ak8825 AKM Semiconductor, Inc., ak8825 Datasheet - Page 85

• Manufacturer Part Number: ak8825
• Description: Hd/sd Multi Format Video Encoder With 3ch Dac
• Manufacturer: AKM Semiconductor, Inc.

(1) 525i waveform (EIA-770.2-C)
[Sync waveform level]
HDVRATIO-bit of HD Block Control Register [SubAddress0x07]
HD Block Control Register
Sub Address 0x07
(1-1) 525i Sync waveform
Design Spec (T=1/13.5MHz)
* 286mV sync waveform can be output by register setting.
Rev-E-00
Total line period(derived)
Sync rise time
Horizontal Sync
H-Blanking start to H-reference
H reference to H-blanking end
Only 525i output mode, AK8825 can output both of 286mV sync-waveform and 300mV sync-waveform with setting
HDWSS
HDVRATIO-bit
bit 7
H o r iz o n ta l
r e f e r e n c e p o in t
9 0 %
0
1
5 0 %
1 0 %
H b la n k in g s ta r t
t o H - r e f e r e n c e
HDCFLT1
bit 6
H o r iz o n ta l B la n k in g r is e t im e
9 0 %
5 0 %
1 0 %
HDCFLT0
bit 5
measurement
S y n c r is e t im e
10% - 90%
Measurement Point
Sync waveform Level
point
300mV (EIA770.2-A)
286mV (EIA770.1-A)
50%
S y n c
50%
50%
HDYFLT1
H r e f e r e n c e to B la n k in g E n d
bit 4
5 0 %
5 0 %
Fig. 121
85
63.556
value
140
4.7
HDYFLT0
3 0 0 m V *
bit 3
Reference Clock
122T
16T
Reserved
Recommended
bit 2
tolerance
+/- 0.1
+/- 20
COLSNCEN
bit 1
units
usec
nsec
usec
default Value 0x00
HDVRATIO
bit 0
2008/03
[AK8825]