Kyocera FS C5020N - Color LED Printer Service Manual page 167

The primary transfer roller bias is triggered by a serial data which is generated by the engine controller PWB and derived
from the bias high voltage PWB. The engine controller PWB converts current and voltage into serial data and applies it to
the bias high voltage PWB. The bias high voltage PWB then uses D/A converter (IC501) and revert it into analog voltage.
The analog voltage is applied to the high voltage output circuit which in turn applies the secondary transfer roller with the
bias accordingly.
Secondary
transfer
roller
Bias high voltage PWB
Secondary
transfer
roller bias
High
-40 mA
voltage
output
circuit
Figure 2-1-34 Secondary transfer unit block diagram
6
HVBDATD
D/A
7 HVBCLKD
converter
8 HVBLATD
(IC501)
2F3/2F4
Engine controller PWB
YC5-6
YC5-7
YC5-8
2-1-25