
d.c. supplies 257
113.12
(ii / =
100 + 1500
(iii) V
L
= 0.0707 x 1500
(See program 226, page 256.)
14.6
Voltage regulators
Voltage regulator circuits are connected in power supplies between
the filter output and the load resistance. Figure 14.12 shows one of
the most common regulator circuits consisting of a series resistor R$
and a zener diode. The circuit works on the principle that the
current flowing through the diode, /
D
, can vary considerably with
very little change in the voltage across the diode, and hence across
the load R
L
. If the load current increases or decreases, the current
through the diode will decrease or increase by the sam ...