|
|
PDF TDA4340X Data sheet ( Hoja de datos )
| Número de pieza | TDA4340X | |
| Descripción | Stereo Decoder/Noise Blanker | |
| Fabricantes | Siemens Semiconductor | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de TDA4340X (archivo pdf) en la parte inferior de esta página. Total 15 Páginas | ||
|
No Preview Available !
Stereo Decoder/Noise Blanker
TDA 4340X
1 Overview
1.1 Features
• Internal reference voltage source
• Adjustment free oscillator with
ceramic resonator 456 kHz
• Pilot dependent mono/stereo switching with
hysteresis
• Stereo indicator output
P-DSO-20-1
• Analogue control of mono/stereo change over (stereo noise control, SNC)
• Pilot canceller (19 kHz)
• Adjacent channel noise suppression (114 kHz)
• MUTE facility
• Analogue control of deemphasis (high cut control, HCC).
• Stereo inputs for additional signal source at output amplifiers
• Interference noise detector with integrated high-pass filter
• (IF level signal or MPX input)
• MPX input low-pass filter
• Noise blanking at MPX demodulator outputs
• Input and output level adjustable (resistor values)
Type
TDA 4340X
Ordering Code
Q67000-A5058
Package
P-DSO-20-1
1.2 Application
The TDA 4340X is an integrated circuit providing the stereo decoder function and noise
blanking for FM car radio applications.
Semiconductor Group
1
04.96
1 page  
TDA 4340X
2 Circuit Description
Power Supply, Reference Current
A temperature stable, low noise reference voltage generator is used for better ripple
rejection and for the generation of a reference current. This current is used as a time
base for the deemphasis, the gate time of the pulse former, and the pilot cancellation,
avoiding temperature and tolerance effects.
MPX Input, MPX Filter
Adjusting the value of the input resistor, the MPX input can be adapted to the output level
of the FM demodulator. A 4-pole low-pass filter determines the bandwidth of the MPX
signal.
Voltage Controlled Oscillator, Phase Detector
The 456 kHz oscillator and the frequency dividers are used as walsh function generators
(suppression of 3rd order harmonics) for:
– 38 kHz for the stereo decoder
– 19 kHz inphase for phase detector and pilot cancellation
– 19 kHz quadrature for the phase detector.
The phase detector locks the on-chip 19 kHz signal to the pilot tone in the MPX signal at
90° phase.
Pilot Detector, Pilot Indicator, Pilot Cancellation
The voltage at the pilot detector output is proportional to the pilot tone input level. If that
level is high enough, the pilot indicator output is activated and the pilot Cancellation
turned on: a 19 kHz signal proportional to the voltage at the pilot detector output is added
to the MPX signal with inverse polarity, cancelling the 19 kHz pilot tone.
Interference Detector, Noise Detector, Pulse Former
The signal from the interference input (MPX or field strength signal) passes a 4-pole
high-pass to the noise blanking circuitry. The average noise level is stored on an external
capacitor. The interference detector compares the actual noise level with that stored on
the capacitor and triggers the pulse former if there is a significant difference. The pulse
former generates a gate pulse for the HCC block. During that pulse time the outputs of
the deemphasis circuit are switched to hold mode.
Semiconductor Group
5
04.96
5 Page 
TDA 4340X
3.3 AC/DC Characteristics (cont’d)
VS = 10 V, TA = 25 °C
Parameter
Symbol
Limit Values Unit
min. typ. max.
Suppression pulse
duration
40 µs
Input offset current I13, I141) – 50 0
50 nA
Pulse threshold
V 1)
6 burst
130 200 mVpp
1) No subject of production testing.
Test Condition
100 kHz single burst repetition
rate 100 Hz both polarities
Cin, 6 = 1 nF
Note: The listed characteristics are ensured over the operating range of the integrated
circuit. Typical characteristics specify mean values expected over the production
spread. If not otherwise specified, typical characteristics apply at TA = 25 °C and
the given supply voltage.
Semiconductor Group
11
04.96
11 Page | ||
| Páginas | Total 15 Páginas | |
| PDF Descargar | [ Datasheet TDA4340X.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| TDA4340X | Stereo Decoder/Noise Blanker | Siemens Semiconductor |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |