# Can I take the voltage across diode to be same as the input voltage in a limiting circuit?  My doubt is a trivial one, can I take VD1 and VD2 to be V1? If so doing that doesn't make sense to me 'cause when the current flows VD1 is certainly not equal to V1. This isn't a Homework question, I found a similar question in my textbook with D2 reversed (Given above) and there I can understand why VD1 equals V1, as for the off condition no current flows through the 10K resistance but here this isn't the case. If I'm right then the following solution is wrong, how should I proceed then?

Any help is highly appreciated.

• In your notes D1 and D2 are in the same direction but in Figure E4.26 they're in opposite directions !!! In note's your circuit (diodes in same direction) you could simplify the circuit to one diode, a 5 V battery and a 5 kohm resistor. Your calculations do assume diodes as in Figure E4.26. I would like to suggest that before throwing calculations at the problem, first think and envision what the circuit does. – Bimpelrekkie Apr 18 at 6:57

In the textbook when the input is between +5 and -5 both diodes are reverse biased so they do not conduct and the signal crcuit is just a 10K resistor,

in the case when either diode is forwards biased the signal now encounters a resistive divider.

So you get $$\ V_i + 5 \over 2 \$$ or $$\ v_i + -5 \over 2 \$$ depending on which diode is conducting