sm5320av Nippon Precision Circuits Inc, (NPC), sm5320av Datasheet - Page 18

• Manufacturer Part Number: sm5320av
• Description: 5-channel Video Buffer With Built-in Wideband Lpf
• Manufacturer: Nippon Precision Circuits Inc, (NPC)

R
R
1.8kΩ. In power-down mode and filter bypass mode, no current flows into R
Note. A value other than 1.8kΩ will change the current consumption of SM5320A. In the determination of
Half fc Mode
In half fc mode, the CH-2 and CH-3 cutoff frequency is 1/2 that of the CH-1 cutoff frequency setting. Half fc
mode is useful for systems where the sampling frequency varies due to luminance (Y) and color difference sig-
nal (Cr, Cb) requirements as in component signals.
Group Delay Characteristics
The group delay varies with the cutoff frequency setting. Note also that in half fc mode, the group delay
between CH-1 and CH-2/CH-3 varies.
Filter Bypass Mode
In filter bypass mode, the internal lowpass filter in SM5320A is bypassed and the signal is input to the output
buffer stage directly. In filter bypass mode, the input type and output gain are set just as for filter mode. But the
cutoff frequency setting and fc mode setting have no effect on the outputs. In this mode, the passband fre-
quency is 80MHz (typ), which can support SXGA-class signals.
Power-ON Reset
When power is applied, an internal power-ON reset circuit operates initializing the internal register flags to
their default settings. At power-ON, all supplies should be applied simultaneously.
Reference Voltage (REF)
The REF pin is internal reference voltage output. A 10 µF capacitor connected between pin and ground is rec-
ommended for stability of movement.
ISET
ISET
resistance value, caution should be taken to ensure the power dissipation does not exceed the absolute
maximum rating for the package.
controls the internal current source, and its connection is essential. The recommended value (R
50
45
40
35
30
25
20
15
10
Figure 2. Cutoff frequency vs. FCDATA (R
5
0
0
32
64
96
SM5320A
FCDATA
128
160
ISET
192
= 1.8kΩ)
ISET
224
SEIKO NPC CORPORATION —18
.
256
ISET
) is