TDA8296 Datasheet, PDF (71/87 Pages) NXP Semiconductors – Digital global standard low IF demodulator for analog TV and FM radio

NXP Semiconductors
TDA8296
Digital global standard low IF demodulator for analog TV and FM radio
13.4 ADC connection
The input signals of the ADC (IF_POS and IF_NEG) can be either AC coupled by means
of two capacitors or connected directly to the inputs (DC coupled). In case of AC coupling,
the DCIN bit (see Table 48) should be set to logic 0, which enables the internal resistive
dividers between V_{DDA(ADC)(1V2)} and V_SSD1 to take care of the correct DC biasing of the
input signals.
In case the input signal is DC coupled, the input resistor network can be switched off by
setting the DCIN bit to logic 1. When using the ADC in this mode, the Common mode level
of the input signal should be at (0.5 / 1.2) × V_{DDA(ADC)(1V2)} ± 200 mV.
Please note that during power-down the DC biasing network at the input will be switched
off in order to reduce current consumption. During Sleep mode however the resistor
network will remain active.
13.5 Reset operation
13.5.1 Hardware reset
RST_N
minimum width at LOW is 4 × T_XIN
XIN
T_XIN
the TDA8296 enters
immediately in its reset mode
Fig 31. Hardware reset operation
TDA8296 normal operation
starts after 4 falling edges of XIN
008aaa144
After a hardware reset, the registers are set to default (power-on reset values) according
to Table 9. M/N standard is the default standard.
13.5.2 Software reset
A software reset can be done each time something has been programmed. The software
reset does not affect the content of the registers but clears the flip-flops in the design. For
the activation of the software reset see Table 47 bit CLB.
13.6 Application hints
The DAC application can be adapted to a wide range of application needs. The data sheet
describes 3 different use cases as shown in Figure 23 to Figure 25.
The default application (also used for specification) is shown in Figure 23. This application
supports 75 Ω DC termination for the video CVBS and > 1 kΩ AC/DC termination for the
SSIF or mono audio sound signal. This application is e.g. preferred for device evaluation.
TDA8296
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 3 March 2011
© NXP B.V. 2011. All rights reserved.
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