Epson LX-810 Technical Manual page 51

Feedback Circuit
A voltage switching circuit is formed
voltage is fed back to PPC494C.
The line between R 12 and R 16 feeds back to the positive terminal of EA 1 in the PPC494C, where it
is compared against the standard + 5V voltage. The electric potential of the feedback line becomes
the same as the standard potential at 24.3V, as shown by the equation below. If the voltage exceeds
lowered, and, as a result, the +24V potential drops. This action is repeated in order to maintain a stable
voltage of +24V.
5 V X ( R l 1 + R 1 2 + R 1 6 ) = 24 a v
(RI 1 + R12)
by RI 1, R 12, and R16, and the potential of the +24V output
Figure 2-17. Voltage Feedback Circuit
2-15
RI 6
1 9.6K
4.75 K
RI 1
3 1 6
REV.-A