參數(shù)資料
型號: TDA9811
廠商: NXP SEMICONDUCTORS
元件分類: 接收器
英文描述: Multistandard VIF-PLL with QSS-IFand AM demodulator(帶QSS-IF和AM解調(diào)器的多標(biāo)準(zhǔn)的VIF-PLL)
中文描述: AUDIO/VIDEO DEMODULATOR, PDIP32
封裝: 0.400 INCH, PLASTIC, SOT-232, SDIP-32
文件頁數(shù): 7/36頁
文件大?。?/td> 228K
代理商: TDA9811
1998 Feb 09
7
Philips Semiconductors
Product specification
Multistandard VIF-PLL with QSS-IF and
AM demodulator
TDA9811
Video buffer
For an easy adaption of the sound traps an operational
amplifier with internal feedback is used in the event of B/G
and L standard. This amplifier is featured with a high
bandwidth and 7 dB gain. The input impedance is adapted
for operating in combination with ceramic sound traps. The
output stage delivers a nominal 2 V (p-p) positive video
signal. Noise clipping is provided.
SIF amplifier and AGC
The sound IF amplifier consists of two AC-coupled
differential amplifier stages. Each differential stage
comprises a controlled feedback network provided by
emitter degeneration.
The SIF AGC detector is related to the SIF input signals
(average level of AM or FM carriers) and controls the SIF
amplifier to provide a constant SIF signal to the AM
demodulator and single reference QSS mixer. The SIF
AGC reaction time is set to ‘slow’ for nominal video
conditions. But with a decreasing VIF amplitude step the
SIF AGC is set to ‘fast’ mode controlled by the VIF-AGC
detector. In FM mode this reaction time is also set to ‘fast’
controlled by the standard switch.
Single reference QSS mixer
The single reference QSS mixer is realized by a multiplier.
The SIF amplifier output signal is fed to the single
reference QSS mixer and converted to intercarrier
frequency by the regenerated picture carrier (VCO). The
mixer output signal is fed via a high-pass for attenuation of
the video signal components to the output pin 20. With this
system a high performance hi-fi stereo sound processing
can be achieved.
AM demodulator
The AM demodulator is realized by a multiplier. The
modulated SIF amplifier output signal is multiplied in
phase with the limited (AM is removed) SIF amplifier
output signal. The demodulator output signal is fed via an
integrated low-pass filter for attenuation of the carrier
harmonics to the AF amplifier.
Internal voltage stabilizer and
1
2
V
P
-reference
The bandgap circuit internally generates a voltage of
approximately 1.25 V, independent of supply voltage and
temperature. A voltage regulator circuit, connected to this
voltage, produces a constant voltage of 3.6 V which is
used as an internal reference voltage.
For the audio output signal the constant reference voltage
cannot be used because large output signals are required.
Therefore this signal refers to half the supply voltage to
achieve a symmetrical headroom. For ripple and noise
attenuation the
1
2
V
P
voltage has to be filtered via a
low-pass filter by using an external capacitor together with
an integrated resistor (f
g
= 5 Hz). For a fast setting to
1
2
V
P
an internal start-up circuit is added.
相關(guān)PDF資料
PDF描述
TDA9812 Multistandard VIF-PLL andFM-PLL/AM demodulator(多標(biāo)準(zhǔn)的VIF-PLL 和FM-PLL/AM解調(diào)器)
TDA9812T Multistandard VIF-PLL and FM-PLL/AM demodulator
TDA9813T VIF-PLL with QSS-IF and dual FM-PLL demodulator(帶QSS-IF和雙路FM-PLL解調(diào)器的VIF-PLL)
TDA9814T Multistandard VIF-PLL with QSS-IF and dual FM-PLL/AM demodulator(帶QSS-IF和雙路FM-PLL/AM解調(diào)器的多標(biāo)準(zhǔn)VIF-PLL)
TDA9814 Multistandard VIF-PLL with QSS-IF and dual FM-PLL/AM demodulator
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TDA9812 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Multistandard VIF-PLL and FM-PLL/AM demodulator
TDA9812T 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Multistandard VIF-PLL and FM-PLL/AM demodulator
TDA9813T 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:VIF-PLL with QSS-IF and dual FM-PLL demodulator
TDA9814 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Multistandard VIF-PLL with QSS-IF and dual FM-PLL/AM demodulator
TDA9814T 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Multistandard VIF-PLL with QSS-IF and dual FM-PLL/AM demodulator