- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄372106 > SA604 (NXP Semiconductors N.V.) High performance low power FM IF system PDF資料下載
參數(shù)資料
| 型號(hào)： | SA604 |
| 廠商： | NXP Semiconductors N.V. |
| 英文描述： | High performance low power FM IF system |
| 中文描述： | IF系統(tǒng)高性能低功耗調(diào)頻 |
| 文件頁(yè)數(shù)： | 10/13頁(yè) |
| 文件大小： | 140K |
| 代理商： | SA604 |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)當(dāng)前第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)
Philips Semiconductors
Product specification
SA604A
High performance low power FM IF system
1997 Nov 07
10
Thus a small deviation gives a large output with a high Q tank.
However, as the deviation from resonance increases, the
non-linearity of the curve increases (distortion), and, with too much
deviation, the signal will be outside the quadrature region (limiting
the peak deviation which can be demodulated). If the same peak
deviation is applied to a lower Q tank, the deviation will remain in a
region of the curve which is more linear (less distortion), but creates
a smaller phase angle (smaller output amplitude). Thus the Q of the
quadrature tank must be tailored to the design. Basic equations and
an example for determining Q are shown below. This explanation
includes first-order effects only.
Frequency Discriminator Design Equations for
SA604A
V
OUT
SR00321
Figure 11.
V
O
=
C
S
C
P
+ C
S
1 +
ω
1
Q
1
S
S
+
2
(
)
1
ω
1
V
IN
(1a)
L(C
P
+ C
S
)
Q
1
= R (C
P
+ C
S
)
ω
1
where
ω
1
=
1
(1b)
(1c)
From the above equation, the phase shift between nodes 1 and 2, or
the phase across C
S
will be:
ω
1
Q
1
ω
(
1
φ
=
∠
V
O
-
∠
V
IN
=
(2)
t
g-1
ω
–
2
)
ω
1
Figure 12 is the plot of
φ
vs.
ω
ω
1
(
)
It is notable that at
ω
=
ω
1
, the phase shift is
π
2
φ
ω
The signal V
O
would have a phase shift of
2Q
1
ω
2
If V
IN
= A Sin
ω
t
V
O
= A
ω
t +
π
2
and the response is close to a straight
line with a slope of
=
ω
1
2Q
1
–
ω
1
π
with respect to the V
IN
.
Sin
(3)
ω
–
ω
1
2Q
1
Multiplying the two signals in the mixer, and
low pass filtering yields:
V
IN
V
O
= A
2
Sin
ω
t
ω
t +
π
2
after low pass filtering
Sin
(4)
ω
–
ω
1
2Q
1
Cos
(5)
ω
V
OUT
=
π
2
–
ω
1
)
ω
1
+
ω
2Q
1
1
2
A
2
=1
2A
2
Sin
ω
ω
1
ω
ω
1
(
2Q
1
(
(6)
V
OUT
∝
2Q
1
2Q
1
ω
1
=
)
For
2Q
1
ω
ω
1
<<
π
2
Which is discriminated FM output. (Note that
ω
is the deviation
frequency from the carrier
ω
1
.
Ref. Krauss, Raab, Bastian; Solid State Radio Eng.; Wiley, 1980, p.
311. Example: At 455kHz IF, with +5kHz FM deviation. The
maximum normalized frequency will be
455 +5kHz
455
= 1.010 or 0.990
Go to the f vs. normalized frequency curves (Figure 12) and draw a
vertical straight line at
ω
ω
1
= 1.01.
The curves with Q = 100, Q = 40 are not linear, but Q = 20 and less
shows better linearity for this application. Too small Q decreases
the amplitude of the discriminated FM signal. (Eq. 6)
Choose a
Q = 20
The internal R of the 604A is 40k. From Eq. 1c, and then 1b, it
results that
C
P
+ C
S
= 174pF and L = 0.7mH.
A more exact analysis including the source resistance of the
previous stage shows that there is a series and a parallel resonance
in the phase detector tank. To make the parallel and series
resonances close, and to get maximum attenuation of higher
harmonics at 455kHz IF, we have found that a C
S
= 10pF and C
P
=
164pF (commercial values of 150pF or 180pF may be practical), will
give the best results. A variable inductor which can be adjusted
around 0.7mH should be chosen and optimized for minimum
distortion. (For 10.7MHz, a value of C
S
= 1pF is recommended.)
Audio Outputs
Two audio outputs are provided. Both are PNP current-to-voltage
converters with 55k
nominal internal loads. The unmuted output
is always active to permit the use of signaling tones in systems such
as cellular radio. The other output can be muted with 70dB typical
attenuation. The two outputs have an internal 180
°
phase
difference.
The nominal frequency response of the audio outputs is 300kHz.
this response can be increased with the addition of external
resistors from the output pins to ground in parallel with the internal
55k resistors, thus lowering the output time constant. Singe the
output structure is a current-to-voltage converter (current is driven
into the resistance, creating a voltage drop), adding external parallel
resistance also has the effect of lowering the output audio amplitude
and DC level.
This technique of audio bandwidth expansion can be effective in
many applications such as SCA receivers and data transceivers.
Because the two outputs have a 180
°
phase relationship, FSK
demodulation can be accomplished by applying the two output
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| SA604A | High performance low power FM IF system |
| SA605 | HIGH PERFORMANCE LOW POWER MIXER FM IF SYSTEM |
| SA605N | HIGH PERFORMANCE LOW POWER MIXER FM IF SYSTEM |
| SA606 | RES 6.19K OHM 1/16W .5% 0603 SMD |
| SA607 | Low-voltage high performance mixer FM IF system |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| SA604A | 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:High performance low power FM IF system |
| SA604AD | 制造商:NXP Semiconductors 功能描述:FM IF System, SA604AD SOIC16 |
| SA604AD,602 | 功能描述:射頻放大器 HI PERF LP FM IF SYSTEM RoHS:否 制造商:Skyworks Solutions, Inc. 類型:Low Noise Amplifier 工作頻率:2.3 GHz to 2.8 GHz P1dB:18.5 dBm 輸出截獲點(diǎn):37.5 dBm 功率增益類型:32 dB 噪聲系數(shù):0.85 dB 工作電源電壓:5 V 電源電流:125 mA 測(cè)試頻率:2.6 GHz 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-16 封裝:Reel |
| SA604AD,623 | 功能描述:射頻放大器 HI PERF LP FM IF SYSTEM RoHS:否 制造商:Skyworks Solutions, Inc. 類型:Low Noise Amplifier 工作頻率:2.3 GHz to 2.8 GHz P1dB:18.5 dBm 輸出截獲點(diǎn):37.5 dBm 功率增益類型:32 dB 噪聲系數(shù):0.85 dB 工作電源電壓:5 V 電源電流:125 mA 測(cè)試頻率:2.6 GHz 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-16 封裝:Reel |
| SA604AD | 制造商:NXP Semiconductors 功能描述:IC FM IF SYSTEM SMD SOIC16 604 |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。