AN-669: 有效地使用AD628精密增益模块 (Rev. 0)

AN-669
ᆌᆩԴऻ
One Technology Way t P.O. Box 9106 t Norwood, MA 02062-9106 t Tel: 781/329-4700 t Fax: 781/326-8703 t www.analog.com
ᆶၳ‫ں‬๑ᆩAD628৛௢ሺᅮఇ੷
ፕኁǖMoshe Gerstenhaber ࢅ Charles Kitchin
०঻
AD628੗ᅜፕྺֶ‫ݴ‬/Բ૩‫ٷݣ‬ഗईኁᆅগӿۨ‫ڦ‬৛௢ሺᅮ
ఇ੷๑ᆩăAD628༬՚ኍ‫ܔ‬ఇຕገ࣑ഗ‫ڦ‬മ‫ۉ܋‬ୟܸย
ऺLj‫׉ݥ‬๢ࢇፕྺ๼෇Բ૩ࢅ࣐؋‫ٷݣ‬ഗ๑ᆩăፕྺֶ‫ݴ‬
‫ٷݣ‬ഗLj໲ీٗፌߛ‫ڟ‬±120 V‫ࠌٷڦ‬ఇ‫ۉ‬უዐ༵ൽၭ‫ֶڦ‬
‫ۉݴ‬უăፕྺᇨ‫ހ‬ጎ৛௢ሺᅮఇ੷LjAD628‫ڦ‬ᆅগ੗ᅜԥ
ӿۨഐઠ༵ࠃ੻‫ڦྷݔ‬৛ඓሺᅮLjኄᄣ໲੗ᅜ৊ႜߛ৛‫܈‬
ຕ਍֑णLjबࢭுᆶሺᅮईኁ฿ۙ೏ᅎă
AD628๑ᆩਨ‫ܔ‬ፌณ‫ྔڦ‬থഗॲăഄၭ႙MSOP‫ހ‬ጎ๟๨
‫ׇ‬ฉ༵ࠃኄၵࠀీ‫ڦ‬ഗॲዐ؅٫ፌၭ‫ڦ‬ăਏᆶߛሺᅮ৛‫܈‬
ࢅ‫گ‬೏ᅎ‫ڦ‬ཞ้LjAD628༵ࠃ‫ࠌڦߛ׉ݥ‬ఇᅞ዆Ljཚ‫׉‬ሞ1
kHz้ࠌఇᅞ዆Բ‫ٷ‬ᇀ90 dBLjሞ100 kHz้ࠌఇᅞ዆Բධԍ
‫׼‬ሞ60 dBă
AD628ᆶᅃ߲VREFᆅগᆩᇀྺ‫ۉڇ‬ᇸADC༵ࠃ኱ୁ)ዐक़‫ۉ‬
ೝ*ೋዃăሞኄዖᆌᆩዐLjV REF ᆅগ੗ᅜ०‫૶ںڇ‬থ‫ڟ‬
ADC‫ۉ੊֖ڦ‬უᆅগLjኄᄣ੗ᅜ৊ႜ‫ݛ‬Ս‫ڦ‬Բ୲๕߾ፕă
ྺ๊஺ᄲ๑ᆩሺᅮఇ੷ICǛ
ሞํा֪ଉ้Ⴔᄲٗሯำᇸዐ༵ൽෑ႑ࡽăฯ዁ሞ৊ႜֶ
‫֪ݴ‬ଉࢫLjߛࠌఇ‫ۉ‬უධঢ়‫؜׉‬၄ă‫׉‬ᆩ‫ڦ‬঴ਦ‫ݛ‬ӄ๟๑
ᆩሏ໙‫ٷݣ‬ഗLjईኁ߸ࡻ‫ݛڦ‬ӄ๟๑ᆩᅏ՗‫ٷݣ‬ഗLj඗ࢫ
ᆩ‫گ‬ཚ୳հഗই‫گ‬ԝৠሯำ‫ۉ‬ೝă
ኄዖ‫د‬ཥ‫ڦ݆ݛ‬ඍ‫ۅ‬ሞᇀ‫ݴ‬૬ሏ໙‫ٷݣ‬ഗ‫ۉ‬ୟ‫ࠌڦ‬ఇᅞ዆
ႠీডֶLj໲‫ڦ‬๼෇‫ۉ‬უ‫ྷݔ‬ᄺጺ๟ၭᇀ‫ۉ‬ᇸ‫ۉ‬უă‫ړ‬๑
ᆩֶ‫ݴ‬႑ࡽᇸ้Lj‫ڇ‬ႊೌIC‫ڦ‬ᅏ՗‫ٷݣ‬ഗ‫ۉ‬ୟ༵ࣷߛࠌఇ
ᅞ዆Ⴀీă඗ܸLjᅏ՗‫ٷݣ‬ഗփీᆌ޲႑ࡽᇸ‫ٷ‬ᇀ‫ۉ‬ᇸࠃ
‫ۉۉ‬უईኁ႑ࡽ۠ेሞߛࠌఇ‫ۉ‬უ‫ڦ‬൧઄ăଷྔLj๑ᆩྔ
և‫ڇ‬ሺᅮ‫ۉ‬ፆ‫ڦ‬ᅏ՗‫ٷݣ‬ഗࣷ٪ሞሺᅮ೏ᅎăፌࢫLj‫گ‬ཚ
୳հཚ‫׉‬Ⴔᄲ޹े‫܀ڦ‬૬ሏ໙‫ٷݣ‬ഗतഄ໲ᅃၵྔথഗ
ॲăኄࣷၩࡼԐࡍ‫ۉڦ‬ୟӱ੣क़ă
ਏᆶԲ૩‫ٷݣ‬ഗࠀీ‫ڦ‬AD628ၩ‫أ‬କሞ‫ߌد‬ഗĂ‫ۉୁݴ‬ፆ
ईኁഄ໲ຕ਍֑ण‫ۅ‬ᅜतADCኮक़‫ڦ‬ኄၵ‫׉‬९࿚༶ă໲‫ڦ‬
ፌ‫ٷ‬120V‫ڦ‬๼෇‫ྷݔ‬ሎႹ኱থ֪ଉ‫ٷ‬႑ࡽईኁ۠ेሞ‫ࠌٷ‬
ఇ‫ۉ‬უฉ‫ڦ‬ၭ႑ࡽă
ਏᆶ‫ڇ‬ट‫گۅ‬ཚ୳հഗ‫ڦ‬Քጚֶ‫ݴ‬๼෇ADC࣐؋
ഗ‫ۉ‬ୟ
ස཮1໯๖LjAD628૶থ‫ڟ‬ᅃ߲۠ेሞ‫ࠌڦߛ׉ݥ‬ఇ‫ۉ‬უฉ
‫ݴֶڦ‬๼෇႑ࡽăAD628ሺᅮఇ੷ਏᆶଇ߲ాև‫ٷݣ‬ഗă
A1ࢅA2ăᆅগ3থ‫้ں‬Ljሏ໙‫ٷݣ‬ഗA1‫ڦ‬ሺᅮ๟0.1ă100 k
Ω๼෇‫ۉ‬ፆࢅഄ໲‫ݛ‬௬‫ڦ‬ยऺԍኤAD628ీࠕ‫ت‬૙۠ेሞ
ፌߛ±120 V‫ࠌڦ‬ఇ‫ۉ‬უฉ‫ڦ‬ၭ๼෇႑ࡽă
A1‫ڦ‬๼‫؜‬ཚࡗᅃ߲10 kΩ‫ۉ‬ፆথ‫ٷݣڟ‬ഗA2‫ڦ‬ኟ๼෇‫܋‬ă
ᆅগ4੗ᅜথᅃ߲ྔև‫ۉ‬ඹ‫ڟ‬ኄᅃ‫ۅ‬Ljኄᄣํ၄କ‫ڇ‬ट‫گ‬
ཚ୳հă
߀Վ๼‫؜‬Բ૩ᅺጱ
ස཮1໯๖Ljཚࡗ߀Վ‫ٷݣ‬ഗA2‫ڦ‬ሺᅮ੗ᅜยዃAD628‫ڦ‬
๼‫؜‬Բ૩ᅺጱăኄ߲‫ݥ‬ጆᆩሏ໙‫ٷݣ‬ഗ੗ᅜሞ‫ٷ‬ᇀ‫ڇ‬࿋ሺ
ᅮ‫ڦ‬ඪࢆሺᅮኵူ߾ፕăAD628੗ᅜยዃٗ0.1‫ڟ‬1000‫ۉڦ‬
ୟሺᅮă
Rev. 0 | Page 1 of 8
AN-669
C1
+15V
0.1 μ F
C FILTER
4
+VS
10kΩ
DIFFERENTIAL
INPUT SIGNAL
100k Ω
8
AD628
– IN
10kΩ
A1
V IN
100k Ω
1
A2
RG
V REF
2
5
– IN
10kΩ
–V S
V OUT
TO ADC
+ IN
+ IN
V CM
7
3
6
0.1 μF
RF
RG
–15V
཮1. ਏᆶ‫ڇ‬ट‫گۅ‬ཚ୳հഗ‫ڦ‬एԨֶ‫ݴ‬๼෇૶থ
ᆯᇀA1‫ڦ‬ሺᅮ๟0.1LjA1ᇑA2‫ڦ‬ፇࢇሺᅮ‫ڪ‬ᇀǖ
‫؜‬႑ࡽᅜADC๼෇‫ڦྷݔ‬ዐक़‫ྺۅ‬ዐ႐ă໚඗཮1ฉ๟
±15 VLj‫ڍ‬๟‫ۉ‬ୟ੗ᅜሞ±2.25 V‫ڟ‬±18 V‫ڦాྷݔ‬ມ‫ۉ‬ᇸࠃ
‫߾ူۉ‬ፕăኄ߲VREFᆅগᄺ੗ᅜᆩᇀ‫ۉڇ‬ᇸ߾ፕǗVREF੗
ᅜೋዃྺVS/2ă
VOUT
= G = 0.1(1 + (RF / RG ))
VIN
໯ᅜǖ
(10G-1) =
ᆩᅃ߲ྔথ‫ۉ‬ፆඟAD628‫ڦ‬ሺᅮၭᇀ0.1
RF
ස཮2໯๖LjAD628ሺᅮఇ੷‫ڦ‬ሺᅮ੗ᅜۙኝ‫ڟ‬0.01‫ڟ‬0.1ኮ
क़‫ڦ‬ඪᅪኵă
RG
ኄ߲૶থ‫ݛ‬๕ᇑ཮1‫੻ڦ‬๼෇‫ۉྷݔ‬ୟᅃᄣLjኻ๟ᆅগ5ᇑ
ᆅগ6ӿۨLjᆅগ4ཚࡗྔথ‫ۉ‬ፆRGথ‫ں‬ăᆅগӿۨ๑‫ٷݣ‬
ഗA2߾ፕሞ‫ڇ‬࿋ሺᅮူă‫ۉ‬ፆRGAINᇑA1๼‫ాೌڦ܋؜‬10
kΩ‫ۉ‬ፆࠌཞፇ‫ׯ‬ᅃ߲‫ݴ‬უഗLjᆩᅜປ३A1๼‫܋؜‬ᇑA2๼
෇‫܋‬ኮक़‫ڦ‬႑ࡽăኄዖ૶থ‫ݛ‬๕‫ڦ‬ሺᅮ‫ڪ‬ᇀ0.1 VIN ((10 kΩ
+ RG)/RG)ă
‫ܔ‬ᇀADC࣐؋‫ڦ‬ᆌᆩLjA2‫ڦ‬ሺᅮᆌ޿๑ADC‫ڦ‬ൻ‫ۉۯ‬უথ
ৎ஢ଉ‫ڦײ‬๼෇‫ྷݔ‬ăཚࡗྔথ‫ۉ‬ፆRFࢅRGยዃ๼‫؜‬Բ
૩ᅺጱ)नA2‫ڦ‬ሺᅮ*ࣷ๑ኄၵ‫ۉ‬ፆጲว‫ڦ‬ሺᅮ৛‫ࢅ܈‬೏ᅎ
ႠీՎֶă
‫܀‬૬‫ڦ‬VREFᆅগ੗ᅜྺAD628‫ڦ‬๼‫؜‬႑ࡽ༵ࠃೋዃLj๑๼
RG
+15V
0.1 μF
C FILTER
7
4
+VS
10kΩ
DIFFERENTIAL
INPUT SIGNAL
8
100k Ω
AD628
– IN
10kΩ
A1
V IN
1
100k Ω
+ IN
A2
– IN
10kΩ
V CM
–V S
2
V REF
3
RG
6
0.1 μF
–15V
཮2. ሺᅮၭᇀ0.1้AD628‫૶ڦ‬থ
Rev. 0 | Page 2 of 8
V OUT
TO ADC
+ IN
5
AN-669
+15V
C1
0.1 μF
0.1 μF
C FILTER
7
4
+V S
10kΩ
DIFFERENTIAL
INPUT SIGNAL
8
V IN
1
AD628
100k Ω
–
IN
10kΩ
A1
100k Ω
+
5
A2
IN
–
10kΩ
V CM
V OUT
TO ADC
+ IN
–V S
2
3
IN
RG
V REF
6
0.1 μ F
C2
RG
–15V
RF
཮3. ມट‫گۅ‬ཚ୳հֶ‫ݴ‬๼෇‫ۉ‬ୟ
ມट‫گۅ‬ཚ୳հ‫ݴֶڦ‬๼෇‫ۉ‬ୟ
཮3ዐ‫ۉڦ‬ୟ๟ᆩएԨ‫ڦ‬ADCথ੨‫ۉ‬ୟՎࣅܸઠ‫ڦ‬ăኄ
૛Ljມट‫گۅ‬ཚ୳հཚࡗᅃ߲޹े‫ۉ‬ඹ(C2)ํ၄ă
ၟኮമ‫ۉڦ‬ୟᅃᄣLj‫گ‬ཚ୳հഗ‫ڼڦ‬ᅃट‫ۅ‬๟ཚࡗA1๼‫؜‬
‫ాڦ܋‬և10 kΩ‫ۉ‬ፆࢅྔև‫ۉ‬ඹC1ํ၄‫ڦ‬ă‫ܾڼ‬ट‫ۅ‬๟ཚ
ࡗሞA2‫ݒ‬ઍ࣮ୟฉ‫ڦ‬ᅃ߲ྔևRC้क़‫׉‬ຕํ၄‫ڦ‬Lj໲ᆯ
ժ૴‫ۉڦ‬ፆRFࢅ‫ۉ‬ඹC2ፇ‫ׯ‬ă൩ጀᅪLjᇑ‫ڇ‬ट‫گۅ‬ཚ୳հ
ഗ၎ԲLj‫ܾڼ‬ट‫ీۅ‬๑‫ٷ‬ᇀRCገችೕ୲(1/(2πRC))‫ڦ‬ೕ୲
߸ტ໏‫ࡐں‬ইă඗ܸLjໜጣ๼෇ೕ୲‫ڦ‬ሺेLj‫ٷݣ‬ഗA2‫ڦ‬
ሺᅮፌዕই‫ڇڟگ‬࿋ኵժ൐փࣷም৊ᅃօ३ၭă໯ᅜLj
ሞೕ୲‫گ‬ᇀ໲‫–ڦ‬3 dBገች‫้ۅ‬Lj‫ٷݣ‬ഗA2‫ۉڦ‬უሺᅮᆯ
RF/RG‫ڦ‬Բ૩ਦۨLj໲ሞ߸ߛ‫ڦ‬ೕ୲้ྺ‫ڇ‬࿋ሺᅮă
10.0
OUTPUTVOLTAGE (V p-p)
RT = 49.9kΩ, RG = 12.4kΩ
C1 = 0.047μF, C2 = 0.01μF
཮4๟200 Hz –3 dBገችೕ୲‫୳ڦ‬հഗ๼‫؜‬ᇑೕ୲‫࠲ڦ‬ဣă
ٗገችೕ୲‫ٷڟ‬ሀ10Ԡገችೕ୲‫ాྷݔڦ‬ᆶ‫׉ݥ‬۸ോ‫ࡐڦ‬
ইăሞኄ߲ೕ୲‫ۅ‬ᅜฉLj‫ܾڼ‬ट‫ۅ‬փምᆶၳLjປ३୲ᇑ‫ڇ‬
ट‫ۅ‬ၚᆌথৎă
՗I
ມट‫گۅ‬ཚ୳հഗ
๼෇‫ྷݔ‬ǖ 10 V p-p F.S (5 V p-p๼‫)؜‬
RF = 49.9 kΩ, RG = 12.4 kΩ
–3 dBገችೕ୲
‫ۉ‬ඹ C2
‫ۉ‬ඹ C1
200 Hz
1 kHz
5 kHz
10 kHz
0.01 μF
0.047 μF
0.002 μF
0.01 μF
390 pF
0.002 μF
220 pF
0.001 μF
՗ II
ມट‫گۅ‬ཚ୳հഗ
๼෇‫ྷݔ‬ǖ20 V ‫ރރ‬ኵLj5V‫ރރ‬ኵ๼‫؜‬
RF = 24.3 kΩ, RG = 16.2 kΩ
–3 dBገችೕ୲
1.0
‫ۉ‬ඹ C2
‫ۉ‬ඹ C1
0.1
0.01
10
100
1k
FREQUENCY (Hz)
10k
཮4. ມट‫گۅ‬ཚ୳հഗ‫ڦ‬ೕ୲ၚᆌ
100k
200 Hz
1 kHz
5 kHz
10 kHz
0.02 μF
0.047 μF
0.0039 μF
0.01 μF
820 pF
0.002 μF
390 pF
0.001 μF
՗IࢅII๟‫ۆ‬႙୳հഗ‫ܔ‬ᇀփཞ–3 dBገችೕ୲ࢅଇ߲փཞ஢
ଉ‫ڦྷݔײ‬ഗॲ֖ຕኵă֖ຕኵᅙঢ়ԥ຺ป࿵෇ྺՔጚ‫ۉ‬
ፆࢅ‫ۉ‬ඹኵă‫ۉ‬ඹC1ࢅC2ՂႷ๟ߛQኵ‫گڦ‬೏ᅎഗॲǗփ
ᄲᆩ‫ڪگ‬प༩ٍ‫ۉ‬ඹăྺକፌ‫ڦگ‬೏ᅎࢅፌࡻ‫ॺڦ‬૬้
क़Ljླྀ४๑ᆩߛ೗ዊNPO༩ٍĂ਋ḇԋఈई਋ḇԋఈ‫ۉ‬
ඹă
Rev. 0 | Page 3 of 8
AN-669
ᆩAD628‫ॺٲ‬৛௢ሺᅮఇ੷
ํा‫ڦ‬ຕ਍֑णဣཥႴᄲӝෑ႑ࡽ‫ڟٷݣ‬ፁࠕ‫ٷ‬ժ༵ࠃߴ
ADCăփ႞‫ڦ‬๟Lj‫ړ‬ԥದዃ‫ׯ‬ሺᅮఇ੷้Lj‫ܠٷ‬ຕ೵ཚ‫ݣ‬
‫ٷ‬ഗ‫ۼ‬ᆶሺᅮဃֶࢅ฿ۙ೏ᅎă
ሞሏ໙‫ٷݣ‬ഗ‫ۉ‬ୟዐLjཚ‫ڦ׉‬ଇ߲‫ۉ‬ፆሺᅮยዃᆶ৛‫ࢅ܈‬
೏ᅎ‫ڦ‬၌዆ă‫ړ‬๑ᆩဃֶྺ1%‫ڦ‬Քጚ‫ۉ‬ፆ้Lj‫ٷݣ‬ഗ‫ڦ‬ሺ
ᅮࣷ३ณ2%ăᅺྺ௅߲‫ۉ‬ፆ‫ࣷۼ‬ᆶփཞ‫ڦ‬೏ᅎLjሺᅮᄺࣷ
ໜጣ࿒‫܈‬Վࣅă‫ۉೌڇ‬ፆྪஏ੗ᆩᇀ৛ඓ‫ڦ‬ሺᅮยዃLj‫ڍ‬
๟ኄၵഗॲሺेକ‫ׯ‬ԨLjްሗ‫ۉࢅ܈‬ୟӱ੣क़ă
཮5‫཮ڟ‬9‫ڦ‬ሺᅮఇ੷‫ۉ‬ୟਖ਼‫ޜ‬କ໯ᆶኄၵႠీฉ‫ڦ‬၌዆Lj
ᄺփ๟࢔ࡍLjժ൐๟‫ڇ‬MSOP‫ڦ‬঴ਦ‫ݛ‬ӄăAD628ᆩፌၭ
‫ڦ‬IC‫ހ‬ጎ༵ࠃକྜኝ‫ీࠀڦ‬ăᆯᇀ໯ᆶ‫ۉڦ‬ፆ‫ۼ‬ሞAD628
ሺᅮఇ੷ాևLj৛‫ࢅ܈‬೏ᅎኸՔ‫ࡻ׉ݥۼ‬ă
໯ᆶኄၵᆅগӿۨ‫ۉڦ‬ୟ)࿄๑ᆩྔথഗॲ*‫ۼ‬ᆶࡻᇀ0.2%
‫ڦ‬ሺᅮ৛‫܈‬Ljഄሺᅮ࿒‫܈‬ဣຕࡻᇀ50 ppm/°Că
AD628ፕྺ+10ई–10৛௢ሺᅮఇ੷
཮5๟AD628৛௢ሺᅮఇ੷IC༵ࠃ‫ۉ‬უሺᅮྺ+10‫ۉڦ‬ୟ૶
থăሺᅮఇ੷੗ᅜཚࡗᆅগӿۨईᆅগথ‫ں‬ઠದዃփཞ‫ڦ‬
ሺᅮăሺᅮఇ੷Ԩวᆯଇ߲ాև‫ٷݣ‬ഗፇ‫ׯ‬ǖᅃ߲ሺᅮྺ
0.1‫ ٷ ݣ ۯ ֶ ڦ‬ഗ (A1)त ࢫ ‫ ڦ ܋‬ᅃ ߲ ‫ ݥ‬ጆ ᆩ ࣐ ؋ ‫ ٷ ݣ‬ഗ
(A2)ă
๼෇႑ࡽথ‫ڟ‬VREFᆅগ(ᆅগ3)ࢅ‫ں‬ኮक़ă๼෇႑ࡽ૶থ‫ڟ‬
ᆅগ3้LjA1‫ڦ‬ኟ๼෇‫ۉڦ܋‬უ‫ڪ‬ᇀVIN (100 kΩ/110 kΩ)Lj
नVIN (10/11)ăᆅগ6থ‫้ں‬LjA2‫޶ڦ‬๼෇‫ڪ܋‬ᇀ0 Văᅺ
ُLjA2‫ڦ‬ኟ๼෇‫܋‬ᄺࣷԥઠጲA2๼‫ݒڦ܋؜‬ઍഽ዆ྺ
0 VăA1‫ڦ‬๼‫؜‬੝ۨᄺཞ้ྺ0 VăA1‫޶ڦ‬๼෇ՂႷ‫ڪ‬ᇀA1
‫ڦ‬ኟ๼෇Ljᄺ৽๟‫ڪۼ‬ᇀVIN (10/11)ă
ኄᅪ࿆ጣA2‫ڦ‬๼‫ۉ؜‬უ(VOUT)ྺǖ
VOUT = VIN (10/11)(1+100 k/10 k) =
VIN (10/11) 11 = 10 VIN
཮6ዐ‫ڦ‬ದ༫‫ۉ‬ୟ‫ڦ‬ሺᅮྺ–10ăኄْLj๼෇႑ࡽ૶থ‫ڟ‬A2
‫޶ڦ‬๼෇‫(܋‬ᆅগ6)ࢅ‫ں‬ă߾ፕᇱ૙๟ᅃᄣ‫ڦ‬Lj‫ڍ‬๟๼෇႑
ࡽԥA2‫݋‬ገକ180°ă‫ړ‬ᆅগ3থ‫้ں‬LjA1‫ڦ‬ኟ๼෇‫܋‬๟
0 VLjA1޶๼෇‫܋‬ᄺࣷԥ‫ݒ‬ઍ࣮ୟഽ዆ྺଭăᆯᇀA1‫ڦ‬ሺ
ᅮ๟1/10 (0.1)Lj ႴᄲA2‫ڦ‬๼‫޶ྺ؜‬10 VIN ഽ዆A1‫޶ڦ‬๼෇
‫ྺ܋‬0ă
ଇዖ૶থᆶփཞ‫ڦ‬๼෇ፆੇă‫ړ‬ൻ‫ۯ‬ᆅগ3้)཮5*Lj‫ںܔ‬
‫ڦ‬๼෇ፆੇ๟110 kΩLjܸൻ‫ۯ‬ᆅগ6้)཮6*Lj‫ںܔ‬๼෇ፆ
ੇ๟‫ٷ‬ሀ50 GΩăኄ߲‫ۉ‬ୟ‫–ڦ‬3 dB‫ܔ੻ټ‬ᇀ10mv๼෇႑ࡽ
‫ٷ‬ሀ๟110 kHzLj‫ܔ‬ᇀ100mV๼෇႑ࡽ‫ٷ‬ሀ๟95 kHză
+15V
0.1μ F
CFILTER
7
4
+VS
10kΩ
100kΩ
8
100kΩ
1
–
+
AD628
IN
A1
10kΩ
+ IN
A2
IN
– IN
10kΩ
–VS
2
3
VREF
RG
6
0.1μ F
–15V
VIN
཮5. ࿮ྔথഗॲሺᅮྺ+10‫ۉڦ‬ୟ
Rev. 0 | Page 4 of 8
5
VOUT
AN-669
+15V
0.1μF
CFILTER
7
4
+VS
10kΩ
100kΩ
8
100kΩ
1
AD628
– IN
10kΩ
A1
+
+ IN
IN
A2
5
– IN
10kΩ
–VS
2
3
RG
VREF
VOUT
6
0.1μF
–15V
VIN
཮6. ሺᅮྺ–10‫ڦ‬ದ༫‫ۉ‬ୟ
ᅪLjኄ߲‫ۉ૴ز‬ፆᇑ‫ٷݣ‬ഗA1‫ڦٷ׉ݥ‬๼෇ፆੇ၎Բ੗ᅜ
ࢮ୼փऺăٗᆅগ8‫ڟ‬A1๼‫ڦ܋؜‬ሺᅮ๟0.1ăᅺُLj‫ݒ‬ઍ
࣮ୟࣷഽ዆A2‫ڦ‬๼‫ڪ܋؜‬ᇀ10 VINăኄ߲‫ۉ‬ୟ‫–ڦ‬3 dB‫੻ټ‬
‫ܔ‬ᇀ10mv๼෇႑ࡽ‫ٷ‬ሀ๟105 kHzLj‫ܔ‬ᇀ100mV๼෇႑ࡽ‫ٷ‬
ሀ๟95 kHză
AD628‫ڦ‬৛௢ሺᅮยዃྺ+11
‫أ‬କᆅগ1ᇑᆅগ3ӿܸۨփ๟থ‫ں‬Ljሺᅮྺ+11‫ۉڦ‬ୟ)཮
7*बࢭᇑሺᅮྺ+10‫ۉڦ‬ୟ૶থ၎ཞăኄ๑૶থ‫ڟ‬A1‫ڦ‬ኟ
๼෇‫ڦ܋‬ଇ߲ాև‫ۉ‬ፆ(100 kΩ ࢅ 10 kΩ)ժ૴ഐઠă၄ሞᅎ
‫أ‬କVINᇑA1‫ڦ‬ኟ๼෇ኮक़‫ڦ‬10 kΩ/110 kΩ‫ݴ‬უഗăঢ়ࡗኄ
ᄣ‫ۙڦ‬ኝLjV INཚࡗ‫ٷ‬ሀ9 kΩ‫ۉڦ‬ፆൻ‫ۯ‬ኟ๼෇‫܋‬ă൩ጀ
7
4
CFILTER
+VS
10kΩ
8
1
100kΩ
100kΩ
AD628
– IN
10kΩ
A1
+
+ IN
IN
A2
– IN
10kΩ
–VS
2
3
VREF
RG
6
VIN
཮7. ሺᅮྺ+11‫ۉڦ‬ୟ
Rev. 0 | Page 5 of 8
5
VOUT
AN-669
AD628‫ڦ‬৛௢ሺᅮยዃྺ+1
ਏᆶമઍ‫ڦ‬ሺᅮྺ–9.91‫੻ټڦ‬કቛሺᅮఇ੷
཮8๟AD628༵ࠃ৛௢ሺᅮྺ+1‫ۉڦ‬ୟ૶থăᇑኮമᅃ
ᄣLjኄ߲‫ۉ‬ୟ૶থ๑ᆩሺᅮఇ੷ాև‫ۉڦ‬ፆྪஏઠइ‫ߛڥ‬
ሺᅮ৛‫ࢅ܈‬࿘ۨႠă
཮6ዐ‫ۉڦ‬ୟ੗ᅜฎྲႪ߀ཚࡗ๑ᆩณଉኟ‫ݒ‬ઍઠሺे໲
‫੻ټڦ‬Ljස཮9ăཚࡗӝᆅগ4ࢅᆅগ1૶থሞᅃഐLj‫ٷݣ‬
ഗA1‫ڦ‬๼‫؜‬മઍ‫ڟ‬໲‫ڦ‬ኟ๼෇‫܋‬ă၄ሞLjሺᅮ= –(10 –
1/11)= –9.91ă
๼෇႑ࡽ૶থ‫ڟ‬VREFᆅগࢅ‫ں‬ኮक़ăᆯᇀᆅগ1ࢅᆅগ8๟
থ‫ڦں‬Lj๼෇႑ࡽཚࡗ100 kΩ/110 kΩ‫ڦ‬๼෇ປ३ഗ๼෇‫ڟ‬
A1‫ڦ‬ኟ๼෇‫܋‬ă‫ۉ‬უ‫ڪ‬ᇀVIN (10/11) = 0.909 VINăٗኄ‫ۅ‬
‫ڟ‬A1๼෇‫ڦ܋‬ሺᅮ‫ڪ‬ᇀ1 + (10 kΩ/100 kΩ) = 1.10ăᅺُLj
A1๼‫ۉڦ܋؜‬უ‫ڪ‬ᇀVIN (1.10) (0.909) = 1.00ăA2‫ٷݣ‬ഗᅜ
‫ڇ‬࿋ሺᅮ࣐؋‫ݛ‬๕߾ፕ)ᅺྺᆅগ5ࢅᆅগ6૶থሞᅃഐ*Lj
ഄጺ‫ۉ‬ୟሺᅮྺ+1ă
Ⴊ߀ࢫ‫ۉڦ‬ୟධ඗࿘ۨLjᅺྺኝ߲‫ۉ‬ୟᆶକ‫ٷ‬ଉ‫ݒ޶ڦ‬ઍ
)ٗA2‫ڦ‬๼෇‫ڟ࣮܋‬A1‫޶ڦ‬๼෇‫*܋‬ăኄ߲‫ۉ‬ୟ૶থ‫ڦ‬ၭ႑
ࡽ–3 dB‫ٷ੻ټ‬ሀྺ140 kHzăኄԲ཮6ዐႪ߀മ‫ۉڦ‬ୟ‫ټڦ‬
੻ሺेକ27%ă඗ܸLjሺᅮ৛‫܈‬ই‫ڟگ‬କ±2%ă
+15V
CFILTER
7
4
+VS
10kΩ
100kΩ
8
1
AD628
– IN
10kΩ
A1
100kΩ
+ IN
+ IN
–
10kΩ
–VS
2
0.1μ F
VREF
3
VOUT
A2
IN
5
RG
6
0.1μ F
–15V
VIN
཮8. ৛௢ሺᅮྺ+1‫ڦ‬AD628‫ۉ‬ୟ
CFILTER
+VS
10kΩ
8
1
100kΩ
–
100kΩ
AD628
IN
10kΩ
A1
+
+ IN
IN
A2
– IN
10kΩ
–VS
2
7
4
3
VREF
RG
6
VIN
཮9. ਏᆶമઍ‫ۉ‬ୟ‫ڦ‬৛௢ሺᅮྺ–10‫ڦ‬ሺᅮఇ੷
Rev. 0 | Page 6 of 8
5
VOUT
AN-669
Rev. 0 | Page 7 of 8
AN-669
© 2003 Analog Devices, Inc. All rights reserved. Trademarks and registered
trademarks are the property of their respective companies.
E04332–0–7/03(0)
Rev. 0 | Page 8 of 8
Similar pages