Bt860/861
4.0 Applications
Multiport YCrCb to NTSC/PAL /SECAM
4.1 PC Board Considerations
4.1.3 Device Decoupling
For optimum performance, all decoupling capacitors should be located as close as
possible to the device, and the shortest possible leads should be used to reduce the
lead inductance. Chip capacitors are recommended for minimum lead inductance.
Radial lead ceramic capacitors can be substituted for chip capacitors and are
better than axial lead capacitors for self-resonance. Values chosen have
self-resonance above the pixel clock frequency.
4.1.4 Power Supply Decoupling
The best power supply performance is obtained with 0.1 µF ceramic capacitors
decoupling each group of power pins to ground. Place the capacitors as close as
possible to the device power pins and ground pins and connect with short, wide
traces. Table 4-1 is a typical parts list.
The 47 µF capacitor illustrated in Figure 4-1 is for low-frequency power
supply ripple; the 0.1 µF capacitors are for high-frequency power supply noise
rejection.
A linear regulator is recommended to filter the analog power supply if the
power supply noise is excessive. This is especially important when using a
switching power supply.
Figure 4-2. Recommended Crystal Circuit
Bt860/861
C19
XTI
R1
XTAL
XTO
C20
NOTE(S): For typical parts list, see Table 4-1.
861_039
D860DSA
Conexant
4-3