aic1084 5a low dropout positive regulator analog integrations corporation si-soft research center ds-1084g-01 073108 3a1, no.1, li-hsin rd. i , science park , hsinchu 300, taiwan , r.o.c. tel: 886-3-5772500 fax: 886-3-5772510 www.analog.com.tw 1 features dropout voltage 1.5v at 5a output current. fast transient response. extremely tight line and load regulation. current limiting and thermal protection. adjustable output voltage or fixed 1.5v, 1.8v, 2.5v, 3.3v. standard 3-pin power packa ges. applications mother board i/o power supplies. microprocessor power supplies. high current regulator. post regulator for switching supply. description the aic1084 is a low dropout three terminal regulator with 5a output current capability. the output voltage is adjustable with the use of a resistor divider or fixed 1.5v, 1.8v, 2.5v and 3.3v. dropout voltage is guaranteed to be at maximum of 1.5v with the maximum output current. its low dropout voltage and fast transient response make it ideal for low voltage microprocessor applications. current limit and thermal protection provide protection against any overload condition that would create excessive junction temperatures. typical application circuit c2 10 f (note1) v out 3.3v v in 5v + + v ref rf2 205 ? 1% a dj aic1084 c1 10 f 2 3 1 rf1 125 ? 1% v ref =v out -v adj =1.25v (typ.) v out =v ref x (1+rf2/rf1)+ i adj x rf2 i adj =55 a (typ.) (1) c1 needed if device is far away from filter capacitors. (2) c2 required for stability. adjustable voltage regulator c2 10 f (note1) v out 3.3v v in 5v + + gnd c1 10 f aic1084-33 2 1 3 fixed voltage regulator
aic1084 2 ordering information a ic1084-xx xxxx example: aic1084-18cetr 1.8v version in to-252 package & taping & reel packing type example: aic1084-18pmtr 1.8v version in to-263 lead free package & taping & reel packing type pin configuration 2 3 1 to-252 top view 1: adj (gnd) 2: vout (tab) 3: vin 23 1 1 2 3 to-263 top view 1: adj (gnd) 2: vout (tab) 3: vin to-220 front view 1: adj (gnd) 2: vout (tab) 3: vin packing type tb: tube tr: taping & reel packaging type e: to-252 m: to-263 t: to-220 c: commercial p: lead free commercial g: green package output voltage default: adjustable 15: 1.5v 18: 1.8v 25: 2.5v 33: 3.3v (1.5v version is available under request) absolute maximum ratings vin pin to adj/gnd pin 7v ambient temperature range ?40 c to 85 c maximum junction temperature 125 c storage temperature range ?65 c ~ 150 c lead temperature (soldering) 10 sec. 260 c thermal resistance junction to case to-252 12.5 c/w to-263, to-220 3 c/w thermal resistance junction to ambient to-252 100 c/w (assume no ambient airflow, no heatsink) to-263 60 c/w to-220 50 c/w absolute maximum ratings are those values beyond which the life of a device may be impaired.
aic1084 3 test circuit refer to typical application circuit. electrical characteristics (v in =5v, t j =25 c, i o =10ma, unless otherwis e specified) (note2) parameter test conditions min. typ. max. unit reference voltage aic1084 (adj) 1.225 1.25 1.275 v output voltage AIC1084-15, v in =5v aic1084-18, v in =5v aic1084-25, v in =5v aic1084-33, v in =5v 1.47 1.76 2.45 3.23 1.50 1.80 2.50 3.30 1.53 1.84 2.55 3.37 v adj : 2.75v v in 7v v out =1.25v line regulation fix : v out +1.5v v in 7v 0.015 0.2 % load regulation 10ma < i o < 5a 0.6 % dropout voltage ?v out , ?v ref =1% 10ma i o 5a 1.4 1.5 v current limit 5 6 a gnd current (fix) v out +1.5v v in 7v 11.5 14 ma adjusted pin current 2.75v v in 7v 55 120 a adjusted pin current change ( ?i adj ) 2.75v v in 7v 0.2 5 a temperature stability i o =0.5a 0.5 % minimum load current 5 10 ma rms output noise (% of v out ) 10hz f 10khz 0.003 % ripple rejection ratio 120hz input ripple c out =25 f (v in -v out )=3v 60 72 db thermal shutdown temperature note 3 165 c note 1: to avoid output oscillation, aluminum electrolytic output capacitor is recommended and ceramic capacitor is not suggested. note 2: specifications are production tested at t a =25 c. specifications over the -40 c to 85 c operating temperature range are assured by design, characte rization and correlation with statistical quality controls (sqc). note 3: guarantee by design.
aic1084 4 typical performance characteristics fig. 1 load transient response fig. 2 line transient response time ( s) output voltage (mv, ac) input voltage (v) 0 4 08 01 2 01 6 02 0 0 6.0 7.0 -100 -50 0 50 c in =1 f (tantalum) c out =10 f (tantalum) v out =3.3v 1 2 3 4 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 a ic1084-25 (t j =25
) dropout voltage (v) output current (a) fig. 3 dropout voltage (v out =2.5) 0 2 4 6 8 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 a ic1084 - adj minimun operating current (ma) v in -v out (v) fig. 4 minimum operating current 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 fig. 5 minimum operating current minimum operating current (ma) differential voltage (v) 0 1 2 3 4 5 6 7 8 9 shot circuit current ( a ) v in -v out (v) fig. 6 aic1084 (1.8) short circuit current 10 1 2 3 4 5 6 7 8 a ic1084-18
aic1084 5 typical performance characteristics (continued) 10 1 10 2 10 3 10 4 10 5 10 6 10 7 -80 -70 -60 -50 -40 -30 -20 fig. 7 aic1084 (adj.) ripple rejection c out =3.3 f ri pp le re j ection ratio ( db ) frequency (hz) c out =10 f c out =25 f block diagram vin 55 a a dj v ref 1.25v - + gm + thermal limit current amp. vout gnd for fixed voltage device current limit pin descriptions adj pin - providing v ref =1.25v (typ.) for adjustable v out . v ref =v out -v adj and i adj =55 a (typ.) (gnd pin- power ground.) vout pin - adjustable output voltage. vin pin - power input.
aic1084 6 application information input-output capacitors linear regulators require input and output capacitors to maintain stability. input capacitor at 10 f with a 10 f aluminum electrolytic output capacitor is recommended. power dissipation the aic1084 obtains thermal-limiting circuitry, which is designed to protect the device against overload condition. for continuous load condition, maximum rating of junction temperature must not be exceeded. it is important to pay more attention in thermal resistance. it includes junction to case, junction to ambient. the maximum power dissipation of aic1084 depends on the thermal resistance of its case and circuit board, the temperature difference between the die junction and ambient air, and the rate of airflow. the rate of temperature rise is gr eatly affected by the mounting pad configuration on the pcb, the board material, and the ambient temperature. when the ic mounting with good thermal conductivity is used, the junction temperature will be low even when large power dissipation applies. the power dissipation across the device is p = i out (v in -v out ). the maximum power dissipation is: ja a max-j max r )t-(t p = where t j-max is the maximum allowable junction temperature (125 c), and t a is the ambient temperature suitable in application. as a general rule, the lower temperature is, the better reliability of the device is. so the pcb mounting pad should provide maximum thermal conductivity to maintain low device temperature. application examples 125 r1 205 r2 + 10 f c2 + c1 10 f mmbt2222a r3 1k 1k r4 vin 5v vout aic1084 3 1 a dj 2 3.3v ttl 125 r1 205 r2 + 100 f c2 + 10 f c1 vin vout a ic1084 3 1 a dj 2 cadj 5v 3.3v * cadj can improve ripple rejection fig. 8 v out =3.3v with shutdown fig. 9 improving ripple rejection 125 r1 + 10 f c2 + 10 f c1 vin vout a ic1084 3 1 a dj 2 5v 1.25v + 100 f c2 + 10 f c1 vout a ic1084-33 3 1 2 -3.3v d1 t1 vin floating input fig. 10 v out =1.25v application circuit fig. 11 low dropout negative supply
aic1084 7 physical dimensions to-220 (unit: mm) section a-a b a2 l l1 b2 e aa e p q d h1 a with plating base metal a1 c d1 -- 5.85 1.15 2.04 0.51 2.54 bsc 9.66 14.23 0.35 0.38 h1 a2 d e a1 e c b2 b 6.85 2.92 1.77 1.39 10.66 16.51 0.61 1.01 3.56 min. s y m b o l a4 max. to-220 millimeters d1 8.38 9.02 . 8 2 2.54 3.54 12.70 q p l1 l 3.42 6.35 4.08 14.73 note: 1.refer to jedec to-220ab. 2.controlling dimension is millim eter, converted inch dimensions are not necessarily exact.
aic1084 8 to-252 (unit: mm) c2 see view b a h b3 a a e e d l3 l4 c base metal with plating seating plane b section a-a view b a1 l l1 gauge plane l2 millimeters to-252-3l max. 2.38 a s y m b o l min. 2.19 0.13 5.46 0.61 0.89 6.22 6.73 0.89 2.67 ref 0.51 bsc 10.41 1.78 2.03 2.28 bsc a1 b b3 c2 e d c h l l1 l2 l3 e 1.02 l4 0.00 4.95 0.46 0.46 5.33 6.35 9.40 1.40 0.89 0.64 -- 0 8 note: 1.refer to jedec to-252aa and ab. 2.dimension d and e do not include mold flash, protrusions o r gate burrs. mold flash, protrusion or gate burrs shall not exceed 6 mil per side. 3.controlling dimension is millim eter, converted inch dimensions are not necessarily exact.
aic1084 9 to-263 (unit: mm) 0 0.51 -- 1.78 14.61 9.65 8.38 1.14 0.38 1.14 0.00 e l3 l2 l1 l h c d e c2 b2 b a1 2.54 bsc 8 1.68 1.78 2.79 15.88 0.25 bsc 0.99 10.67 9.65 1.65 0.74 1.78 0.25 4.06 min. s y m b o l a4 . 8 3 max. to-263-3l millimeters -- b2 e l view b l3 gauge plane a1 seating plane with plating base metal section a-a b see view b c l2 e a a h d l1 a c2 note: 1.refer to jedec to-263ab. 2.controlling dimension is millim eter, converted inch dimensions are not necessarily exact. note: information provided by aic is believed to be accurate and reliable. however, we cannot assume responsibility for use of any ci rcuitry other than circuitry entirely embodied in an aic product; nor for any infringement of patents or other rights of third parties that may result from its use. we reserve the right to c hange the circuitry and specif ications without notice. life support policy: aic does not authorize any aic product for us e in life support devices and/or systems. life support device s or systems are devices or systems which, (i) are intended for surgic al implant into the body or (ii) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeli ng, can be reasonably expected to result in a significant injury to the user.
|
