參數(shù)資料
型號(hào): TDA9806
廠商: NXP SEMICONDUCTORS
元件分類: 接收器
英文描述: Multistandard VIF-PLL and FM-PLL demodulator
中文描述: FM, VIDEO DISCRIMINATOR, PDIP32
封裝: 0.400 INCH, SHRINK, PLASTIC, SOT-232-1, DIP-32
文件頁(yè)數(shù): 7/24頁(yè)
文件大小: 193K
代理商: TDA9806
1995 Sep 05
7
Philips Semiconductors
Preliminary specification
Multistandard VIF-PLL and
FM-PLL demodulator
TDA9806
FM detector
The FM detector consists of a limiter, an FM-PLL and an
AF amplifier. The limiter provides the amplification and
limitation of the FM sound intercarrier signal before
demodulation. The result is high sensitivity and AM
suppression. The amplifier consists of 7 stages which are
internally AC-coupled in order to minimize the DC offset
and to save pins for DC decoupling.
The FM-PLL consists of an integrated relaxation oscillator,
an integrated loop filter and a phase detector. The
oscillator is locked to the FM intercarrier signal, output
from the limiter. As a result of locking, the oscillator
frequency tracks with the modulation of the input signal
and the oscillator control voltage is superimposed by the
AF voltage. The FM-PLL operates as an FM-demodulator.
The AF amplifier consists of two parts:
1.
The AF preamplifier for FM sound is an operational
amplifier with internal feedback, high gain and high
common mode rejection. The AF voltage from the PLL
demodulator, by principle a small output signal, is
amplified by approximately 33 dB. The low-pass
characteristic of the amplifier reduces the harmonics of
the intercarrier signal at the sound output terminal, at
which the de-emphasis network for FM sound is
applied. An additional DC control circuit is
implemented to keep the DC level constant,
independent of process spread.
2.
The AF output amplifier (10 dB) provides the required
output level by a rail-to-rail output stage. This amplifier
makes use of an input selector for switching to FM
de-emphasis or mute state, controlled by the mute
switching voltage.
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 all audio output signals the constant reference voltage
cannot be used because large output signals are required.
Therefore these signals refer to half the supply voltage to
achieve a symmetrical headroom, especially for the
rail-to-rail output stage. 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
TDA9808 Single standard VIF-PLL with QSS-IF and FM-PLL demodulator
TDA9808T Single standard VIF-PLL with QSS-IF and FM-PLL demodulator
TDA9809 Single standard multimedia IF-PLL and FM radio demodulator
TDA9809M Single standard multimedia IF-PLL and FM radio demodulator
TDA9810 Multistandard VIF-PLL with QSS-IF and AM demodulator
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TDA9808 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Single standard VIF-PLL with QSS-IF and FM-PLL demodulator
TDA9808T 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Single standard VIF-PLL with QSS-IF and FM-PLL demodulator
TDA9809 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Single standard multimedia IF-PLL and FM radio demodulator
TDA9809M 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Single standard multimedia IF-PLL and FM radio demodulator
TDA9809M/V1,112 功能描述:射頻無(wú)線雜項(xiàng) MULTIMEDIA IF PLL RoHS:否 制造商:Texas Instruments 工作頻率:112 kHz to 205 kHz 電源電壓-最大:3.6 V 電源電壓-最小:3 V 電源電流:8 mA 最大功率耗散: 工作溫度范圍:- 40 C to + 110 C 封裝 / 箱體:VQFN-48 封裝:Reel