cx25870 Conexant Systems, Inc., cx25870 Datasheet - Page 144

• Manufacturer Part Number: cx25870
• Description: Video Encoder With Adaptive Flicker Filtering And Hdtv Output
• Manufacturer: Conexant Systems, Inc.

3.0 PC Board Considerations
3.6 Applications Information
Table 3-3. Hardware Modifications to Bt868/869-based PCB Required to Accommodate the CX25870/871 (3 of 3)
3-14
NOTE(S):
75
76
78
N/C = No connect
COMP
VREF
FSADJUST
COMP
VREF
FSADJUST
each recommendation contained in
To ensure proper operation of the CX25870/871, the designer must adhere to
A 0-10 ohm resistor between COMP and 0.1 !F capacitor (which is connected to VAA)
was originally recommended for Bt868/9-designs.
The 0-10 ohm resistor placed between the 0.1 !F cap and the COMP pin was
recommended to better tune the COMP circuit to prevent an internal op-amp from
oscillating. Based on the Bt868/9's DAC performance over time and the CX25870/1's
continued usage of these same DACs, this resistor was deemed to not be necessary
and should be removed for all CX25870/1 designs.
Capacitor from VREF to GND must be 1.0 !F for the CX25870/1. Capacitor from VREF
to GND must be 0.1 !F for the Bt868/9.
RSET, the resistor from FSADJUST pin to GND, must be 75 ", +/- 1% for all
CX25870/1-based designs.
RSET must be 100 ohm, +/- 1% for all Bt868/9-based designs.
Conexant
Flicker-Free Video Encoder with Ultrascale Technology
Table
3-3.
CX25870/871
100381B