參數(shù)資料
型號: TDA8722M
廠商: NXP SEMICONDUCTORS
元件分類: 消費(fèi)家電
英文描述: I2C-bus programmable modulator for negative video modulation and FM sound
中文描述: SPECIALTY CONSUMER CIRCUIT, PDSO20
文件頁數(shù): 8/28頁
文件大小: 196K
代理商: TDA8722M
1998 Jun 23
8
Philips Semiconductors
Product specification
I
2
C-bus programmable modulator for
negative video modulation and FM sound
TDA8722
The bits T0 to T2 are available for test purposes and the possibilities are shown in Table 5.
Table 5
Test modes
Notes
1.
In ‘TPSG on’ mode the video carrier is modulated by the test signal consisting of a synchronization pulse and two
vertical white bars on a black screen. This mode should be selected to adjust the TV set receiving the modulated
signal to the right frequency.
In ‘RF oscillator off’ mode, the RF oscillator and the RF mixer are switched-off and there is no RF carrier coming out
of the device. This mode can be selected to avoid RF radiation to other parts when the modulator output is not used.
In ‘balance test’, the video carrier is over modulated. This simplifies residual carrier measurements.
In ‘f
ref
’ and ‘f
DIV
’ modes, the reference frequency f
ref
in the phase comparator or the divided RF oscillator frequency
f
DIV
is available on the output Port pin. This mode requires that bit P0 = 0.
The ‘high-impedance test’ mode may be used to inject an external tuning voltage to the RF tank circuit, to test the
oscillator. In this mode, the phase detector is disabled and the external transistor of the tuning amplifier is
switched-off. The AMP output (pin 7) is LOW (<200 mV).
In the ‘phase detector disabled’ mode, it is possible to measure the leakage current at the input of the tuning amplifier,
on the CP pin. In this mode the RF oscillator is off, and the baseband TV channel signal is present on the RF outputs
for testing the audio and video parts.
2.
3.
4.
5.
6.
T0
T1
T2
OPERATIONAL MODE
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
normal operation
Test Pattern Signal Generator (TPSG) on; note 1
RF oscillator off; note 2
balance test; note 3
f
ref
out (if p0 = 0); note 4
high-impedance test; note 5
f
DIV
out (if p0 = 0); note 4
phase detector disabled; baseband signals on RF outputs; note 6
The possibilities of bit P0, which controls the output Port
(pin 14) are given in Table 6.
The Port is an NPN open-collector type. For monitoring the
f
ref
or f
DIV
frequency on the output Port, the P0 bit must be
logic 0 to let the output Port free.
Table 6
Output Port programming
P0
OUTPUT PORT STATE
0
1
off; high impedance
on; sinking current
相關(guān)PDF資料
PDF描述
TDA8722 IIC-bus programmable modulator for negative video modulation and FM sound(負(fù)向視頻調(diào)制和調(diào)頻聲的IIC總線可編程調(diào)制器)
TDA8722T I2C-bus programmable modulator for negative video modulation and FM sound
TDA8725T Antenna signal processor
TDA8730 PLL FM demodulator for DBS signals
TDA8732 NICAM-728 demodulator NIDEM
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TDA8722T 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:I2C-bus programmable modulator for negative video modulation and FM sound
TDA8725T 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:Antenna signal processor
TDA8730 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:PLL FM demodulator for DBS signals
TDA8732 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:NICAM-728 demodulator NIDEM
TDA8735 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:PLL frequency synthesizer