2 2. Operational Amplifier/OP OP-AMP IC OP LM74 IC OP Black Box OP. 2. 3. 4. 5. 6. 0 0 OP LM74 (Z in ) 2MΩ (Z out ) 75Ω (A) 06dB2 0 5 OP OP OP LM74 DIP OP = A ( ) OP 2
8 NCNo Connection 2 7 3 6 4 5 : LM74 TOP VIEW) 2.. (Input Offset Voltage) OP OP OP OP / 2..2 (Input Bias Current) OP I B LM74 na OP pa 2..3 SR μs OP OP 0.5V/μs 2 [V] SR = Y [V/μs] X Y X [μs] 2: SR 2 2
X[μs] Y [V] SR SR = Y X [V=μs] 2..4 3(a) 3 3 0Hz 00 00000Hz 0 000kHz 000 0 /0 (GB ) f OP A = A f[hz] () GB OP OP OP 0Hz db0 5 db/dec db f T f T [Hz] (2) OP LM74 MHz 000000 3 3(b) R G ; R F f W f W GB 2..5 (Input Offset Current) (Differential Input Resistance) Differential Input Capacitance)Common Mode Rejection Ratio CMRR 2..6 db A G = [] A = [] 2 3
A V f v i V = v o =v i V v o V 00 RG R C R F 00k 0k k A = R F =R G v o V (a) (b) 0 5 0 4 0 3 0 2 A f = 00000 0000 000 A[] 00 0 jaj 0 0 2 0 3 0 4 0 5 0 6 f [Hz] (c) f T GB 0 0 00 000 0000 00000 e006 [Hz] (d) 3: OP A G dbdecibel G = 20 log A[dB] (3) = 20 log Vo [db] (4) db 4 db db log db db 0 20dB 00 =0 0 20dB 20dB = 40dB db db oct0 dec 6dB/oct 20dB/dec 0 0 2 4
: db p p [] /0 / 0 /2 / 2 p 2 2 p 0 0 00 000 0 000 00 000 000 000 [db] -20-0 -6-3 0 3 6 0 20 40 60 80 00 20 0 00 000 0 000 00 000 000000 db 0 20 40 60 80 00 20 4: db 2.2 OP OP 2.2. (Inverting amplifier circuit) 5 R R 2 OP. OP R 2 Imaginary Short 2. OP OP OP R 0V =R R 2 =R 2 OP G R R 2 =0 (5) G = = R 2 R (6) R R R 2 Z Z 2 R 2 R 5: 2 5
R R 2 6: 2.2.2 (Noninverting amplifier circuit) 6 G G = = R 2 R (7) OP 2.2.3 (Voltage Follower) 7 7 R R 2 0Ω db O P 7: 2.3 OP 2 6
2.3. (Differentiator) 8(a) j!c R =0 (8) (j!)= j!rc (j!) (9) j! (! =2ßf) j! s (t) = RC d(t) dt (0) R R C R i C (a) (b) 8: C R (0dB) (9) f = [Hz] () 2ßRC 2 /2 2 6dB/oct OP (GB ) -6dB/oct R i ( 8(b)) R i C R=R i f 2 = 2ßR i C [Hz] (2) f 2 OP (GB ) sin!t (9) d sin!t (t) = RC =!RC cos!t (3) dt 2 7
2.3.2 (Integrator) R C 9(a) (j!)= j!rc (j!) (4) =j! =s R f C C R - R - (a) (b) 9: (t) = RC Z (t)dt (5) 2 C /2 /2 6dB/oct OP A f f = 2ßARC [Hz] (6) 6dB/oct (0dB) f 3 f 3 = 2ßRC [Hz] (7) 9(b) f C R f f 2 f 2 = 2ßR f C [Hz] (8) f 2 f 3 f 2 R f =R 0 T = T T 2 ±V T V (5) (T ) (T )= RC V T (9) 2 8
V V T T 2 T =(RC) V T 2 =(RC) V T 0: : T 2 V (T 2 ) (T 2 )= RC V T 2 (20) 3 OP R R 4 INV.IN NON INV.IN 2 9
2 OUT IN OUT IN IN CH2 CH 2: 3. 3 OP 2 R 2 R INV. IN OUT R 4 3:. 0mV [khz] 0. 3 5 6 7 8 9 0 20 30 40 50 60 70 80 90 00 250 500 [V] [db] 2. khz 23 3. db 2 0
3.2 4 OP R 2 - NONINV. IN R 3 OUT R 4:. 00mV [khz] 0. 3 5 6 7 8 9 0 20 30 40 50 60 70 80 90 00 250 500 [V] [db] 2. khz 23 3. db 3.3 5 R 2 R C 0kΩ INV. IN 00Ω 0.μF OUT R 4 00Ω 5:. 500Hz V 2. 23 3. 6kHz 20mV 2 2
R 2 MΩ C INV. IN R 0kΩ - 0.μF OUT R 4 0kΩ 6: 3.4 6 OP. 00Hz ±V 2. 23 4. 3. R kω R 4 R R 2 =0mV =V 2. 3.2 R kω R 3 R R 2 =00mV =V 3. 3. 3.2) 4. 3. 3.2) 5. 3. 3.2) GB 6. 3.3 0dB 7. 3.4 T [T 2 ] (T )[ (T 2 )] 8. 3.3 3.4 5. 7 2. CMRR 2 2
3. 4. 0 0 0 0 5% 0 0% 2 2 0 2 20% 3 3 0 3 4 4 0 4 5 5 0 5 6 6 0 6 7 7 0 7 2 8 8 0 8 9 9 0 9 [] J. Graeme, G. Tobey, and L. Huelsman (Eds.): Operational Amplifiers, McGraw-Hill Book Company- Singapore (98). [2] 2004 2 3