TS EAMCET 11-Sep-2020 Shift 1 Solved Paper

Given, potential difference across diode,
VD=0.5V
Maximum current in forward bias,
i=20mA=20×10−3A
⇒ Resistance of diode,
RD=‌

VD

i

=‌

0.5

20×10−3

=25Ω
Now, another resistance of 125Ω is connected with this diode in series.
So, effective resistance,
R=25+125=150Ω
Clearly, maximum voltage to be used during forward bias,
V‌‌=iR=20mA×150Ω
‌‌=3000mV=3.0V