# Question 11.4: Consider the following situation in the FET series gate, Vs ......

Consider the following situation in the FET series gate,$\ V_{s}$ = ± 2 V,$\ R_{s}$ = 100 Ω,$\ R_{L}$ = 10 kΩ. The FET has the following parameters:

$\ V_{GS(OFF)max}$ = −10 V and$\ R_{D(ON)}$ = 20 Ω

Calculate the voltage levels of the control signal,$\ I_{D}$, error due to$\ R_{S}$ and error due to$\ R_{D(ON)}$.

Step-by-Step
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The control signal should have a value$\ V_{1}$ for$\ Q_{1}$ to be ON.
Therefore,$\ V_{1} = V_{s(peak)}$ = 2 V
For$\ Q_{1}$ to be OFF, the control signal should be$\ –V_{2}$:
$\ −V_{2} = −(V_{s(peak)} + V_{GS(OFF)max} + 1V)$
$\ −V_{2}$ = −(2 + 10 + 1) = −13 V

$\ I_{D} = \frac{V_{S}}{R_{S} + R_{D(ON)}+ R_{L}} = \frac{2 V}{100 + 20 + 10000}$  = 197.4 μA

$\ I_{D}R_{S} = 197 × 10^{−6} × 0.1 × 10^{3}$ = 19.74 mV

Error due to$\ R_{S} = \frac{19.74 mV}{2V}$  × 100 % = 0.987 %

$\ I_{D}R_{D(ON)}$ = 197.4 μA × 20 Ω = 3.948 mV

Error due to$\ R_{D(ON)} = \frac{3.948 mV}{2}$  × 100 % = 0.197 %

Question: 11.1

## In the circuit shown in Fig. 11.16(a), RL = R1 = 100 kΩ , R2 = 50 kΩ and the signal has a peak value of 20 V. Find (a) A (b) VC(min) (c) Vn(min) (d) Ri when the diodes are ON ...

(a) \ A = \frac{a}{1 + a\frac{R_{1}}{2R_{L}...
Question: 11.2

## For the four-diode gate shown in Fig. 11.20(a), RL = R2 = 100 kΩ and R1 = 1 kΩ, Rf = 25 Ω, Vs = 20 V. Calculate (a) A (b) V(min) (c) VC(min) (d) Vn(min) for V = V(min) ...

(a) We have: \ R = \frac{R_{1}R_{2}}{R_{1} ...
Question: 11.3

## For the four diode gate shown in Fig. 11.21(a), Vs = 20 V, RL = 200 kΩ , RC = 100 kΩ, Rf = 0.5 kΩ, R = Rs = 1 kΩ. Find Vn(min), A and VC(min). ...

(i) From Eq. (11.17), \ V_{n(min)} = V_{s}[...
Question: 11.5

## In the circuit shown in Fig. 11.16(a), RL = R1 = 200 kΩ, R2 = 100 kΩ and the signal has a peak value of 10 V. Find (a) A (b) VC(min) (c) Vn(min) (d) Ri ...

(a) \ A = \frac{α}{1 + α(R_{1}/2R_{L})}[/la...
Question: 11.6

## For the four-diode gate shown in Fig 11.20(a), RL = R2 = 50 kΩ and R1 = 1 kΩ, Rf = 25 Ω, Vs = 10 V. Calculate (a) A (b) V(min) (c) VC(min) (d) for V = V(min) ...

(a) We have \ R = \frac{R_{2}R_{1}}{R_{2} +...
The control signal should have a value\ V_{...