Question 8.1: Current and Voltage of a Diode For the circuit shown in Figu...
Current and Voltage of a Diode
For the circuit shown in Figure 8.8, find I and V when:
a. V_S = -10 V
b. V_S = -1 V
c. V_S = 0.5 V
d. V_S = 8 V
a. Referring to Figure 8.7, V_{S}=-10 V means V_1-V_2=-10 V. Therefore, the diode is reverse biased (OFF) and the current flowing through it I = 0 and the voltage across the diode V=-10 V.
b. Similar to part a, I = 0 and V=-1 V.
c. For the silicon diode, V_\gamma=0.7
0<V_1-V_2=V_{S}=0.5<V_\gamma=0.7Therefore, the diode is forward biased but it is OFF because there is no sufficient voltage to turn it ON. Therefore, I = 0 and V=0.5 V.
d. Next, V_1-V_2=V_{S}=8 V>V_\gamma=0.7.
Therefore, the diode is forward biased and it is ON. Accordingly:
\begin{aligned}&V=0.7 V \\&I=\frac{V_{S}-V_\gamma}{R}=\frac{8-0.7}{2}=3.65 mA\end{aligned}
Related Answered Questions
Question: 8.18
Verified Answer:
DC analysis
The DC equivalent circuits are shown i...
Question: 8.34
Verified Answer:
First, given the voltage source, v_S(t)[/la...
Question: 8.33
Verified Answer:
Go to “Place Part” (see Figure 2.63) and type “Qbr...
Question: 8.32
Verified Answer:
The PSpice model editor is required to set up a Ze...
Question: 8.31
Verified Answer:
The voltage source is v_i(t) = 5 si...
Question: 8.30
Verified Answer:
The voltage source is given: V(t)=12V .
a. R = 1 k...
Question: 8.29
Verified Answer:
The input voltage is amplified using two amplifier...
Question: 8.27
Verified Answer:
At node “b”:
V_b = V_i (8.56)
T...
Question: 8.26
Verified Answer:
Following the given procedure, first calculate [la...
Question: 8.25
Verified Answer:
It is clear that when both A and B are low (0), th...