Question

Determine the resistance values for a voltage divider that must meet the following specifications:_______.

a. The current drawn from the source under unloaded condition is not to exceed 5 mA.
b. The sourcevoltage is to be 10 V, and the required outputs are to be 5 V and 2.5 V.
c. Sketch the circuit.
d. Deter-mine the effect on the output voltages if a load is connected to each tap one at a time.

Answer 1

i) when circuit is unloaded : R1 + R2 = 2kΩ.

ii) when 5V output voltage is applied : R1 = 1 kΩ , R2 = 1 kΩ

iii) when 2.5 v output voltage is applied : R1 = 1500 Ω, R2 = 500 Ω

iv) when: R1 = 1 kΩ , R2 = 1 kΩ is connected in parallel output voltage < 5 V

When : R1 = 1500 Ω, R2 = 500 Ω is connected in parallel output voltage > 2.5V

Step-by-step explanation:

Current drawn from source under loaded condition ≤ 5 mA

source voltage = 10 v , required output = 5 v , 2.5 v

attached below is the sketch of the circuit

Resistance values

i) when the circuit is unloaded

Req = R1 + R2 = 2 kΩ ( Req = Vs / I = 10 / 5*10^-3 = 2 kΩ )

ii) when output voltage = 5 v

we will apply voltage divider rule

R1 = 1 kΩ ,

R2 = 1 kΩ

iii) When the output voltage = 2.5 v

applying voltage divider rule

R1 = 1500 Ω

R2 = 500 Ω

iv) when the load is connected to each tap one at a time

i.e. when the resistance are in parallel

when: R1 = 1 kΩ , R2 = 1 kΩ is connected in parallel output voltage < 5 V

When : R1 = 1500 Ω, R2 = 500 Ω is connected in parallel output voltage > 2.5V

attached below is the detailed solution to the given problem