The 741 Op-Amp

** Circuit Description **

* power supplies 
Vcc 25 0 DC +15V 
Vee 26 0 DC -15V 

* DC & AC differential-mode signal level 
Vd 101 0 DC -314.1uV AC 1V 
Rd 101 0 1
EVp 1 100 101 0 +0.5 
EVm 2 100 101 0 -0.5 
* common-mode signal level 
Vcm 100 0 DC 0V 

* 1st or input stage 
Q1 4 1 12 npn
Q2 4 2 13 npn 
Q3 7 3 12 pnp 
Q4 8 3 13 pnp 
Q5 7 9 10 npn 
Q6 8 9 11 npn 
Q7 25 7 9 npn 
Q8 4 4 25 pnp 
Q9 3 4 25 pnp
R1 10 26 1k 
R2 11 26 1k 
R3 9 26 50k 

* 2nd stage 
Q13B 16 6 25 pnp 0.75 
Q16 25 8 14 npn 
Q17 16 14 15 npn 
R8 15 26 100
R9 14 26 50k
Cc 8 16 30p

* output or buffer stage
Q13A 17 6 25 pnp 0.25
Q14 25 17 23 npn 3
Q18 17 18 19 npn
Q19 17 17 18 npn
Q20 26 19 21 pnp 3
Q23 26 16 19 pnp
R6 22 23 27
R7 21 22 27
R10 18 19 40k

* short-circuit protection circuitry
Q15 17 23 22 npn
Q21 20 21 22 pnp
Q22 8 20 26 npn
Q24 20 20 26 npn
R11 20 26 50k

* biasing stage
Q10 3 5 24 npn
Q11 5 5 26 npn
Q12 6 6 25 pnp
R4 24 26 5k
R5 6 5 39k

* transistor model statements
.model npn NPN ( Bf=200 Br=2.0 VAf=125V Is=10fA Tf=0.35ns
+ Rb=200 Rc=200 Re=2 Cje=1.0pF Vje=0.70V Mje=0.33 Cjc=0.3pF
+ Vjc=0.55V Mjc=0.5 Cjs=3.0pF Vjs=0.52V Mjs=0.5)
.model pnp PNP ( Bf=50 Br=4.0 VAf=50V Is=10fA Tf=30ns
+ Rb=300 Rc=100 Re=10 Cje=0.3pF Vje=0.55V Mje=0.5 Cjc=1.0pF
+ Vjc=0.55V Mjc=0.5 Cjs=3.0pF Vjs=0.52V Mjs=0.5)

** Analysis Requests **
.AC DEC 10 0.1Hz 100MegHz

** Output Requests **
.PLOT AC Vdb(22) cph(v(22))
.PRINT AC mag(I(EV+)) mag(I(EV-))
.probe
.end