Op Amp Applications Handbook Walt Jung, Editor

More documents

Recommendations

Info

GAIN (R1) 1.04Ω - 37.4Ω FEEDBACK RESISTOR (R2) (151kΩ) Adapted from: Stewart E. Miller, “Sensitive DC Amplifier with AC Operation,” Electronics, November 1941, pp. 27−31, 105−109 Figure 1-17: A 1941 vacuum tube feedback circuit using current feedback 6 dB / OCTAVE (20 dB / DECADE) SLOPE Adapted from: Stewart E. Miller, “Sensitive DC Amplifier with AC Operation,” Electronics, November 1941, pp. 27−31, 105−109 Figure 1-18: A 1941 feedback circuit shows characteristic CFB gain-bandwidth relationship 27 Op Amp Basics To clarify this point on bandwidth, a standard VFB op amp 6 dB/octave (20 dB/decade) slope has been added to Figure 1-18 for reference. Although there is no mention of the signifi cance of this within the text of the actual article, it nevertheless illustrates a popular application of CFB behavior, in the design of high speed programmable gain amplifi ers with relatively constant bandwidth.
Chapter One When transistor circuits ultimately replaced vacuum tube circuits between the late 1950s and the mid- 1960s, the current feedback architecture became popular for certain high speed op amps. Figure 1-19 shows a fast-settling op amp designed at Bell Labs in 1965, for use as a building block in high speed A/D converters (see Reference 5). V IN R1 TO DC SERVO AMP R2 Adapted from: J. O. Edson and H. H. Henning, “Broadband Codecs for an Experimental 224Mb/s PCM Terminal,” BSTJ, Vol. 44, No. 9, November 1965, pp. 1887−1950 Figure 1-19: A 1965 solid- state current feedback op amp design from Bell Labs The circuit shown is a composite amplifi er containing a high speed ac amplifi er (shown inside the dotted outline) and a separate dc servo amplifi er loop (not shown). The feedback resistor R2 is ac coupled to the low impedance emitter of transistor Q1. The circuit design was somewhat awkward because of the lack of good high frequency PNP transistors, and it also required zener diode level shifters, and nonstandard supplies. Hybrid circuit manufacturing technology, which was well established by the 1980s, allowed the use of fast, relatively well-matched NPN and PNP transistors, to realize CFB op amps. The Analog Devices’ AD9610 and AD9611 hybrids were good examples of these devices introduced in the mid-1980s. With the development of high speed complementary bipolar IC processes in the 1980s (see Reference 6) it became possible to realize completely dc-coupled current feedback op amps using PNP and NPN transistors such as the Analog Devices’ AD846, introduced in 1988 (Figure 1-15). Device matching and clever circuit design techniques give these modern IC CFB op amps excellent ac and dc performance without a requirement for separate level shifters, awkward supply voltages, or separate dc servo loops. Various patents have been issued for these types of designs (see References 7 and 8, for example), but it should be remembered that the fundamental concepts were established decades earlier. 28
Page 2 and 3: Op Amp Applications Handbook
Page 4 and 5: Op Amp Applications Handbook Walt J
Page 6 and 7: v Contents Foreword ...............
Page 8 and 9: vii Foreword The signal-processing
Page 10 and 11: ix Preface Op Amp Applications Hand
Page 12 and 13: xi Preface and diversity of use. Th
Page 14 and 15: Signal Amplifi ers; Audio Amplifi e
Page 16 and 17: 1928 Harold S. Black applies for pa
Page 18 and 19: CHAPTER 1 Op Amp Basics ■ Section
Page 20 and 21: CHAPTER 1 Op Amp Basics James Bryan
Page 22 and 23: As a precursor to more detailed sec
Page 24 and 25: INPUT 7 Op Amp Basics Note that wit
Page 26 and 27: Thus an ideal noninverting op amp s
Page 28 and 29: G2 V 2 V 1 R G ' OP AMP G = VOUT /V
Page 30 and 31: 13 Op Amp Basics It is important to
Page 32 and 33: dB A VOL β G CL Figure 1-7: Op amp
Page 34 and 35: Input Dynamic Range 17 Op Amp Basic
Page 36 and 37: 19 Op Amp Basics dual- supply devic
Page 38 and 39: References: Introduction 21 Op Amp
Page 40 and 41: The previous section examined op am
Page 42 and 43: 25 Op Amp Basics The CFB topology i
Page 46 and 47: References: Op Amp Topologies 29 Op
Page 48 and 49: This section describes op amps in t
Page 50 and 51: Single Supply Offers: − Lower Pow
Page 52 and 53: +VS 7 (−) 2 INPUTS 3 (+) −VS 4
Page 54 and 55: 37 Op Amp Basics has a maximum inpu
Page 56 and 57: Offset as Low as 50µV Offset TC ~
Page 58 and 59: +VS (+) INPUTS (−) −V S J1 I1 V
Page 60 and 61: (A) (B) (C) +VS +VS NPN NPN -V S V
Page 62 and 63: Figure 1-33: AD8531/AD8532/AD8534 C
Page 64 and 65: 47 Op Amp Basics a device, even wit
Page 66 and 67: BIPOLAR (NPN-BASED): This is Where
Page 68 and 69: Most op amp specifi cations are lar
Page 70 and 71: Figure 1-39: Alternate input offset
Page 72 and 73: Figure 1-42: Noninverting op amp ex
Page 74 and 75: 57 Op Amp Basics Extremely low inpu
Page 76 and 77: Input Impedance Figure 1-48: Input
Page 78 and 79: 61 Op Amp Basics Some fast op amps
Page 80 and 81: ±10V RAMP 10kΩ 10kΩ V OS -VREF
Page 82 and 83: 65 Op Amp Basics This sine wave sig
Page 84 and 85: V 1 R1 − + Figure 1-56: Measuring
Page 86 and 87: GAIN dB OPEN LOOP GAIN, A(s) IF GAI
Page 88 and 89: GAIN dB G1 G2 Figure 1-62: Frequenc
Page 90 and 91: Figure 1-65: Johnson noise of resis
Page 92 and 93: 100 10 795 743 NOISE n/√Hz or µV
Page 94 and 95:
20nV/div. (RTI) + 100 90 .... ....
Page 96 and 97:
Nominal Peak-to-Peak 2 × rms 3 ×
Page 98 and 99:
B A V N,R1 ∼ 4kTR1 V N,R3 ∼ 4kT
Page 100 and 101:
V s = Signal Amplitude (RMS Volts)
Page 102 and 103:
85 Op Amp Basics Note inverting mod
Page 104 and 105:
Power Supplies and Decoupling 87 Op
Page 106 and 107:
This section examines in more detai
Page 108 and 109:
91 Op Amp Basics Note that the offs
Page 110 and 111:
93 Op Amp Basics the nulling amplif
Page 112 and 113:
Noise Considerations for Chopper-St
Page 114 and 115:
Introduction High speed analog sign
Page 116 and 117:
99 Op Amp Basics voltage, v, into a
Page 118 and 119:
g 1 f = = = 153MHz u m 2 CP 2 520 1
Page 120 and 121:
v in R1 + v − − gm + I T i = v
Page 122 and 123:
+V S − −VS Q1 Q3 Q5 Q2 Q4 Q6 Fi
Page 124 and 125:
107 Op Amp Basics Note also that th
Page 126 and 127:
Q1 + − Q2 I1 I2 Figure 1-110: Sim
Page 128 and 129:
R1 C2 A − R2 B |A(s)| VFB OP AMP
Page 130 and 131:
High Speed Current-to-Voltage Conve
Page 132 and 133:
4mA C1 20pF 500Ω − VFB 1 fp = =
Page 134 and 135:
Voltage Feedback Op Amps: − Volta
Page 136 and 137:
CHAPTER 2 Specialty Amplifi ers ■
Page 138 and 139:
CHAPTER 2 Specialty Amplifi ers Wal
Page 140 and 141:
Probably the most popular among all
Page 142 and 143:
125 Specialty Amplifi ers buffers i
Page 144 and 145:
127 Specialty Amplifi ers balanced
Page 146 and 147:
129 Specialty Amplifi ers When dual
Page 148 and 149:
V1 (-) 100kΩ V REF + 25kΩ 25k
Page 150 and 151:
-IN ~ 400Ω V CM + VSIG ~ 2 _ + VS
Page 152 and 153:
135 Specialty Amplifi ers The gener
Page 154 and 155:
In Amp DC Error Sources 137 Special
Page 156 and 157:
Figure 2-20: AD620 In amp common-mo
Page 158 and 159:
141 Specialty Amplifi ers summed in
Page 160 and 161:
AD524C AD620B AD621B 1 AD622 AD624C
Page 162 and 163:
R+∆R R-∆R V B R-∆R R G R+∆R
Page 164 and 165:
147 Specialty Amplifi ers A factor
Page 166 and 167:
149 Specialty Amplifi ers Classic C
Page 168 and 169:
Most data acquisition systems with
Page 170 and 171:
153 Specialty Amplifi ers To unders
Page 172 and 173:
Low Noise PGA 155 Specialty Amplifi
Page 174 and 175:
157 Specialty Amplifi ers The OP113
Page 176 and 177:
159 Specialty Amplifi ers Since tra
Page 178 and 179:
Analog Isolation Techniques There a
Page 180 and 181:
163 Specialty Amplifi ers An isolat
Page 182 and 183:
Figure 2-51: AD215 120kHz low disto
Page 184 and 185:
167 Specialty Amplifi ers This prod
Page 186 and 187:
References: Isolation Amplifi ers 1
Page 188 and 189:
CHAPTER 3 Using Op Amps with Data C
Page 190 and 191:
CHAPTER 3 Using Op Amps with Data C
Page 192 and 193:
175 Using Op Amps with Data Convert
Page 194 and 195:
References: Introduction 177 Using
Page 196 and 197:
ADC and DAC Static Transfer Functio
Page 198 and 199:
Page 200 and 201:
ADC Input-Referred Noise 183 Using
Page 202 and 203:
75Ω 185 Using Op Amps with Data C
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Introduction Op amps are often used
Page 212 and 213:
Input Common-Mode Voltage Range Out
Page 214 and 215:
~ R EXT V SOURCE R INT 7kΩ SWITCH
Page 216 and 217:
~ R S V S REFOUT/ REFIN V INX R1 2k
Page 218 and 219:
Driving CMOS ADCs with Switched Cap
Page 220 and 221:
V IN + - Figure 3-35: Optimizing si
Page 222 and 223:
INPUT ±1V 1kΩ + 10µF Drivers fo
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
This page intentionally left blank
show all

Op Amp Applications Handbook Walt Jung, Editor

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?