mp8110 precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 1 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. the future of analog ic technology description the mp8110 is a low-cost, precision, high-side current-sense amplifier. this device operates from a single 2.5v to 40v supply and typically consumes 12a. it is ideal for today?s notebook computers, cell phones and other systems where battery/dc current monitoring is critical. high-side current monitoring is especially useful in battery-powered systems since it does not interfere with the ground path of the battery charger. the input common-mode range of 1.4v to 40v is independent of the supply voltage and ensures that the current-sense feedback remains viable even when connected to a 2-cell battery pack in deep discharge. this device is available in 8-pin soic and msop packages. features ? low-cost, compact current-sense solution ? 12a typical supply current ? 2.5v to 40v operating supply voltage ? 1.4v to 40v input common mode range ? 3a typical shutdown current ? 400v input offset voltage ? high current sensing capability ? integrated buffer amplifier ? available in 8-pin soic and msop packages, applications ? portable pcs ? pda?s ? smart battery packs ? cell phones ? portable test/measurement systems ? battery-operated systems ? energy management systems ?mps? and ?the future of analog ic technology? are registered trademarks of monolithic power systems, inc. typical application mp8110 rg1 vcc shdn gnd rg2 out2 out1 c out opt. c gs 100pf v in + 10uf 0.1uf shutdown on off c 5 i load
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 2 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. package reference shdn nc rg1 gnd out2 vcc rg2 out1 1 2 3 4 8 7 6 5 top view part number* package temperature MP8110DS soic8 ?40 c to +85 c * for tape & reel, add suffix ?z (eg. MP8110DS?z) for rohs compliant packaging, add suffix ?lf (eg. MP8110DS?lf?z) absolute maxi mum ratings (1) vcc, rg1, rg2 to gnd..............?0.3v to +42v max differential input voltage, rg1 to rg2..... 5v max junction temperature (t j ) ................150c storage temperature ............. ?65c to +150c recommended operating conditions (2) v cc , rg1, rg2 to gnd ...................2.5v to 40v operating ambient temperature?40c to +85c shdn nc rg1 gnd out2 vcc rg2 out1 1 2 3 4 8 7 6 5 top view part number* package temperature mp8110dk msop8 ?40 c to +85 c * for tape & reel, add suffix ?z (eg. mp8110dk?z) for rohs compliant packaging, add suffix ?lf (eg. mp8110dk?lf?z) thermal resistance (3) ja jc soic8..................................... 90 ...... 42... c/w msop8 .................................. 150 ..... 65... c/w continuous power dissipation (t a =70c) ............................................... 800mw notes: 1) exceeding these ratings may damage the device. 2) the device is not guaranteed to function outside of its operating conditions. 3) measured on approximately 1? square of 1 oz copper. electrical characteristics v cc = 24v, v shdn = 0v, t a = +25 c, unless otherwise noted. parameter symbol conditions min typ max units supply voltage v cc 2.5 40 v supply current i cc i load = 0a, v cc = 40v 12 30 a common mode input voltage v in_cm v cc > v in low 1.4 v v cc > v in high 40 out1 input offset voltage v os1 0.4 2 mv out2 input offset voltage v os2 1 5 mv input bias current (4) i rg1 , i rg2 4 20 na out1 current accuracy i rg1 /i gs v sense = 100mv 2 5 % no-load out1 error v sense = 0v 0.1 1 a low-level out1 error v sense = 5mv 0.3 2 a no-load out2 error v sense = 0v 0.01 1 a low-level out2 error v sense = 5mv 0.05 2 a power supply rejection ratio psrr 2.5v < v cc < 40v, v sense = 100mv 70 97 db shutdown supply current i cc(shdn) v shdn = 3v 3 6 a
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 3 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. electrical characteristics (continued) v cc = 24v, v shdn = 0v, t a = +25 c, unless otherwise noted. parameter symbol conditions min typ max units shdn threshold voltage v th_shutdown (low - high) 0.7 0.9 1.2 v shdn hysteresis 30 mv t r 17 s out1 rise, fall time (4) t f v sense = 40mv, r gs = 20k ? , r out = 100k ? , r g1 = r g2 = 2k ? , c gs = 100pf, c out = 100pf, 10% to 90% 29 t r 18 s out2 rise, fall time (4) t f v sense = 40mv, r gs = 20k ? , r out = 100k ? , r g1 = r g2 = 2k ? , c gs = 100pf, c out = 100pf, 10% to 90% 26 out1 output voltage range v gs v cc ? 0.15 24 v out2 output voltage range v out v cc ? 1 24 v maximum out1 current (4) i gs 500 a maximum out2 current (4) i out2 5 ma notes: 4) guaranteed by design. 5) input common mode range cannot exceed the supply voltage. pin functions soic8 name description 1 shdn shutdown. connect to ground fo r normal operation. when hi gh, supply current is less than 3a. 2 nc not connected. 3 rg1 gain resistor. connect to battery side of current-sense resistor through the gain resistor. 4 gnd ground or battery negative terminal. 5 out1 output for driving resistor load. 6 rg2 gain resistor. connect to load side of current-sense resistor through the gain resistor. 7 vcc power input. connect to battery input. 8 out2 output for driving capacitive loads.
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 4 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. operation the mp8110 is a current-sense amplifier with a wide operating input voltage range of 2.5v to 40v.it has 1.4v to 40v common-mode range. this feature allows the monitoring of current flow out of a battery in deep discharge, and also enables high-side current sensing up to the supply voltage, v cc . current flows through the sense resistor, r s , which generates a sense voltage v rs . the high precision sense amplifier built into the mp8110 monitors the differential voltage across r s and dynamically adjusts the gate voltage of the internal p-channel mosfet to maintain a equal passing current as i rg1 . the current amplifier gain is therefore set as: r gs / r g1 . choosing sensing resistor given the gain and maximum load current, select r s such that v rs does not exceed +0.25v and v out1 does not exceed 5v. to measure lower currents more accurately, use a high value for rs. a higher value develops a higher sense voltage, which overcomes offset voltage errors of the internal current amplifier. in applications of monitoring very high current, ensure r s is able to dissipate its own i 2 r losses. if the resistor rating power is exceeded, its value may drift or it may fail altogether, causing a differential voltage across the terminals in excess of the absolute maximum range (0.25v).
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 5 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. bias + enable shdn nc rg1 rg2 buffer sense amplifier out2 gnd out1 vcc -- + -- + v out1 i rgs r gs r g1 r g2 r s to load v rs i load i rg1 figure 1?functional block diagram application information component selection table 1?suggested component values (refer to typical circuit on page 1) full-scale load current, i sense (a) current sense resistor (m ? ) gain setting resistor (k ? ) (r g1 = r g2 ) r gs (k ? ) gain 0.1 500 2 20 10 1 50 2 20 10 5 10 2 20 10 10 5 2 20 10 the value of v out1 can be obtained with the equation: gain r i r r r i v s load 1 g gs s load 1 out = = where r g1 is the sense resistor and i load is the load current.
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 6 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. typical performanc e characteristics v in =24v, r g1 =r g2 =2k ? , r g3 =20k ? , r s =20m ? , c gs =100pf, c 5 =0.1f, t a = +25oc, unless otherwise noted. ) a m ( t n e r r u c y l p p u s 0 20 40 60 80 100 120 140 temperature ( c) supply current vs. temperature v 1 t u o ) v m ( t e s f f o _ v out1 offset vs. temperature ) b d ( r r s p frequency (hz) psrr vs. frequency ) v m ( e g a t l o v t u p t u o temperature ( c) temperature ( c) v out1 vs. temperature 2.0a 5.0a 0.1a ) a u ( t n e r r u c y l p p u s ) a u ( t n e r r u c d n h s shut down current vs. ) % ( r o r r e 0 8 16 24 32 40 input voltage (v) input voltage (v) input voltage (v) v out1 error vs. input voltage vs. load current ) v m ( e g a t l o v t u p t u o v 1 t u o ) v m ( 01 2 34 5 01234567 load current(a) load current(a) v out1 vs. load current 0 0 5 10 15 20 25 30 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 200 400 600 800 1000 0 200 400 600 800 1000 1200 2 1018263442 0.001 0.1 10 1000 100000 10000000 2 1018263442 -40 -15 10 35 60 85 -40 -15 10 35 60 85 -45 -15 10 35 60 85 10 8 6 4 2 0 30 24 18 12 6 0 1.0 0.8 0.6 0.4 0.2 0 25 20 15 10 5 0 output error v out1 v out2 input voltage supply current vs. input voltage
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 7 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. typical performanc e characteristics (continued) v in =24v, r g1 =r g2 =2k ? , r g3 =20k ? , r s =20m ? , c gs =100pf, c 5 =0.1f, t a = +25oc, unless otherwise noted. transient response transient response shdn low to high i load =2a shnd high to low i load =2a v shnd 2v/div. v out1 0.2v/div. i load 2a/div. v shnd 2v/div. v out1 0.2v/div. i load 2a/div. v out1 0.5v/div. v out2 0.5v/div. i load 2a/div. v out1 0.5v/div. v out2 0.5v/div. i load 2a/div. 20us/div. 20us/div. 100us/div. 100us/div. v in =24v, i load: 0a to 2a v in =40v, i load: 1a to 3a
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 8 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. typical application -- + -- + mp8110 rg1 vcc shdn gnd rg2 out2 out1 ouput ouput1 ouput2 v in gnd c3 1uf c4 200pf c5 100nf mp8103 mp8103 r12 10k q1 c1 0.1uf + c2 10uf figure 2?current control oscillator
mp8110 ? precision high-side current-sense amplifier mp8110 rev. 0.9 www.monolithicpower.com 9 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. package information soic8 0.016(0.41) 0.050(1.27) 0 o -8 o detail "a" 0.010(0.25) 0.020(0.50) x 45 o see detail "a" 0.0075(0.19) 0.0098(0.25) 0.150(3.80) 0.157(4.00) pin 1 id 0.050(1.27) bsc 0.013(0.33) 0.020(0.51) seating plane 0.004(0.10) 0.010(0.25) 0.189(4.80) 0.197(5.00) 0.053(1.35) 0.069(1.75) top view front view 0.228(5.80) 0.244(6.20) side view 14 85 recommended land pattern 0.213(5.40) 0.063(1.60) 0.050(1.27) 0.024(0.61) note: 1) control dimension is in inches. dimension in bracket is in millimeters. 2) package length does not include mold flash, protrusions or gate burrs. 3) package width does not include interlead flash or protrusions. 4) lead coplanarity (bottom of leads after forming) shall be 0.004" inches max. 5) drawing conforms to jedec ms-012, variation aa. 6) drawing is not to scale. 0.010(0.25) bsc gauge plane
mp8110 ? precision high-side current-sense amplifier notice: the information in this document is subject to change wi thout notice. users should warra nt and guarantee that third party intellectual property rights are not infringed upon w hen integrating mps products into any application. mps will not assume any legal responsibility for any said applications. mp8110 rev. 0.9 www.monolithicpower.com 10 9/21/2007 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2007 mps. all rights reserved. msop8 note: 1) control dimension is in inches. dimension in bracket is in millimeters. 2) package length does not include mold flash, protrusion or gate burr. 3) package width does not include interlead flash or protrusion. 4) lead coplanarity (bottom of leads after forming) shall be 0.004" inches max. 5) pin 1 identification has half or full circle option. 6) drawing meets jedec mo-187, variation aa. 7) drawing is not to scale. seating plane 0.030(0.75) 0.037(0.95) 0.043(1.10)max 0.002(0.05) 0.006(0.15) front view bottom view pin 1 id (note 5) 0.114(2.90) 0.122(3.10) 0.187(4.75) 0.199(5.05) 1 4 5 8 0.010(0.25) 0.014(0.35) 0.0256(0.65)bsc 0.114(2.90) 0.122(3.10) top view 0.004(0.10) 0.008(0.20) side view gauge plane 0.010(0.25) 0.016(0.40) 0.026(0.65) 0 o -6 o recommended land pattern 0.016(0.40) 0.0256(0.65)bsc 0.181(4.60) 0.040(1.00)
|
