PNX8510HW/B1 PHILIPS [NXP Semiconductors], PNX8510HW/B1 Datasheet - Page 81

• Manufacturer Part Number: PNX8510HW/B1
• Description: Analog companion chip
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
9397 750 12612
Product data
10.2 DAC reconstruction filter
10.3 Video DACs of primary and secondary video channels
The reference resistor is dimensioned to be 18 kΩ. Since the reference voltage Vref
is nominally half the supply voltage, the I/V conversion resistor must be dimensioned
by:
Rconv = Vout(rms)/Vref ⋅ √2/(12 ⋅ α) ⋅ Rref
For an rms output voltage of 1000 mV rms, a reference voltage of 1.65 V, a reference
resistance of 18 kΩ and a maximum digital input level of 0.521 (-5.67 dB), the I/V
conversion resistor should be 2470 Ω.
Figure 33
The video DACs used in both the primary and secondary video channels employ
segmented current mode architecture. The programming feature of DACs is valid for
both the primary and secondary video channels.
The primary video channel has in its path four DACs: R, G, B and CVBS. The
programming option “Fine Adjust” – via the common four bits of I
simultaneously adjust the central output level of all four DACs in a range of ± 7% in
1% increments. Please note the four bits are signed values.
programming values.
Fig 33. DAC reconstruction filter
shows the circuitry for the reconstruction filter of the video D/A converters.
LUMA1
VOUT6
CVBS2
Rev. 04 – 12 January 2004
RV5
75
RV6
75
RV7
75
CV3
390 pF
CV5
390 pF
CV7
390 pF
120 pF
2.7 H
120 pF
2.7 H
120 pF
2.7 H
C40
C41
C42
L3
L5
L7
CV4
560 pF
CV6
560 pF
CHROMA1_OUT
CV8
560 pF
2.7 H
2.7 H
2.7 H
L4
L6
L8
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
J6
4
2
PNX8510/11
Analog companion chip
Table 45
RCA jack
S-video
7
LUMA1_OUT
J7
6
2
C [3:0] – can
MDB661
5
3
1
shows the
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