4.0 Parametric Information
CX25870/871
4.2 AC Electrical Parameters
Flicker-Free Video Encoder with Ultrascale Technology
Table 4-4. AC Characteristics for CX25870/871 (3 of 3)
HDTV Output Timing Characteristics: 1080i (see Figure 4-9)
Parameter
Symbol
Min
Typical
Max
Units
ns
Lowsync width
α
β
—
—
—
—
—
—
—
—
598.8
28.385
598.8
1.796
2.588
54.5
—
—
—
—
—
—
—
—
Start of line to end of active video
Highsync width
µs
ns
µs
µs
ns
µs
µs
χ
Rising edge of sync to start of broad pulse
Start of line to start of active video
Sync rise time
δ
ε
φ
Total line time
—
—
29.685
25.778
Active line time
HDTV Output Timing Characteristics: 720p (see Figure 4-10)
Parameter
Symbol
Min
Typical
Max
Units
Lowsync width
a
b
—
—
—
—
—
—
—
—
548
—
—
—
—
—
—
—
—
ns
µs
ns
µs
µs
ns
µs
µs
Start of line to end of active video
High sync width
20.54
548
c
Rising edge of sync to start of broad pulse
Rising edge of sync to start of active video
Sync rise time
d
3.53
3.53
54.7
22.2
17.16
e
—
—
—
Total line time
Active line time
NOTE(S):
1. Guaranteed by characterization; NTSC output, no vertical or horizontal scaling. Flicker Filter and other internal low-pass filters
bypassed, and contrast, brightness, saturation levels set to full scale.
(2)
100/7.5/100/7.5 Color bars normalized to burst.
Guaranteed by design.
Control pins are defined as: BLANK*, HSYNC*, VSYNC*, FIELD, CLKO, CLKI, RESET*, PAL, and SLAVE.
DAC output load < 75 pF. HSYNC*, VSYNC*, BLANK*, and FIELD output load < 75 pF. As the above parameters are
(3)
(4)
(5)
guaranteed over the full temperature range, temperature coefficients are not specified or required. Typical values are based on
nominal temperature, i.e., room temperature, and nominal voltage, i.e., 3.3 V.
There are numerous power-down options. This value was determined by setting SLEEP_EN, DIS_CLKI, DIS_CLKO, BY_PLL,
(6)
XTL_BFO_DIS, XTAL_PAD_DIS bits and pulling the SLEEP pin high.
This value was determined by setting BY_PLL, SLEEP_ED, DIS_CLKI, DIS_CLKO, XTAL_BFO_DIS bits.
To ensure that the encoder performance falls within DC and AC electrical limits, no more than one DAC should be disabled at
(7)
(8)
any time.
4-6
Conexant
100381B
CONEXANT [ CONEXANT SYSTEMS, INC ]
