View CXA1741Q_327292.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

CXA1741Q
IF Amplifier for Analog Cellular Communications
Description The CXA1741Q is an analog cellular(TACS/ NTACS) FM IF IC which incorporates an IF filter. Features * Incorporates a ceramic filter function, which is normally mounted externally. * Quadrature detection discriminator function. * This IC has almost all IF functions and is ideal for reduction in set size because of few external parts required. * The built-in filter permits mode changeover between TACS and NTACS. * Wide operating voltage range (2.7 V to 3.6 V) and low current consumption (Icc=10 mA (typ.) when Vcc= 3 V). * Wide range and excellent temperature characteristics for the RSSI (receiving signal strength indicator). Applications Ideally suited for cellular phones, particularly handheld sets. Structure Bipolar silicon monolithic IC 40 pin QFP (Plastic)
Absolute Maximum Ratings (Ta = 25C) * Supply voltage VCC 5 V * Operating temperature Topr -35 to +85 C * Storage temperature Tstg -65 to +150 C * Allowable power dissipation PD 500 mW Operating Conditions Supply voltage
VCC
2.7 to 3.6
V
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--
E94245-TE
CXA1741Q
Block Diagram and Pin Configuration (Top View)
MIXADJ1
MIXADJ2
MIXPS
MIXIN
IFPS
GND
30 T4 31
29
28
27
26
25
24
VCC
23
22
IFIN
T3
21 20 XTALIN
PSN T5 32 PSN VCC1 33 MIXER
RF AMP 19 XTALOUT
GND
18 AGCPS 17 VREF 16 RSSIPS 15 T2 14 RSDETPS 13 T1 12 GND2 11 VCC2 10
GND1 34 BPF0 T6 35
1/2
OSC
AGC FADJ1 36 FADJ2 37
BPF1 RSSI
SGND 38
BIAS LIM DET
BPFPS1 39
BPFPS2 40
1
SW(TACS/NTACS)
2
NC
3
BPFO
4
5
6
AUDIO
7
RSSI
8
GADJ(RSSI)
9
IF2
Note) Pins 21 and 25 are connected via the IC internal wiring. Pins 12, 21 and Pins 25, 34 are connected via IC internal resistors. When designing a PCB, ensure that all GND pins of IC are connected to the GND on PCB with its connection wiring distance minimized.
--2--
LIMPS
CXA1741Q
Pin No. 1
Symbol SW TACS NTACS
Pin voltage DC AC 0V OPEN HIGH (3 V)
I/O resistance
31
Equivalent circuit
Description Changeover switch for built-in filter. TACS for Low; NTACS for High.
(
)
20A
50k 1 50k
VREF GND
34
2 3 4 5
NC BPFO
1.8 V
Not internally connected. BPF output monitor. Not used normally. Connected to the LIM and RSSI inputs in the IC.
33
147
3 4 5
34
B.P.F N.F.B Network
LIM
RSSI
6
AUDIO
2.1 V
11
Outputs an AUDIO signal which is FM-detected.
1k
6
12
--3--
CXA1741Q
Pin No. 7
Symbol RSSI
Pin voltage DC AC 1.2 V
I/O resistance
Equivalent circuit
Description RSSI output. Outputs a DC voltage in accordance with the signal input to the RF amplifier.
11
147
7
12
8
GADJ
0.2 V
Adjusts the RSSI amplifier gain (varies the resistance so as to obtain a linear RSSI output).
147
8
147
7
9
IF2
0.9 V
11
Limiter operation monitor. Not used normally.
147
9
12
10
LIMPS
1.8 V
11
Connects a limiter integrating capacitor.
10
12
--4--
CXA1741Q
Pin No. 11
Symbol VCC2
Pin voltage DC AC 3.0 V
I/O resistance
Equivalent circuit
Description Power supply. Supplies current to the LIM, DET, and RSSI circuits. Ground. IC operation check. Connects an RSSI detector integrating capacitor.
12 13 14
GND2 T1
0V
RSDETPS 1.4 V
11
147 14
12
15 16
T2 RSSIPS 1.8 V
11
IC operation check. Connects an RSSI integrating capacitor.
16
12
17
VREF
1.3 V
33 17
34 reference voltage used in the internal circuit
Monitor for the reference voltage used in the internal circuit. When connected to an external capacitor, this pin also functions to lower the reference voltage dynamic impedance.
--5--
CXA1741Q
Pin No. 18
Symbol AGCPS
Pin voltage DC AC 0.2 V
I/O resistance
Equivalent circuit
Description Connects an AGC integrating capacitor.
33
18 VREF
34 15
19
XTALOUT 2.9 V
24 147 20 10k 15p 10k 19
20
XTALIN
2.9 V
Connect a crystal oscillator to form a Colpitts-type oscillator circuit. When an external oscillator is used, its input must be connected to Pin 20.
25
21
21 22
GND IFIN
0V 1.3 V
24
23
IFPS
1.3 V
22 1.5k 1.5k
23
VREF 21 25
Ground. RF amplifier input. The relationship between IFIN (Pin 22) and IFPS (Pin 23) is designed so that the IC internal stray capacitance is small. Therefore, if Pins 22 and 23 are used for balance input, the common-mode rejection deteriorates. Power supply. Supplies current to the RF AMP, MIXER, OSC, and 1/2 DIVIDER circuits. Ground.
24
VCC
3.0 V
25
GND
0V
--6--
CXA1741Q
Pin No. 26
Symbol MIXIN
Pin voltage DC AC 1.3 V
I/O resistance
Equivalent circuit
Description RF AMP output monitor. Connected to the MIXER input in the IC.
27
27
MIXPS
1.3 V
26 MIXER RF AMP
28
MIX ADJ2 0.1 V
Balance adjustment for mixers 1 and 2.
29
MIX ADJ1 0.1 V
4k
4k 28 29
4k
4k
660
660
30 31 32 33
T3 T4 T5 VCC1
IC operational check.
3.0 V
34 35 36
GND1 T6 FADJ1
0V
Power supply. Supplies current to the PSN, BPF, and BIAS circuits. Ground. IC operational check. When the resistance value of an external resistor connected between Pins 36 and 37 is varied, the center frequency of the BPF in the IC changes accordingly.
2.2 V
147 36
37
FADJ2
1.5 V
37
147
--7--
CXA1741Q
Pin No. 38
Symbol SGND
Pin voltage DC AC 1.8 V
I/O resistance
Equivalent circuit
33
Description Monitor for the pseudground voltage used in the internal circuits. When connected to an external capacitor, this pin also functions to lower the reference voltage dynamic impedance.
38
34 B.P.F signal reference voltage
39
BPFPS1
1.1 V
33
39
40
BPFPS2
1.2 V
40 34 reference voltage used for B.P.F
Monitor for the reference voltage used by the BPF. When connected to an external capacitor, these pins also function to lower the reference voltage dynamic impedance.
--8--
CXA1741Q
Electrical Characteristics
0dBm = 50, 1mW VCC = 3V, Ta = 25C FOSC = 89.9 MHz Conditions fin = 45 MHz, -30 dBm Pin 11 fin = 45 MHz, -30 dBm Pin 24 fin = 45 MHz, -30 dBm Pin 33 0V 3V Crystal osc. 89.9 MHz 1.2 1.6 1 1 Crystal osc. 89.9 MHz 70 Min. 0.8 2 3.8 -14 15 Typ. 1.1 2.9 5.3 -10 23 0.4 1.25 1.8 1.17 1.2 93 Max. 1.5 3.8 7 -7 30 0.6 1.3 2 1.4 1.4 130 Unit mA mA mA A A mA V V V V mV rms
Item
Symbol
Current consumption - 1 ICC-11 Current consumption - 2 ICC-24 Current consumption - 3 ICC-33 Pin current Pin 1 - Low Pin current Pin 1 - High Pin current Pin 19 Pin voltage - Pin 17 Pin voltage - Pin 38 Pin voltage - Pin 39 Pin voltage - Pin 40 OSC output swing Pin 19 IIL IIH I19 V17 V38 V39 V40 VOSC
Wide BPF; TACS mode (Pin 1=Low) BPF output voltage - 1 BPF output voltage - 2 IF1 output voltage Mixer image rejection level BPF 6 dB bandwidth BPF 40 dB bandwidth BPF extraband attenuation FM detection level AM rejection ratio VTG1 VTG2 VTIF VIMAG BW6dB fin = 45 MHz, -50 dBm fin = 45 MHz, -20 dBm fin = 45 MHz, -20 dBm fin = 44.9 MHz, -30 dBm 100 220 80 162 291 89 30 26 47 56 150 194 -27 250 -20 220 360 100 100 30 mV rms mV rms mV rms mV rms kHz kHz dB mV rms dB
Vin = -50 dBm, Swept with fin = 45 MHz regarded as the center Vin = -50 dBm, Swept with fin = 45 MHz BW40dB regarded as the center ATT40K FMDET AMR fo 40 kHz fin = 45 MHz, -30 dBm, fmod=1 kHz, Dev. = 5.6 kHz, Dev. = 5.6 kHz, used LPF 20 kHz fin = 45 MHz, -30 dBm, fmod = 1 kHz, Mod = 80% used LPF 20 kHz --9--
CXA1741Q
Item Audio output distortion RSSI output voltage - 11 RSSI output voltage - 12 RSSI output voltage - 13
Symbol THD
Conditions fin = 45 MHz, -30 dBm, fmod = 1 kHz, Dev. = 8 kHz, used LPF 20 kHz
Min.
Typ. 3.7
Max. 6 1.3 2.2 2.8
Unit % V V V
RSSI11 No input RSSI12 fin = 45 MHz, -60 dBm RSSI13 fin = 45 MHz, -20 dBm
1 1.65 2.4
1.15 1.93 2.67
Narrow BPF; NTACS mode (Pin 1=High) Mixer 3rd inter-modulation BPF 6 dB bandwidth BPF 40 dB bandwidth BPF extraband attenuation FM detection level AM detection level Audio output distortion RSSI output voltage - 21 RSSI output voltage - 22 RSSI output voltage - 23 Others Equivalent input resistance Pin 22 Equivalent input capacitance Pin 22 BPF*fo temperature characteristics TACS mode BPF*fo temperature characteristics NTACS mode RIN CIN f = 55 MHz f = 55 MHz 1.4 4.7 k pF f1 = 45.02 MHz, -30 dBm, f2 = 45.04 MHz, -30 dBm Vin = -50 dBm, Swept with fin = 45 MHz BW6dB regarded as the center Vin = -50 dBm, Swept with fin = 45 MHz BW40dB regarded as the center IM3 ATT20K fo 20 kHz FMNDET AMRN THDN fin = 45 Mhz, -30 dBm, fmod = 1 kHz, Dev. = 3 kHz, Used LPF 20 kHz fin = 45 Mhz, -30 dBm, fmod = 1 kHz, Mod = 80%, Used LPF 20 kHz fin = 45 Mhz, -30 dBm, fmod = 1 kHz, Dev. = 3 kHz, Used LPF 20 kHz 4.5 13.5 23 62 99 16 2.8 1.09 1.91 2.65 20 16 mV rms kHz kHz dB mV rms dB % V V V
RSSI21 No input RSSI22 f = 45 MHz, -60 dBm RSSI23 f = 45 MHz, -20 dBm
Ta = -30 to + 70C
1.5
kHz
Ta = -30 to + 70C
1.5
kHz
--10--
CXA1741Q
Measurement Circuit
6
100
103
S6
500 10p
6p
PSN 32 PSN 33 104 MIXER
RF AMP 19 0.47 102 18 104
34 BPF0 35
1/ 2 AGC
OSC
17 223 16 S4
56K 36 BPF1 37 VR10K 104 38 BIAS LIM 39 104 40 104 11 DET 12 13 RSSI 14 15
104 1k S3 5
1
S1
2
3
4
5
6
7
102
8
47k
9
S2
10
220k
1
2
3
4
--11--
1k
103
104
102
31
20
89.9MHz
30
29
28
27
26
25
24
23
101
22
1.5
104
Vcc 3V 7
10
S5
104
47
21
CXA1741Q
Application Circuit
45MHz IN Oscillator circuit
Vcc
7p 1.5
0.1
0.1 30 31 PSN 0.1 32 PSN Vcc 33 MIXER RF AMP 29 28 27 26 25 24 23 22
100p 10p 20
109.9MHz 21
0.33
Vcc 19
18
0.047
34 BPF0 35
1/2
OSC
17
0.1
16 AGC
0.1
20k 36 BPF1 51k 37 RSSI 14 0.1 15
2.2
38
BIAS LIM DET
13
39 2.2 40 2.2
12
11
Vcc 0.1
1
2
3
4
5
94k 82p
6
7
220k 47k
8
9
10
0.1
TACS 50K
NTACS 50K AUDIO OUT Vcc RSSI OUT
Note: Use a 0.1F capacitor for Pin 14 decoupling. The IC malfunctions at a capacitance of 0.047F or lower. The oscillator circuit must be changed according to the crystal characteristics. When designing PCB pattern, make PCB pattern so that Pins 3, 4, and 5 are connected correlatively. This makes IC other than TACS/NTACS standard possible to use without changing PCB pattern.
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.
--12--
CXA1741Q
Description of Operation A 45 MHz IF signal is input to Pin 22. This input signal is amplified at the RF AMP and then mixed with the local oscillation signals from the oscillator at the mixer to change the signal frequency to 50 kHz. When a crystal resonator or like external circuit is connected to Pins 19 and 20, the oscillator can be self-executed by composing a Colpitts-type oscillation circuit. It can be also used with an external local oscillation signal applied to Pin 20. The internal BPF eliminates any interference from the converted 50 kHz signal, which is then fed to the limiter and RSSI circuit. The limiter eliminates an amplitude component from the signal. The resulting signal is then detected at the quadrature FM detector circuit, and Pin 6 outputs an audio signal. The RSSI circuit detects the RF AMP input signal voltage and generates from Pin 7 the DC voltage where the detected voltage value is logarithmically compressed. SW (Pin 1) can switch the NTACS and TACS modes.
45MHz IN
IFIN 30 31 PSN 32 PSN 33 MIXER RF AMP 29 28 27 26 25 24 23 22 21 20 XTALIN Crystal Oscillator Circuit
19 XTALOUT
18
34 BPF0 35
1/2
OSC
17
16 AGC
36 BPF1 37 RSSI
15
14
38
BIAS LIM DET
13
39
12
40
11
1
2
3
4
5
6
7
RSSI OUT
8
9
10
TACS
NTACS
AUDIO OUT
Vcc
AUDIO RSSI output output
Signal Flow
--13--
CXA1741Q
1) Power supply Power supply pins (Pins 11, 24, and 33) must be decoupled with the shortest distance. 2) Oscillator The figures below show how to use the CXA1741Q oscillator.
Vcc
Vcc
Vcc C2
20
20 600mVp-p or more Crystal 19 C1 L
19
Vcc
(a) Inputting a local oscillation signal from an external circuit. The circuit current varies with the externally fed signal amplitude. The reason is that the AGC circuit, which works to maintain the oscillation amplitude constant when a Colpitts-type oscillator circuit is formed, also operates when an external local oscillation signal is input.
(b) Configuring a Colpitts-type oscillator circuit. The C1, C2, and L must be changed according to the crystal characteristics. The oscillation Tr in the IC is internally subjected to AGC so that the oscillation level at Pin 19 is not likely to be affected by temperature or supply voltage fluctuations.
3) Mixers Since the BPF in the IC has an fo value as low as 50 kHz, the IC employs an image rejection type of mixer having an enhanced interference elimination capability. Therefore, the two internal mixers must be accurately adjusted so that their gains are equal. Normally, an adequate degree of image rejection is provided without using Pins 28 and 29. However, when they are used for adjustment purposes, an increased degree of image rejection will result.
500 29 28
--14--
CXA1741Q
4) BPF The passband frequency of the built-in filter should be adjusted. For adjustment method, adjust skirt characteristics of band-pass filter to be symmetric with respect to the center frequency. Or observe the AUDIO output at Pin 7 and adjust the variable resistor between Pins 36 and 37 so as to minimize the AUDIO output distortion.
36
37
5) RSSI (receiving signal strength indicator) RSSI detects the input signal level. The IC generates a DC voltage output, which is nearly proportional to the logarithmic value of RF input level. The output level can be varied by adjusting GADJ (Pin 8) resistance value. Adjust the resistance value so that saturation does not occur when the input level is high.
V
Vcc (approx. 0.5V)
Adjust for this curve.
RSSI
7
8
RSSI 0 Input level dBm
--15--
CXA1741Q
Notes on Operation 1. This IC must be handled with care because it is extremely susceptible to electrostatic surges. Particularly, IFIN (Pin 22) is easily affected by electrostatic surges. 2. When the 0.1F capacitor connected to Pin 14 has a capacitance of 0.047F or less, the IC malfunctions. Be sure that the employed capacitor has an excellent temperature characteristics. 3. When the capacitance value of the 0.1F capacitor connected to Pin 38 is decreased, the IC characteristics begin to slightly deteriorate. Further, a capacitance value increase would not improve the IC characteristics accordingly. 4. When the capacitance value of the 0.1F capacitor connected to Pin 40 is decreased, the IC characteristics slightly deteriorate. 5. Vcc1 (Pin 33) supplies the power to the reference bias voltage generator circuit which is necessary for IC operations. If the same VCC power supply is not provided for Vcc voltages to be applied to Pins 11, 19, 24, and 33, ensure that the Pin 33 Vcc rises first. 6. Be sure that nothing is connected to Pins 13, 15, 30, 31, 32, and 35. 7. Resistance between Pins 36 and 37 The signal of 45 MHz, -50 dBm is input from Pin 22 (IFIN) and the level of Pin 3 (BPFOUT) is read. After that when this frequency is varied to +8 kHz and -8 kHz respectively, resistance value between Pins 36 and 37 is varied to be the same attenuation level. 8. Inductance between Pins 26 and 27 Adjustment must be made so that a 45 MHz parallel resonance circuit is formed by the inductor between Pins 26 and 27 and the IC stray capacitor. This adjustment assures that an increased mixer conversion gain is provided at a low input signal level. Once the optimum value is obtained upon PCB conductive pattern determination, readjustment is unnecessary after sample changes. 9. Pin 19 resonance circuit This circuit must be adjusted for the crystal oscillation frequency. Once the optimum value is obtained upon PCB conductive pattern determination, readjustment is unnecessary after sample changes.
--16--
CXA1741Q
Example of Representative Characteristics The following characteristic curves are measured after IC adjustment. If the IC is not properly adjusted, the resulting characteristics are not close to the representative characteristics presented below. When making measurements, observe precautions 7, 8, and 9 under "Notes on Operation".
Sensitivity of adjust R vs fo 60
55
BPF*fo [kHz]
50
45
52
54
56
58
60
62
64
66
68
70
72
Total resistance value [k ]
Pass Band Shift by the BPF*fo adjustment 20
19
NTACS*BW 20dB [kHz]
18
17
16
15
14 45 50 BPF*fo [kHz] 55 60
--17--
CXA1741Q
[dB] TACS 40 NTACS
Response
30
20
CXA1741*SINAD TACS f=45MHz, FM Modulation Dev. 5.7kHz Audio 1kHz CCITT weighting NTACS f=45MHz, FM Modulation Dev. 3kHz Audio 1kH CCITT weighting Ta=25C Vcc=3.3V
10
0
-120
-100
-80
-60
-40
-20
[dBm]
Input level [dB] 0 S CXA1741*TACS CCITT weighting f=45MHz FM Modulation Dev. 5.7kHz Audio 1kHz Ta=25C VCC=3.3V
-10
-20
Response
-30
-40
D
-50
-60 -120 -100 -80 -60 -40 -20
N
[dBm]
Input level [dB] 0 S CXA1741*NTACS CCITT weighting f=45MHz FM Modulation Dev. 3kHz Audio 1kHz Ta=25C VCC=3.3V
-10
-20
Response
-30 D -40
-50 N -60 -120 -100 -80 -60 -40 -20 [dBm]
Input level
--18--
CXA1741Q
Selectivity characteristics D/U [dB] 70 60 50 40 30 20 10 TACS NTACS
VCC=2.7V Ta=25C 20dB SINAD=-96dBm
-50
-40
-30
-20
-10
+10
+20
+30
+40
+50
45MHzf [kHz] Image rejection characteristics D/U [dB] 80 NTACS 70 VCC=2.7V Ta=25C 60 50 40 30 20 10
TACS
-40 -30
-20
-10
0
+10
+20
+30
+40
44.9MHzf [kHz]
Detuning characteristics Distortion [%] 14 12 NTACS 10 8 6 4 2 TACS
TACS Deviation 5.7kHz Audio 1kHz CCITT weighting NTACS Deviation 3kHz Audio 1kHz CCITT weighting VCC=2.7V Ta=25C
-10
-8
-6
-4
-2
0
+2
+4
+6
+8
+10
45MHzf [kHz]
--19--
CXA1741Q
RSSI characteristics-1 [V] 3.0 TACS VCC=2.7V 2.5 [V] 3.0 NTACS VCC=2.7V 2.5
RSSI characteristics-2
70C 25C -30C
70C 25C -30C
RSSI output voltage
2.0
RSSI output voltage
Signal input from Pin 22 (IF IN) Voltage measurement at Pin 7 -100 -50 IF input voltage Modulation characteristics 0 dBm
2.0
1.5
1.5
1.0
1.0
0.5
0.5
0
0
-100
-50 IF input voltage
0 dBm
Distortion [dB] -20 IFIN to Audio OUT f=4.5Mhz, -40dBm Audio=1kHz CCITT weighting VCC=3.3V Ta=25C NTACS
-30
BPF output [dBV] 0 IFIN to BPF OUT F0=45MHz F1=45.02MHz F2=45.04MHz -20 Ta=25C VCC=3.3V TACS
I/O characteristics
IM3 -40 -40
-60 -50
2
4 6 Deviation [kHz]
8
10 -80 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 IF input [dB] Audio frequency response
Response [dB] +2 0 -2 -4 -6 -8 -10 -12 -14 10 100 1k Frequency [Hz] 10k 100k 0dB normalized at 1kHz TACS deviation 5.7kHz NTACS deviation 3kHz IFIN 45MHz, -40dBm Ta=25C, VCC=3.3V
NTACS TACS
--20--
CXA1741Q
Package Outline
Unit : mm
40PIN QFP (PLASTIC)
9.0 0.4 + 0.4 7.0 - 0.1 30 21
+ 0.35 1.5 - 0.15 + 0.1 0.127 - 0.05 0.1
31
20
A
40
11
1 0.65 + 0.15 0.1 - 0.1
+ 0.15 0.3 - 0.1
10 0.12 M
0.5 0.2
(8.0)
PACKAGE STRUCTURE
PACKAGE MATERIAL LEAD TREATMENT LEAD MATERIAL PACKAGE WEIGHT EPOXY RESIN SOLDER / PALLADIUM PLATING COPPER / 42 ALLOY 0.2g
DETAIL A SONY CODE EIAJ CODE JEDEC CODE QFP-40P-L01 QFP040-P-0707
--21--

▲Up To Search▲

Price & Availability of CXA1741Q

	To Download CXA1741Q Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .