TDA8296 Datasheet, PDF (69/87 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
The following relation gives the value of the full-scale current I_FS in function of the bias
resistance value and value of B_DA_V[5:0] (part of register 0x35h) and value of
B_DA_S[5:0] (part of register 0x36h) (B_DA_V or B_DA_S):
I_FS
=
1_----._-2_---1_---6_-----V_{---R----S--E---T- × 1-- × -6---4----+-----B----_---D----A----_---V---/--S- × 64}
R_RSET
5
48
(2)
0 ≤ B_DA_V/S ≤ 63
For programming of B_DA_V see Table 50, for B_DA_S see Table 51.
45
DAC current
[mA]
35
25
15
001aam357
(1)
(2)
(3)
5
0
10
20
30
40
50
60
70
DAC reg (dec)
(1) I_{V_IOUTP} for R_RSET = 1 kΩ
(2) I_{V_IOUTP} for R_RSET = 1.5 kΩ
(3) I_{V_IOUTP} for R_RSET = 2 kΩ
Fig 28. TDA8296 calculated DAC characteristic
The DAC signal range used for CVBS and sound signal is reduced to provide headroom.
The signal headroom is shown in Figure 29 and Figure 30. The full scale DAC current
corresponds to digital input value of 1034. For the pins VIOUT_P and SIOUT_P the
corresponding signal shapes of CVBS and sound signal can be mapped linear to the full
scale DAC current. For the CVBS signal the sync level is fixed, the white level depends
also on register value CVBS_LVL[7:0]. For the sound signal the DC level is fixed.
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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