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Ryan Phway
Feb 8, 2015, 11:52 AM
Find the range of Vin So that

(a)The outputs Vo1 = 2V and Vo2=2V

(b) The outputs Vo1=14V and VO2=2V

(c) The outputs Vo1=14V and Vo2=14V

Given that op amp has +Vsat=+14V and -Vsat=+2v.. the answer for part a is Vin is less than 5 v.. I've got the answer for part a =5V.. I use the formula,V3=(R3/R1+R2+R3)*Vin=+15V..
for answer b is 5 v is less than vin and vin is less than 10V...

for answer C is 10V is less than Vin.. I use that formula,V1=(R2+R3/R1+R2+R3)*Vin=+15V... I'll get an answer 10v..

Ryan Phway
Feb 8, 2015, 12:31 PM
(a)Determine the voltages at V1,V2,V3.. the answers are -7.5V for v1.. V2=0V and V3 for 7.5V

(b)state type of op-amplifier implemented for U1,U2 and U3 respectively... U1=non-inverting amplifier,U2=amplifier and U3=voltage follower...

(c)Determine Voltages at Va Vb and Vc.. Va=-7.5V,Vb=0V and Vc=15V..

Assume the supply voltages to all operational amplifiers are +or- 15 V..

before i do the part a,do i need to find Current I? R1,R2,R3,R4 are 1kohm for each... R6 And R7 are 10kohm.. R8=10KOHM.. R5=1Kohm... I've got the an answer for current I is 7.5mA..

guys can i have your working step and using the formulae with it..