50 dBm, Iout=10 MHz, 1 Vp-p
IQ phase error
BP
RF=–50 dBm, Iout=10 MHz, 1 Vp-p
IQ amplitude error
BV
Phase frequency error
∆fBP RF=–50 dBm, Iout=0 MHz–15 MHz, 1 Vp-p
Amplitude frequency error ∆fBV RF=–50 dBm, Iout=0 MHz–15 MHz, 1 Vp-p
RF=–50 dBm, Iout=From 1 Vp-p to 3 dB down
Cut-off frequency
fC
RF=–30 dBm, Qout=10 MHz, AGC=4 V
VQMAX
Maximum Q output
(Full gain)
RF=–30 dBm, Iout=10 MHz, AGC=4 V
VIMAX
Maximum I output
(Full gain)
NF
Iout=10 MHz, AGC=4 V (Full gain), DSB
Noise figure
RF1=489.5 MHz, RF2=490.5 MHz,
Third-order
IM3
Iout=1 Vp-p
intermodulation distortion
RF=–50 dBm, Iout=10 MHz, 1Vp-p,
Local oscillation
CN
10 kHz offset
phase noise
RF=–50 dBm, Iout=10 MHz, 1Vp-p,
refLK
PLL reference leak
50 kHz S/I
RF input admittance
Typ.
Max.
Unit
41
60
80
mA
2
3.5
5.5
mA
1.1
1.6
2.4
mA
(Ta=25 °C, VCC=5 V, see the Electrical Characteristics Measurement Circuit.)
Item
Input sensitivity
Gain control range
RF pin local
oscillation leak
QOUT pin local
oscillation leak
IOUT pin local
oscillation leak
REFout pin local
oscillation leak
Min.
Min.
Max.
32.5
Typ.
–50
35
—
Unit
dBm
dB
52
54
57
dB
±4
±0.5
±0.5
±0.1
deg
dB
deg
dB
MHz
25
2.5
3
3.5
Vp-p
2.5
3
3.5
Vp-p
9
dB
32
dB
–88
dBc/Hz
–81
dB
dBm
RFLK
AGC=4 V, f=479.5 MHz
–21
QLK1
QLK2
ILK1
ILK2
AGC=4 V, f=479.5 MHz
AGC=0 V, f=479.5 MHz
AGC=4 V, f=479.5 MHz
AGC=0 V, f=479.5 MHz
–34
–40
–34
–40
REFLK f=479.5 MHz
rπ
Cπ
f=479.5 MHz, AGC=4 V (Full gain)
Measured value for untuned inputs.
Noise figure is the direct reading value from the NF meter.
—6—
dBm
dBm
–34
dBm
1.25 k
1.4
Ω
pF
CXA3038N
PLL Block
(Ta=25 °C, VCC=5 V, see the Electrical Characteristics Measurement Circuit.)
Item
Symbol
Measurement conditions
LPF (charge pump)
H output current
ILPFH
L output current
ILPFL
VC
Output voltage range
VVCH XCONT=OPEN, PLL lock
LOCK
H output voltage
VLH XTAL=4 MHz, XCONT=OPEN, PLL lock
XTAL=4 MHz, XCONT=GND, PLL unlock
L output voltage
VLL
REFOUT
Output frequency
fREF XTAL=4 MHz
Output amplitude
VREF XTAL=4 MHz
LOOUT
(32 frequency divisions)
OSC=479.5 MHz during PLL lock
Output frequency
fLO
Output amplitude
VLO OSC=479.5 MHz during PLL lock
OSC control
479.7 MHz control voltage
f+4
NSET=0 V, f0 V–f0=f∆4
479.65 MHz control voltage f+3
NSET=0.4 V, f0.4 V–f0=f∆3
479.6 MHz control voltage
f+2
NSET=0.8 V, f0.8 V–f0=f∆2
479.55 MHz control voltage f+1
NSET=1.2 V, f1.2 V–f0=f∆1
479.5 MHz control voltage
f0
NSET=1.6 V
479.45 MHz control voltage f–1
NSET=2.0 V, f2.0 V–f0=f∆–1
479.4 MHz control voltage
f–2
NSET=2.4 V, f2.4 V–f0=f∆–2
479.35 MHz control voltage f–3
NSET=2.6 V, f2.6 V–f0=f∆–3
479.3 MHz control voltage
f–4
NSET=3.2 V, f3.2 V–f0=f∆–4
—7—
Min.
Typ.
Max.
–50
50
0.3
2.8
0
3.2
0.01
230
4.000
280
300
14.9844
380
0.597 VCC
0.517 VCC
0.438 VCC
0.358 VCC
0.279 VCC
0.199 VCC
0.120 VCC
0.042 VCC
0
Unit
µA
µA
VCC
V
4.2
0.2
V
V
400
MHz
mVp-p
500
MHz
mVp-p
VCC
0.590 VCC
0.515 VCC
0.436 VCC
0.356 VCC
0.277 VCC
0.197 VCC
0.118 VCC
0.04 VCC
V
V
V
V
V
V
V
V
V
1n
1n
QOUT
2
1
3
IOUT
4
5
GND
7
XTAL XCONT
4MHz 5V/OPEN
10MHz GND
6
RFGND
CXA3038N
8
9
1n
11
10
13
14
15
16
17
18
1n
19
1n
1T362
20
1n
80nH
L
21
51k
LOOUT
22
10n 4MHz
XTAL
IQVCC
LOCK
2p
REFOUT
QOUT
DVCC
XCONT
DGND
IOUT
LPF
IQGND
VC
23
13k
OSCGND
AGC
OSC1
RFIN2
24
10n
680n
150n
1n
OSC2
RFIN1
PSVCC
100k
12
NSET
LOOUT
RFVCC
—8—
VCC (+5V)
AGC
XTAL
10µ
5p
1n
1n
REFOUT
51k
L: Inductance constant
Wire
Winding Number
diameter diameter of turns
0.5
3.0
2.5
LOCK
1n
10n
Electrical Characteristics Measurement Circuit
1n
RF IN
DVCC (+5V)
PSVCC (+5V)
VC
CXA3038N
VCC (+5V)
10µ
1n
80nH
L
1T362
3
IOUT
4
5
6
7
AGC
9
8
10
68k
12
11
Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for
any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same.
QOUT
2
1
GND
CXA3038N
13
14
15
16
17
18
19
20
1n
L ; 0.5/3.0/2.5T
51k
21
RFGND
XTAL
1n
22
10n 4MHz
XTAL
IQVCC
LOCK
2p
REFOUT
QOUT
DVCC
XCONT
DGND
IOUT
LPF
IQGND
VC
23
13k
OSCGND
AGC
OSC1
RFIN2
OSC2
RFIN1
PSVCC
24
10n
680n
150n
1n
5p
1n
1n
Reference Clock for
Tuner stage PLL.
1n
1n
REFOUT
51k
1n
LOOUT
RFVCC
—9—
NSET
Application Circuit
RF IN
479.5MHz
from Tuner stage
33k
CXA3038N
CXA3038N
Description of Operation
(See the Electrical Characteristics Measurement Circuit.)
Oscillator circuit
• This is a differential amplification-type oscillator circuit, and it is oscillated by connecting an LC parallel
resonance circuit via a coupling capacitance between Pin 15 and Pin 16.
A varicap diode is used as a capacitor for the LC parallel resonance circuit to configure the VCO. Set the L
value so that the OSC oscillation frequency is approximately 480 MHz when a voltage of 2.5 V is applied to
the varicap diode.
• The oscillator signal is injected into the phase shifter circuit.
Phase shifter circuit
• This is a phase shifter having CR configuration.
This circuit produces two local signals having a 90° phase difference at 479.5 MHz and injects these signals
to the IQ mixer circuit.
AGC amplifier circuit
• An IF signal (480 MHz band) from the tuner stage is input to Pins 9 and 10.
This IF signal which is input to Pins 9 and 10 is amplified by the AGC amplifier and injected into the IQ mixer
circuit.
• The gain can be adjusted by applying the AGC voltage to Pin 8.
The applied AGC voltage ranges from 0 to 4 V, with the minimum gain at 0 V and the maximum gain at 4 V.
IQ mixer circuit
• This is a double-balance mixer-type circuit consisting of two mixer circuits.
• The IF signal amplified by the AGC amplifier is converted into a base band signal by the local signal.
Low-pass filter circuit
• This is a low-pass filter with a CR configuration.
• The cut-off frequency is set at 25 MHz (–3 dB point).
Output amplifier circuit
• The signal is converted to a base band signal by the I and Q mixer circuits, and the high-frequency
component is removed by the low-pass filter. This signal is then amplified by the output amplifier circuit and
output to Pin 2 as a Q signal. In the same way, the I signal is output to Pin 4.
• The output is low impedance.
—10—
CXA3038N
PLL circuit (when Pin 21 is connected to VCC)
• A PLL is formed by connecting the anode of the LC parallel resonance circuit varicap diode to the Pin 18
output via a high resistance of approximately 10 kΩ and connecting a loop filter between Pin 18 and Pin 19.
• The PLL circuit consists of a main divider, reference divider, phase comparator, charge pump, and reference
oscillator.
• The frequency dividing data is included in the main divider, making external data settings unnecessary.
• The reference frequency has been designed at 50 kHz.
• Fine adjustment of the VCO frequency can be performed by changing the frequency dividing value of the
main divider through an applied voltage to Pin 12. This allows adjustment in ±4 steps at 50 kHz intervals
based at 479.5 MHz as shown in the table below.
Pin 12 voltage [V]
0.597 VCC or more
0.517VCC to 0.595VCC
0.438VCC to 0.515VCC
0.358VCC to 0.436VCC
0.279VCC to 0.356VCC
0.199VCC to 0.277VCC
0.120VCC to 0.197VCC
0.042VCC to 0.118VCC
0 to 0.04VCC
Frequency dividing value
9594
9593
9592
9591
9590
9589
9588
9587
9586
VCO oscillation frequency [MHz]
479.70
479.65
479.60
479.55
479.50
479.45
479.40
479.35
479.30
• The reference divider has two types of frequency dividing data, 80 and 200.
• Either 4 MHz or 10 MHz can be selected for the crystal oscillator. When using the 4 MHz crystal oscillator,
opening Pin 3 will select a frequency dividing value of 80 for the reference divider, and the reference
frequency will become 50 kHz.
In the same way, when using the 10 MHz crystal oscillator, connecting Pin 3 to GND will select a frequency
dividing value of 200 for the reference divider, and the reference frequency will become 50 kHz.
This is summarized in the table below.
Crystal
oscillator
4 MHz
10 MHz
Frequency dividing value
of the reference divider
Open
80
0.8 V or less
200
Pin 3 voltage
—11—
Reference frequency
50 kHz
50 kHz
CXA3038N
Reference oscillator circuit
• This is oscillated by connecting a crystal oscillator (4 MHz or 10 MHz) between Pin 24 and GND.
• The input capacitance of Pin 24 is approximately 14 pF. Therefore, a crystal with a load capacitance of 12
pF is recommended. When connecting a crystal with a large load capacitance of 16 pF or so, connect a low
capacitance between Pin 24 and GND as shown in the figure below, and adjust the frequency.
24
Reference frequency
fine-adjustment capacitance
Capacitance of DC
components eliminated
Crystal oscillator
4MHz or 10MHz
• The reference oscillator signal is sent to the reference buffer circuit and output from Pin 22 by the emitter
follower. The reference oscillator signal becomes the PLL comparison frequency in the IC.
• The output amplitude is approximately 300 mVp-p.
200µA
24
22
Usage as PLL reference frequency for the tuner block
Charge pump circuit
DVCC
1k
1k
10k
19
From phase divider
100
18
From main divider
DGND
50µA
1k
500
100
20k
• The output current of the charge pump has been designed at 50 µA.
• The Pin 18 output voltage ranges from approximately 0.3 V to VCC.
• In the loop filter example for the Electrical Characteristics Measurement Circuit, the lockup time is
approximately 25 ms.
—12—
CXA3038N
32 frequency division circuit (when Pin 14 is connected to VCC)
• An oscillation signal is sent from the oscillator circuit to the 32 frequency division circuit via a coupling
capacitance. The 32 frequency division signal is output from Pin 13 by the counter.
• The output is approximately 400 mVp-p ECL output.
Notes on Operation
• These circuits use high-frequency processes, and the electrostatic strength is weak.
Therefore, please be careful of surges and other excessive input.
• The IQ error may vary depending on the connection locations of the GND pattern and VCC-GND bypass
capacitors, oscillation amplitude of the oscillator circuit, and other factors.
—13—
CXA3038N
RF input level vs. Amplitude error
IQ output frequency=1MHz, QOUT=1Vp-p
RF input level vs. Phase difference
IQ output frequency=1MHz, QOUT=1Vp-p
95
2
94
1.5
1
92
Amplitude error [dB]
Phase difference [deg]
93
91
90
89
88
0.5
0
–0.5
–1
87
–1.5
86
–2
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10
85
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10
RF input level [dBm]
RF input level [dBm]
IQ output frequency vs. Phase difference
RF input level=–40dBm, QOUT=1Vp-p
IQ output frequency vs. Amplitude error
RF input level=–40dBm, QOUT=1Vp-p
2
95
94
1.5
1
92
Amplitude error [dB]
Phase difference [deg]
93
91
90
89
88
0.5
0
–0.5
–1
87
–1.5
86
85
0
2
4
6
8
10
12 14
16
18
–2
20
2
4
6
8
10
12
14
16
18
IQ output frequency [MHz]
Supply voltage vs. Current consumption
During PLL operation
Noise figure characteristics
RF input level=–40dBm, QOUT=10MHz
20
35
90
30
80
25
70
NF [dB]
Current consumption [mA]
0
IQ output frequency [MHz]
60
20
15
50
10
40
30
4.2
5
4.4
4.6
4.8
5
5.2
5.4
5.6
0
0
5.8
Supply voltage [V]
0.5
1
1.5
2
2.5
3
3.5
AGC voltage [V]
—14—
4
4.5
5
CXA3038N
AGC voltage vs. Gain
RF input level=–40dBm, IQ output frequency=1MHz
60
Third-order intermodulation distortion characteristics
20
55
10
50
Fundamental
0
QOUT output level [dBm]
Gain [dB]
45
40
35
30
25
–10
–20
–30
–40
20
–50
15
10
0
1
2
3
AGC voltage [V]
RF input level [dBm]
Phase noise characteristics
RF input level=–40dBm, QOUT=1 MHz, 1Vp-p
–50
–60
C/N [dBc/Hz]
–70
–80
–90
–100
–110
–120
0.1
1
10
OSC=479.5MHz
RF1=498.5MHz
RF2=490.5MHz
AGC=4V
–60
–100 –90 –80 –70 –60 –50 –40 –30 –20 –10
5
4
AAAA
AAAA
AAAA
Third-order intermodulation
distortion component
100
1000
Offset frequency [kHz]
—15—
0
CXA3038N
Package Outline
Unit : mm
24PIN SSOP(PLASTIC)
+ 0.2
1.25 – 0.1
∗7.8 ± 0.1
24
0.1
13
∗5.6 ± 0.1
7.6 ± 0.2
A
1
+ 0.1
0.22 – 0.05
12
+ 0.05
0.15 – 0.02
0.13 M
0.65
0.5 ± 0.2
0.1 ± 0.1
0° to 10°
NOTE: Dimensions “∗” does not include mold protrusion.
DETAIL A
PACKAGE STRUCTURE
PACKAGE MATERIAL
EPOXY RESIN
SONY CODE
SSOP-24P-L01
LEAD TREATMENT
SOLDER/PALLADIUM
PLATING
EIAJ CODE
SSOP024-P-0056
LEAD MATERIAL
42/COPPER ALLOY
PACKAGE MASS
0.1g
JEDEC CODE
NOTE : PALLADIUM PLATING
This product uses S-PdPPF (Sony Spec.-Palladium Pre-Plated Lead Frame).
—16—