View ADA4627-1ARZ_7039248.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

3 0 v, high speed , low noise, low bias current, jfet operational amplifier ada4627 - 1/ada4637 - 1 rev. d information furnished by analog devices is believed to be accurate and reliable. however, no responsibility is assumed by analog devices for its use, nor for any infringements of patents or other rights of third parties that may r esult from its use. specifications subject to change without notice. no license is granted by implication or otherwise under any patent or patent rights of analog devices. trademarks and registered trademarks are the property of their respective owners. one technology way, p.o. box 9106, norwood, ma 02062 - 9106, u.s.a. tel: 781.329.4700 www.analog.com fax: 781.461.3113 ? 2009 - 2010 analog devices, inc. all rights reserved. f eatures low offset voltage: 2 00 v maximum offset d rift: 1 v/ c typical very low input bias cu rrent: 5 pa maximum extended t emperature range: ? 40 c to +125 c 5 v to 1 5 v dual supply ada4627 - 1 gbw : 1 9 mhz ada4637 - 1 gbw: 79 mhz voltage noise: 6.1 nv/ hz at 1 khz ada4627 - 1 slew rate: 82 v / s ada4637 - 1 slew rate: 170 v/ s high g ain: 1 20 db typical high cmrr: 1 1 6 db typical high psrr: 1 1 2 db typical a pplications high i mpedance sens ors photo diode a m plifier precision in strumentation phase - locked l oop f ilters h igh end, professional a udio dac output amplifier ate medical p in c onfigurations null 1 ?in 2 +in 3 v? 4 nc 8 v+ 7 out 6 null 5 nc = no connect ada4627-1 t op view (not to scale) 07559-001 figure 1. 8- lead soic_n (r - 8) null 1 ?in 2 +in 3 v? 4 nc 8 v+ 7 out 6 null 5 nc = no connect ada4637-1 t op view (not to scale) 07559-103 figure 2. 8- lead soic_n (r - 8) pin 1 indic a t or notes 1. nc = no connec t . 2. it is recommended th a t the exposed p ad be connected t o v?. 1 nc 2 ?in 3 +in 4 v? 7 v+ 8 nc 6 out 5 nc t op view (not toscale) ada4627-1/ ada4637-1 07559-002 figure 3. 8- lead lfcsp _vd (cp - 8 - 2) general description the ada4627 - 1/ada4637 - 1 are wide bandwidth precis i on amplifier s featuring low noise, very low offset, drift, and bias current. the parts o perat e from 5 v to 15 v dual supply . the ada4627 - 1/ada4637 - 1 provide benefits previousl y found in few amplifiers. the s e amplifier s combine the best specifications of precision dc and high speed ac op amps . the ada4637 - 1 is a decompensated version of the ada4627 - 1 and is stable at a noise gain of 5 or greater. with a typical offset voltage o f only 70 v, drift of less than 1 v/c, and noise of only 0.86 v p - p (0 .1 hz to 10 hz), the ada4627 - 1/ada4637 - 1 are suited for applications where error sources cannot be tolerated. the ada4627 - 1/ada4637 - 1 are specified for both the industrial temperatu re range of ? 25 c to + 8 5c and the extended industrial temperature range of ?40c to +125c . the ada4627 - 1 / ada4637 - 1 are available in tiny 8 - lead lfcsp and 8 - lead soic packages . the ada4627 - 1/ada4637 - 1 are member s of a growing series of high speed, precision op amps offered by analog devices , inc . (see table 1 ). table 1 . high speed precision op amps supply 5 v low cost 5 v 26 v low power 30 v low cost 30 v single ad8615 ad8651 ad8610 ad8510 ada4627 - 1/ada4637 - 1 dual ad8616 ad8652 ad8620 ad8512 quad ad8618 ad8513
ada4627- 1/ada4637 - 1 rev. d | page 2 of 20 table of contents features .............................................................................................. 1 applications ....................................................................................... 1 pin configurations ........................................................................... 1 general description ......................................................................... 1 revision history ............................................................................... 2 specifications ..................................................................................... 3 electrical characteristics 30 v operation ............................. 3 absolute maximum ratings ............................................................ 5 thermal resistance ...................................................................... 5 esd caution .................................................................................. 5 typical performance characteristics ............................................. 6 theory of operation ...................................................................... 14 input voltage range ................................................................... 14 input offset voltage adjust range ........................................... 14 input bias current ...................................................................... 14 noise considerations ................................................................. 14 thd + n measurements ........................................................... 15 printed circuit board layout, bias current, and bypassing 15 output phase reversal ............................................................... 15 decompen sated op amps ........................................................ 16 driving capacitive loads .......................................................... 16 outline dimensions ....................................................................... 17 ordering guide .......................................................................... 18 revision history 10/10 rev. c to rev. d changes to figure 1 and general description .............................. 1 change s to ordering guide .......................................................... 18 7 /10 rev. b to rev. c add ed ada4637 - 1 ............................................................. universal added figure 2; renumbe red sequentially .................................. 1 changes to table 2 ............................................................................ 3 change to table 3 ............................................................................. 5 changes to t ypical performance characteristics section ........... 6 updated outline dimensions ....................................................... 17 changes to ordering guide .......................................................... 18 10/0 9 rev. a to rev. b changes to figure 2 ........................................................................... 1 9 /0 9 rev. 0 to rev. a changes to ge neral description section ....................................... 1 changes to table 2 ............................................................................. 3 updated outline dimensions ....................................................... 14 changes to ordering guide .......................................................... 15 7/09 revision 0: initial version
ada4627- 1/ada4637 - 1 rev. d | page 3 of 20 specifications electrical character istics 30 v operation v s y = 1 5 v, v cm = 0 v , t a = 25 c, unless otherwis e noted. table 2 . b grade a grade parameter symbol test conditions /comments min typ max min typ max unit input characteristics offset voltage 1 v os 70 200 120 300 v ?40 c t a +85 c 350 4 1 0 v ?40 c t a +125 c 400 6 6 0 v offset voltage drift , a verage ? v os / ? t ?40 c t a +125 c 1 2 1 3 v/ c power supply rejection ratio psrr v sy = 4.5 v to 18 v 106 112 103 108 db ?40 c t a +125 c 101 9 9 db input bias current 2 i b 1 5 1 5 pa ?40c t a +85c 0.5 0.5 na ?40c t a +125c 2 2 na input offset current i os 0.5 5 0.5 5 pa ?40c t a +85c 0.5 0.5 na ?40c t a +125c 2 2 na noise performance voltage noise density e n f = 10 hz 16.5 4 0 16.5 40 nv/ hz f = 100 hz 7.9 20 7.9 20 nv/ hz f = 1 khz 6.1 8 6.1 8 nv/ hz f = 10 khz 4.8 6 4.8 6 nv/ hz voltage noise e n p - p 0.1 hz to 10 hz 0. 7 1.6 0. 7 1.6 v p - p current noise density i n f = 100 hz 1.6 2.5 fa/ hz current nois e i n p - p 0.1 hz to 10 hz 30 48 fa p - p input resistance r in 10 10 t ? input capacitance, differential mode c indm 8 8 pf input capacitance, common mode c incm 7 7 pf input voltage range ivr ?11 +11 ?11 +11 v ?40 c t a +125 c ?10 .5 +10.5 ?10.5 +10.5 v common - mode rejection ratio cmrr t a = 25 c, v cm = ?11 v to +11 v 106 116 100 110 db ?40 c t a +125 c, 98 97 v cm = ?1 0.5 v to +1 0.5 v db large signal voltage gain a vo r l = 1 k ? , v o = ?10 v to +10 v 112 120 106 120 db ?40 t a +85c 110 104 db ?40 t a +125c 102 100 db dynamic performance slew rate ada4627 - 1 sr 10 v step, r l = 1 k ?, c l = 100 pf, a v = +1 40 56/78 3 40 56/78 3 v/s sr 10 v step, r l = 1 k ?, c l = 100 pf , r s = r f = 1 k ? , a v = ?1 40 82/84 3 40 82/84 3 v/s slew rate ada4637 - 1 sr 10 v out , c f = 4.8 pf, a v = ? 4 170 170 v/s sr 10 v out , c f = 4.8 pf, a v = +5 170 170 v/s
ada4627- 1/ada4637 - 1 rev. d | page 4 of 20 b grade a grade parameter symbol test conditions /comments min typ max min typ max unit settling time to 0.01% t s ada4627 - 1 v in = 10 v step, c l = 35 pf, r l = + 1 k ? , a v = ?1 550 550 ns ada4637 - 1 v in = 10 v step, c l = 35 pf, r l = + 1 k ? , a v = ? 4 300 300 n s settling time to 0.1% t s ada4627 - 1 v in = 10 v step, c l = 35 pf, r l = + 1 k ? , a v = ?1 450 450 ns ada4637 - 1 v out = 10 v step, c l = 35 pf, r l = + 1 k ? , a v = ? 4 200 200 ns gain bandwidth product gbp ada4627 - 1 r l = 1 k ?, c l = 2 0 pf, a v = 1 16 4 19 16 4 19 mhz ada4637 - 1 a v = 10 79.9 79.9 phase margin m ada4627 - 1 r l = 1 k ?, c l = 20 pf, a v = 1 72 72 degrees ada4637 - 1 a v = 10 85 85 total harmonic distortio n + noise thd + n f = 1 khz, a v = 1 , ada4627 - 1 0.000045 0.000045 % power supply supply current per amplifier i sy i o = 0 ma 7.0 7.5 7.0 7.5 ma ?40 c t a +125 c 7.8 7.8 ma output characteristics output voltage high v oh r l = 1 k ? to v cm 12.0 12.3 12.0 12.3 v ?40 c t a +85 c 11.8 11.8 v ?40 c t a +125 c 11.7 11.7 v output voltage low v ol r l = 1 k ? to v cm ?12.7 ?12.3 ?12 .7 ? 12.3 v ?40 c t a +85 c ?12.1 ? 12.1 v ?40 c t a +125 c ?12.0 ? 12.0 v output current i out v o = 10 v 45 45 ma short - circuit current i sc t a = 25 c +70/ ?55 +70/ ?55 ma closed - loop output impedance z out f = 1 mhz, a v = ?100 41 41 ? 1 v os is measured fully warmed up. 2 tested/extrapolated from 125 c . 3 rising/falling. 4 not tested. guaranteed by simulation and characterization.
ada4627- 1/ada4637 - 1 rev. d | page 5 of 20 absolute maximum rat ings table 3 . p arameter rating supply voltage 36 v input voltage range 1 ( v ?) ? 0.3 v to ( v +) + 0.3 v input current 1 10 ma differential input voltage 2 v sy output short - circuit duration to gnd indefinite storage temperature range ? 65 c to +150 c operating tempera ture range ? 40 c to + 125 c junction temperature range ? 65 c to +150 c lead temperature (soldering, 60 sec) 300 c esd h uman body model 4 kv 1 input pin has clamp diodes to the power supply pin s . input current should be limited to 10 ma or less whenever input signals exceed the power supply rail by 0. 3 v . 2 differential input voltage is limited to 30 v or the supply voltage, whichever is less. stresses above those listed under absolute maximum ratings may cause permanent damage to the device. this is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect d evice reliability. thermal resistance ja is specified for the worst - case conditions, that is, a device soldered in a circuit board for surface - mount packages. this was measured using a standard 2 - layer board. for the lfcsp package, the exposed pad should be soldered to a copper plane. table 4 . thermal resistance package type ja jc unit 8 - lead soic_n (r -8) 1 55 4 5 c/w 8 - lead lfcsp ( cp -8 -2 ) 77 14 c/w esd caution
ada4627- 1/ada4637 - 1 rev. d | page 6 of 20 typical performance characteristics t a = 25 c, unless o therwise noted. 1 10 100 0.01 0.1 1 10 frequency (khz) voltage noise density (nv/ hz) ada4627-1 t a = 25c v sy = 15v 07559-003 figure 4 . voltage noise density vs. frequency 60 80 100 120 140 ?50 ?25 0 25 50 75 100 125 temperature (c) open-loop gain (db) r l = 1k ? r l = 600 ? ada4627-1 t a = 25c v sy = 15v v o = 11v 07559-004 figure 5 . open - loop gain vs. temperature 12 0 1 00 80 60 40 2 0 0 100 1k 1 0k 10 0k 1 m 10 m fr e qu e ncy (h z ) cmrr (db) ada4627-1 t a = 25c v sy = 15v 07559-010 figure 6 . cmrr vs. frequency ?40 ?20 0 20 40 60 80 100 120 1k 10k 100k 1m 10m 100m frequency (hz) gain (db) and phase (degrees) ada4627-1 t a = 25c v sy = 15v 07559-006 19.1mhz 78 figure 7 . open - loop gain and phase vs. frequency 0.01 0.1 1 10 100 100 1k 10k 100k 1m 10m 100m frequency (hz) z out (?) a v = ?100 a v = ?10 a v = ?1 ada4627-1 t a = 25c v sy = 15v 07559-007 figure 8 . closed - loop z out vs. frequency 150 100 50 0 ?50 ?100 ?150 ?15 ?10 ?5 0 5 10 15 v os (v) v cm (v) ada4627-1 t a = 25c v sy = 15v 07559-069 figure 9. v os vs. common - mode voltage
ada4627- 1/ada4637 - 1 rev. d | page 7 of 20 0 20 40 60 80 100 120 100 1k 10k 100k 1m 10m frequency (hz) psrr (db) psrr+ psrr? ada4627-1 t a = 25c v sy = 15v 07559-009 figure 10 . psrr vs. frequency 0 1 2 3 4 5 6 7 8 0 4 8 12 16 20 24 28 32 36 supply voltage (v) supply current (ma) +125oc +85oc +25oc ?40oc 07559-011 ada4627-1 figure 11 . supply current vs. supply voltage and temperature 100 1 10 120 ?40 ?20 0 20 40 60 80 100 120 ps rr (d b) t emp erature (c) ada4627-1 r l = 4.5v < v sy < 18v 07559-068 figure 12 . psrr vs. temperature 60 70 80 90 100 110 120 ?50 ?25 0 25 50 75 100 125 temperature (c) common-mode rejection ratio (db) ada4627-1 v sy = 15v v cm = 11.5v 07559-012 figure 13 . cmrr vs. temperature 0.001 1 10 20 0.01 0.1 1 100 10 i load (ma) v ol ? v ss (v) ada4627-1 t a = 25c v sy = 15v 07559-058 figure 14 . v out sinking vs. i load current 0.001 1 10 20 0.01 0.1 1 100 10 i load (ma) v dd ? v oh (v) ada4627-1 t a = 25c v sy = 15v 07559-057 figure 15 . v out sourcing vs. i load current
ada4627- 1/ada4637 - 1 rev. d | page 8 of 20 0 1 2 3 4 5 6 7 8 0 4 8 12 16 20 24 28 32 36 supply voltage (v) supply current (ma) ada4627-1 t a = 25c so i c p acka g e 07559-015 figure 16 . supply current vs. supply voltage 0.00001 0.0001 0.001 0.01 0.1 0.001 0.01 0.1 1 thd + n (%) amplitude (v rms) ada4627-1 t a = 25c v sy = 15v v in = 1khz r l = 600 ? 80khz filter 07559-072 figure 17 . thd + n vs. v in ?20 ?10 0 10 20 30 4 0 5 0 60 10 100 1k 10k 100k 1m 10m 100m g ain ( db) freq u enc y (khz) a v = +1 00 a v = +1 0 a v = +1 07559-070 ada4627-1 t a = 25c v sy = 15v figure 18 . close d - loop gain vs. frequency 0.01 0.1 1 10 thd + n (%) frequency (khz) 0.01 0.001 0.0001 0.00001 ada4627-1 t a = 25c v sy = 15v v in = 810mv r l = 600 ? 80khz filter 07559-071 figure 19 . thd + n vs. frequency 0.1 1 10 100 1,000 10,000 10 30 50 70 90 110 130 i b (pa) temperature (c) 07559-078 y = 0.2895 0.0647x r 2 = 0.9991 extrapolated measured ada4627-1 v sy = 15v figure 20 . input bias current vs. temperature i b (pa) v cm (v) +25oc +85c i b + i b + i b ? i b ? ?15 ?10 ?5 0 5 10 15 ada4627-1 v sy = 15v 100 75 50 25 0 ?25 ?50 ?75 ?100 07559-073 figure 21 . input bias current vs. v c m a nd temperature
ada4627- 1/ada4637 - 1 rev. d | page 9 of 20 100 0 200 300 400 500 600 700 800 90 0 1000 1 100 1200 ?15 ?10 ?5 0 5 10 15 i b ( p a ) v cm (v) i b ? i b + ada4627-1 t a = 125c v sy = 15v 07559-074 figur e 22 . input bias current vs. v cm at 125c 80 60 40 20 0 ?20 ?40 ?60 ?80 0 60 120 180 240 300 v os ( v) time (seconds) ada4627-1 t a = 25c v sy = 15v 07559-075 figure 23 . input offset voltage vs. time 60 50 40 30 20 10 0 1 10 100 1000 10,000 overshoot (%) load capacitance (pf) os? ada4627-1 t a = 25c v sy = 15v a v = +1 v in = 100mv p-p os+ 07559-023 figure 24 . small signal overshoot vs. load capacitance 07559-061 output voltage (5v/div) time (1s/div) 1 ada4627-1 t a = 25c a v = ?1 v in = 20v p-p r f = r in = 2k ? c f = 10pf r l = 1k ? c l = 1nf figure 25 . large signal transient response 07559-062 output voltage (5v/div) time (200ns/div) 1 ada4627-1 t a = 25c a v = +1 v in = 20v p-p r f = 0 ? figure 26 . large signal transient response 07559-059 ch1 5.00v output voltage (5v/div) time (200ns/div) 1 ada4627-1 t a = 25c a v = ?1 v in = 20v p-p r f = r in = 2k ? figure 27 . large signal transient response
ada4627- 1/ada4637 - 1 rev. d | page 10 of 20 07559-063 output voltage (5v/div) time (1s/div) 1 ada4627-1 t a = 25c a v = +1 v in = 20v p-p r f = 0 ? r l = 1k ? c l = 1nf figure 28 . large signal transient response 07559-060 output voltage (5v/div) time (200ns/div) 1 ada4627-1 t a = 25c a v = ?1 v in = 20v p-p r f = r in = 2k ? c f = 10pf r l = 1k ? c l = 100pf figure 29 . large signal transient response 07559-064 output voltage (50mv/div) time (200ns/div) 1 ada4627-1 t a = 25c a v = +1 v in = 200mv p-p r f = 0 ? figure 30 . small signal transient response 07559-066 output voltage (50mv/div) time (200ns/div) 1 ada4627-1 t a = 25c a v = ?1 v in = 200mv p-p r f = r in = 2k ? c f = 5pf figure 31 . small signal transient response 07559-065 output voltage ( 50mv/div) time (200ns/div) 1 ada4627-1 t a = 25c a v = +1 v in = 200mv p-p r f = 0 ? r l = 1k ? c l = 1nf figure 32 . sma ll signal transient response 07559-067 output voltage (50mv/div) time (200ns/div) 1 ada4627-1 t a = 25c a v = ?1 v in = 200mv p-p r f = r in = 2k ? c f = 5pf r l = 1k ? c l = 100pf figure 33 . small signal transient response
ada4627- 1/ada4637 - 1 rev. d | page 11 of 20 ?20 ?15 ?10 ?5 0 5 10 15 20 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 time (ms) amplitude (v) ada4627-1 t a = 25c v sy = 15v 07559-033 v in v out figure 34 . no phase reversal 07559-076 input voltage (5v/div) output voltage (1mv/div) time (200ns/div) 2 1 v in v out ada4627-1 t a = 25c v sy = 15 figure 35 . negative settling time to 0.01% 10k 100k 1m 10m 100m gain (db) and phase (degrees) frequency (hz) ada4637-1 v sy = 15v t a = 25oc a v = ?4 r in = 500 r f = 2k c f = 4.8pf c l = 35pf phase gain 140 120 100 80 60 40 20 0 ?20 ?40 ?60 ?80 ?100 07559-082 figure 36 . open - loop gain and phase vs. frequency 07559-077 input voltage (5v/div) output voltage (1mv/div) time (200ns/div) 2 1 v in v out ada4627-1 t a = 25c v sy = 15 figure 37 . positive settling time to 0.01% output voltage (200mv/div) time (1s/div) 1 ada4627-1 t a = 25c v sy = 15v dut gain = 100 4th order band pass fixture gain = 10k total gain = 1m 07559-040 figure 38 . 0.1 hz to 10 hz noise 10k 100k frequenc y (hz) 1m 10 100 1k 10m 100m cmrr (db) 100 80 60 40 20 0 ada4637-1 v sy = 15v t a = 25oc 07559-083 figure 39 . cmrr vs. frequency
ada4627- 1/ada4637 - 1 rev. d | page 12 of 20 0 20 40 60 80 100 120 10 100 1k 10k 100k 1m 10m 100m psrr (db) frequency (hz) psrr+ psrr? ada4637-1 v sy = 15v a v = +5 t a = 25 c 07559-081 figure 40 . psrr vs. frequency ?10 0 10 20 30 40 50 100 1k 10k 100k 1m 10m 100m gain (db) frequenc y (hz) ada4637-1 v sy = 15v r f = 1k, c f = 4.8pf t a = 25oc a v = +5 a v = +10 a v = +100 07559-079 figure 41 . closed - loop gain vs. frequency 07559-084 time (200ns/div) output voltage (5v/div) ada4637-1 t a = 25 c a v = +5 v sy = 15v r in = 500 ? r f = 2k ? c f = 3pf figure 42 . large s ignal t ransient r esponse 07559-085 time (200ns/div) output voltage (100mv/div) ada4637-1 t a = 25 c a v = +5 v sy = 15v r in = 500 ? r f = 2k ? c f = 4.8pf c l = 50pf figure 43 . small s ignal t ransien t r esponse 07559-086 time (100ns/div) output vo lt age (5v/div) ada4637-1 t a = 25 c a v = ?4 v sy = 15v r in = 500 ? r f = 2k ? c f = 4.8pf figure 44 . slew rate f alling 07559-087 time (100ns/div) output vo lt age (5v/div) ada4637-1 t a = 25 c a v = ?4 v sy = 15v r in = 500 ? r f = 2k ? c f = 4.8pf figure 45 . slew rate rising
ada4627- 1/ada4637 - 1 rev. d | page 13 of 20 1 10 100 1 10 100 1k 10k 100k volt age noise densit y (nv/ hz) frequenc y (hz) ada4637-1 v sy = 15v v cm = 0v t a = 25 c 07559-080 figure 46 . voltage noise density vs. frequency
ada4627- 1/ada4637 - 1 rev. d | page 14 of 20 theory of operation the ada4627 - 1 is a high speed, unity gain stable amplifier with excellent dc charact eristics. the ada4637 - 1 is a decompensated version that is stable at a gain of 5 or greater. t he typical offset voltage of 70 v allow s the amplifier s to be easily configured for high gains with out the risk of excessive output voltage errors. the small temperature drift of 2 v/c ensures a minimum offset voltage error ove r the entire temperature range of ?40c to +125c, making the amplifier s ideal for a variety of sensitive measurement applications in harsh operating environments. input voltage range the ada4627 - 1/ada4637 - 1 are not rail - to - rail input amplifier s; t herefor e , care is required to ensure that both inputs do not exceed the input voltage range. under normal negativ e feedback operating conditions, the amplifier corrects its output to ensure that the two inputs are at the same voltage. however, if either input exc eeds the input voltage range, the loop opens , and large currents begin to flow through the esd protection diodes in the amplifier. these diodes are connected between the inputs and each supply rail to protect the input transistors against an electrostatic discharge event, and they are normally reverse - biased. however, if the input voltage exceeds the supply voltage, these esd di odes can become forward - biased. without current limiting, excessive amounts of current can flow through these diodes, causing per manent damage to the device. if inputs are subject to over voltage, insert appropriate series resistors to limit the diode current to less than 5 ma. input offset voltage adjus t range the ada4627 - 1/ada4637 - 1 soic package s ha ve offset adjust pins for compat ib ility with some existing designs. the recommended offse t nulling circuit is shown in figure 47. 07559-051 2 3 6 7 4 ada4627-1 ?v s +v s 100k? 1 5 figure 47 . standard offset null circuit with a 100 k ? potentiometer, the adjustm ent range is more than 11 mv. however, the v os temperature drift increase s by several v/ c for eve ry millivolt of offset adjust. the ada4627 - 1/ada4637 - 1 ha ve matching thin film resistors that are laser trimmed at two temperatures to minimize both offset voltage and offset volt age drift. the offset voltage at room temperature is less than 0.5 mv, and the offset voltage drift is only a few v / c or less; therefore, it is not recommended to use the offset adjust pins, especially for offset adju st of a complete signal chain. signal chain offset can be addressed with an auto - zero amplifier use d to form a composite amplifier; or , if the ada4627 - 1 or the ada4637 - 1 is in an inverting amplifier stage, it can be modified easily to add a potentiometer ( see figure 4 8 ) . the lfcsp package does not have offset ad just pins. 07559-052 2 3 6 ada4627-1 + v out ? v in + ? r f r in 200? 100k? 499k? 499k? 0.1f ?v s +v s figure 48 . alternate offset null circuit for inverting stage input bias current because t he ada4627 - 1/ada4637 - 1 ha ve a jfet input stage , the input bias current, due to the reverse - biased junction, has a leakage current that approximately doubles every 10 c. the power dissipation of the part, combined with the thermal resistance of the package, result s in the junction temperature increasing up 20 degrees to 30 degrees celsi us above ambient. thi s parameter is tested with high speed ate equipment, which does not result in the die te mperature reaching equilibrium. this is correlated with bench measurements to match the guaranteed maximum at room temperature shown in table 2 . the input current can be reduced by keeping the temperature as low as possible and using a light load on the output . noise considerations the jfet input stage offers very low input voltage noise and input current noise. the therma l noise of a 1 k ? resistor at room temperature is 4 nv/ hz; therefore, low values of resis tance should be used for dc - coupled inverting and non inver ting amplifier configurations. in the ca se of transimpedance amplifiers (tias), cu rrent noise is more important. the ada462 7 - 1/ada4637 - 1 are an excellent choice f or both of these applications. analog devices offers a wide variety of low voltage noise and low current noise op amps in a variety of processes that are optimized for di fferent supply voltage ranges. refer to a pplica tion n ote an - 940 for a discussion of noise, calculations, and selection tables for more than three dozen low noise , op amp families.
ada4627- 1/ada4637 - 1 rev. d | page 15 of 20 thd + n measurements tota l harmonic distortion plus n oise (thd + n) is usua lly measured with an audio an alyzer , such as those from audio precision, inc ? . the analyzer consists of a low distortion oscillator that is swept from the starting freq uency to the ending frequency. the oscillator is connected to the circuit under test, an d the output of the cir cuit goes back to the analyzer. the analyzer has a tunable notch filter in lock s tep with the swept oscillator. this re moves the fundamental frequency but allow s all of the harmonics and wide band noise to be measured with an integr ating voltmeter . however, th ere is a switchable low - pass filter in series with the notch filter. if the sine wave is at 100 h z, then the tent h harmonic is still at 1 khz; therefore, having a low pa ss at 80 khz is not a problem. when the oscillator reaches 20 khz, the fourth harmonic (80 khz) is pa r tially attenuated, resulting in a lower reading from the voltmeter. when evaluating thd + n curves from any manufacturer, careful attention should be paid to the test conditions. the d ifference between an 80 khz low - pass filter and a 500 khz filter is shown in figure 49. 0.01 0.1 1 10 100 thd + n (%) frequency (khz) 80khz filter 500khz filter 0.01 0.001 0.0001 0.00001 ada4627-1 t a = 25c v sy = 15v v in = 810mv r l = 600 ? 07559-017 figure 49 . thd + n vs. frequency printed circuit boar d layout , bias current , and b ypassing to take advantage of the very low input bias curren t of the ada4627 - 1/ada4637 - 1 at room temperature, lea kage paths must be considered. a printed circuit board (pcb) , with dus t and humidity, can have 100 m of resistance over a few tenths of an inch. a 1 mv differential between the two points result s in 10 pa of leakage current , more than the guaranteed maximum. the op amp inputs should be guarded by surrounding the nets with a metal trace maint ained at the predicted voltage. in the case of an inverting configuratio n or transimpedance amplifier, (see figure 50 ), the inverting and non inverting nodes can be surrounded by traces held at a quiet analog ground. 07559-053 2 3 6 8 ada4627-1 + v out ? i n c f r f guard figure 50 . inverting amplifier with guard for a non inverting configur ation, the trace can be driven from the feedback divider, but the resistors should be chosen to offer a l ow impedance drive to the trace (see figure 51). 07559-054 3 2 6 8 ada4627-1 + v out ? v s + ? guard r f r i figure 51 . noninverting amplifier with guard the board layout should be compact wit h traces as short as possible. for second - order board considerations, such as triboelectric effects and piezoelectric effects, as well as a table of insulating material properties, see the ad549 data sheet. in some cases, shielding from air currents may be helpful. a general rule of thumb , for op amps with gain bandwidth products higher than 1 mhz, bypass capacitors s hould be very close to the part, within 3 mm. each supply should be bypassed with a 0.01 f ceramic capacitor in parallel with a 1 f bulk decoupling capacitor. the ceramic capacitors should be closer to the op amp. sockets, which add inductance and capacitance, should not be used. output phase reversa l output phase reversal occurs in some ampli fiers when the input common - mode voltage range is exceeded. as common - mode voltage is moved outside the common - mode range, the outputs of these amplifiers can suddenly jump in the opposite direction to the supply rail. this is the result of the differentia l input pair shutting down, causing a radical shifting of internal voltages that results in the erratic output behavior. the ada4627 - 1/ada4637 - 1 amplifier s ha ve been carefully designed to prevent any output phase r eversal if both inputs are main tained wit hin the specified input voltage range. if one or both inputs exceed the input voltage range but remain within the supply rails, an internal lo op opens and the output varies. therefore, the inputs should always be a minimum of 3 v away from either supply ra il .
ada4627- 1/ada4637 - 1 rev. d | page 16 of 20 decompensated op a mps the ada4637 - 1 is a decompensated op amp, and , as such, must always be operated at a noise gain of 5 or greater. see tutorial mt - 0 33, voltage feedback op amp gain and bandwidth, at www.analog .com for more information. driving capacitive l oads adding capacitance to the output of any op amp result s in addi - tional phase shift, which reduces stability and lead s to overshoot or oscillat ion . the ada4627 - 1/ada4637 - 1 ha ve a high phase margin and low output impedance, so they can drive reasonable values of capacitance. this is a common situation when an amplifier is used to drive the input of switched capacitor adcs. for other considerations and various circuit solutions, see the analog dialog ue artic le titled ask the applications engineer - 25, op amps driving capacitive loads , available at www.analog.com .
ada4627- 1/ada4637 - 1 rev. d | page 17 of 20 outline dimension s 090308 -b 1 e x p o s e d p a d ( b o t t o m v i e w ) 0.50 bsc pin 1 indica t or 0.50 0.40 0.30 t o p v i e w 12 max 0.7 0 max 0.6 5 typ 0.9 0 max 0.8 5 nom 0.05 max 0.01 nom 0.2 0 ref 1.89 1.74 1.59 4 1.60 1.45 1.30 3.25 3.00 sq 2.75 2.95 2.75 sq 2.55 5 8 pin 1 indic a t or sea tin g plane 0.30 0.23 0.18 0.6 0 max 0.60 max for proper connec tion of the expose d pad, refer to the pin configuration section of this data she et. figure 52 . 8- lead lead frame chip scale package [ lfcsp_vd ] 3 m m 3 mm body, very thin, dual lead (cp - 8 - 2) dimensions shown in millimeters controlling dimensions are in millimeters; inch dimensions (in p arentheses) are rounded-off millimeter equi v alents for reference on l y and are not appropri a te for use in design. compliant t o jedec s t andards ms-012-a a 012407- a 0.25 (0.0098) 0.17 (0.0067) 1.27 (0.0500) 0.40 (0.0157) 0.50 (0.0196) 0.25 (0.0099) 45 8 0 1.75 (0.0688) 1.35 (0.0532) sea ting plane 0.25 (0.0098) 0.10 (0.0040) 4 1 8 5 5.00 (0.1968) 4.80 (0.1890) 4.00 (0.1574) 3.80 (0.1497) 1.27 (0.0500) bsc 6.20 (0.2441) 5.80 (0.2284) 0.51 (0.0201) 0.31 (0.0122) coplanarit y 0.10 figure 53 . 8 - lead standard small outline package [soic_n] narrow body (r - 8) dimensions shown in millimeters and (inches)
ada4627- 1/ada4637 - 1 rev. d | page 18 of 20 ordering guide model 1 tempe rature range package description package option branding ada4627 - 1acpz -r2 ?40c to +125c 8 - lead lfcsp_vd cp -8 -2 a29 ada4627 - 1acpz -rl ?40c to +125c 8 - lead lfcsp_vd cp -8 -2 a29 ada4627 - 1acpz -r7 ?40c to +125c 8 - lead lfcsp_vd cp -8 -2 a29 ada4627 - 1arz ?4 0c to +125c 8 - lead soic_n r -8 ada4627 - 1arz -rl ?40c to +125c 8 - lead soic_n r -8 ada4627 - 1arz -r7 ?40c to +125c 8 - lead soic_n r -8 ada4627 - 1brz ?40c to +125c 8 - lead soic_n r -8 ada4627 - 1brz -r7 ?40c to +125c 8 - lead soic_n r -8 ada4627 - 1brz -rl ? 40c to +125c 8 - lead soic_n r -8 ada463 7 - 1acpz -r2 ?40c to +125c 8 - lead lfcsp_vd cp -8 -2 a2s ada46 3 7 - 1acpz -rl ?40c to +125c 8 - lead lfcsp_vd cp -8 -2 a2s ada463 7 - 1acpz -r7 ?40c to +125c 8 - lead lfcsp_vd cp -8 -2 a2s ada4637 - 1arz ?40c to +125c 8 - lead so ic_n r -8 ada4637 - 1arz -rl ?40c to +125c 8 - lead soic_n r -8 ada4637 - 1arz -r7 ?40c to +125c 8 - lead soic_n r -8 ada4637 - 1brz ?40c to +125c 8 - lead soic_n r -8 ada4637 - 1brz -r7 ?40c to +125c 8 - lead soic_n r -8 ada4637 - 1brz -rl ?40c to +125c 8 - lead s oic_n r -8 1 z = rohs compliant part.
ada4627- 1/ada4637 - 1 rev. d | page 19 of 20 notes
ada4627- 1/ada4637 - 1 rev. d | page 20 of 20 notes ? 2009 - 2010 analog devices, inc. all rights reserved. trademarks and registered trademarks are the property of their respective owners. d07559 - 0 - 10/10(d)

▲Up To Search▲

Price & Availability of ADA4627-1ARZ

	To Download ADA4627-1ARZ Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .