microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 1 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products description the lx8820 is a single channel positive-voltage linear regulator. the regulator has a 3.3v fixed output featuring ultra low-dropout and high accuracy. the lx8820 regulator is stable with ceramic or tantalum low-value capacitors, typically 2.2 f on the outputs, allowing designers flexibility in external component selection. the lx8820 features on-chip trimming of the internal voltage reference enabling precise output voltage, typically 0.3% over a wide temperature range. the cmos wafer process offers elect rical performance improvements compared to bipolar technology for the regulator, increasing regulator efficiency by minimizing operating ground current (typically < 200ua). the low rdson of the pmos outpu t stage results in ultra low dropout (typically 0.45v @ 1a). output voltage overshoot is controlled using slew rate control, as v in is applied, typically v out overshoot < 2% for v in 1v/us ramp. transient response to a step load is fast and controlled, v out overshoot remains within 2% of nominal for 400ma step sizes. thermal shutdown, current limit and short circuit current protection are integrated on-chip for survival during fault conditions. microsemi?s 3x3mm body size (mo- 229) micro- p ower package enables maximum power dissipation and ease o f assembly using surface mount technology. important: for the most current data, consult microsemi ?s website: http://www.microsemi.com key features ? accurate output voltage ? typical dropout of 0.7v at 1a and 0.25v at 0.8a ? independent thermal and current limit protection ? low tolerance load regulation (0.4%) ? wide dc supply voltage of 4.1v to 7v ? loop stability independent of output capacitor type ? available in 6 pin jedec mo- 229 surface mount package applicati ons/benefits ? 5v to 3.3v regulators ? hard disk drives, cd-roms ? adsl and cable modems ? battery charging circuits ? instrumentation ? pc peripherals application circuits 1: v 2: gnd 3: n/c in 6: v 5: v 4: v in out out 4.7uf 4.7uf lx8820 v 3.8 to 6v in v 3.3v @ 1a out package order info t j ( c) o utput v lm plastic mlp 6-pin mlp part marking 0 to 125 3.3v LX8820-33CLM 882j or 8820 note: available in tape & reel. append the letter ?t? to the part number. (i.e. LX8820-33CLMt) l l x x 8 8 8 8 2 2 0 0
microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 2 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products absolute maximum ratings input voltage (v in )........................................................................................................10v load current (intern ally limited) ...................................................................................2a power dissipati on....................................................................................internal ly limited short-circuit protec tion........................................................................................ inde finite operating junction temperature ............................................................................... 150 c package peak temperature for solder re flow (max exposure of 40 seconds).......... 250 c note: exceeding these ratings could cause damage to th e device. all voltages are with respect to ground. currents are positive into, ne gative out of specified terminal. thermal data lm plastic mlp 6-pin t hermal r esistance -j unction to t ab , jt 8c/w t hermal r esistance -j unction to a mbient , ja (t ypical , depending on mounting / pcb layout ) 29-35c/w junction temperature calculation: t j = t a + (p d x ja ). the ja numbers are guidelines for the therma l performance of the device/pc-board system. all of the above assume no ambient airflow. ja can vary significantly depending on mounting technique. (see application notes section: thermal considerations) package pin out 1 v 2 gnd 3 n/c in v v v in ou out 6 5 4 t lm p ackage (top view) * must be connected to gnd or left floating (see pg 7 for details) n/c = not internally connected functional pin description p in n ame d escription v in positive unregulated supply input fo r the regulator. bypass to gnd with at least 2.2f of low esr and esl capacitance. gnd common terminal for ground reference. the input and output bypass capacitors should be connected to this pin. v out regulator output. it is recommended to bypass to gnd with at least 2. 2uf. size your out put capacitor to meet the transient loading requirement. if you have a very dynamic load, a lower esr capacitor will improve the response to these load steps. p p a a c c k k a a g g e e d d a a t t a a
microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 3 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products recommended max operating conditions lx8820-33 parameter symbol min typ max units input voltage v in 4.5 10 v load current (with adequate heat sinking) i l 1200 ma operating junction temperature t j 125 c electrical characteristics unless otherwise specified, the following specificati ons apply over the operat ing ambient temperature 0 c t a 125 c except where otherwise noted and the following test conditions: v in = 5v, i out = 10ma, c 1 = 4.7 f (ceramic), c 2 = 4.7 f (ceramic), & t j = t a using low duty cycling methods. lx8820-33 parameter symbol test conditions min typ max units ` fixed output (3.3v) output voltage v out 5ma < i out < 1a, 4.75v < v in < 5.25v 3.234 3.300 3.366 v line regulation ? v out (v in ) 4.5v < v in < 5.5v, 5ma < i out < 1a 4 9 mv load regulation ? v out (i out ) 10ma < i out < 1a, v in = 4.75v 3 15 mv v do i load = 1a, ? v out = -1% 0.45 v i load = 0.8a, v in = 3.8v 3.0 3.3 3.383 dropout voltage v out i load = 1a, v in = 4.0v 3.0 3.3 3.383 v transient response; v out overshoot at start-up v out v in step 0v to 5v; t r 1us; 10ma < i out < 1a note 2 3.63 v transient response; v out droop to step load v out v in = 5v; t r 1us; 10ma < i out < 1a note 2 3.0 v current limit i out (max) v in < 5.5v 1.0 1.5 a minimum load current i l note 1 0 0.1 ma i out =5ma 205 300 quiescent current i q i out =1000ma, v in < 7v 550 650 ua ripple rejection psrr f=120hz, v in = 5v 50 75 db rms output noise (% of v out ) v out (rms) 10hz < f < 10khz 0.003 %/v thermal shutdown t jsd 140 160 c note 1: minimum load current is defined as the amount of output current required to maintain regulation. note 2: guaranteed by design. e e l l e e c c t t r r i i c c a a l l s s e e l l e e c c t t r r i i c c a a l l s s
microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 4 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products block diagram bias 1.25v v ref v in c 1 10 f note: application circuit above using ceramic capacitors. + - v out c 2 10 f gnd 2 figure 1 ? fixed output b b l l o o c c k k d d i i a a g g r r a a m m
microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 5 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products characteristic curvers lx8820 temp stability, iout=5ma 3.280 3.282 3.284 3.286 3.288 3.290 3.292 3.294 3.296 3.298 3.300 3.302 3.304 -50 -25 0 25 50 75 100 125 150 temp, c vo volt vin=4.5v vin=5.25v vin=7v step load stability t ch3 ch3 50.0mv 50.0mv b b w w ch4 9.25mv m 10.0 s t 16.00% a ch4 12.2mv 3 3 4 ch3: (red) vout, ch4: istep 200ma/div, cin = cout = 4.7f ceramic, load current, dc =100ma supply voltage, fast turn on (trise = 10us) t ch1 ch1 1.00v 1.00v b b w w ch2 1.00v m 1.00ms t 29.80% a ch2 2.18v 1 2 ch1: vin (light blue) ch2: vout, cin = cout = 10f ceramic, load current, dc = 1a short circuit and recovery ch1: vout, ch4: istep, cin = cout = 10f ceramic ch3: (red) vout, ch4: iout 1a/div, cin = cout = 10f ceramic c c h h a a r r t t s s
microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 6 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products application information description the lx8820 is part of a family of ldo (low drop-out) linear regulators in the jedec mo-229 package that offer maximum power dissipation in a low profile surface mount technology. the lx8820 output is fixed at 3.3v output and can supply up to one amp with a regulator design optimized for system efficiency by consuming minimal ground current and directing quiescent current to the load. input capacitor to improve load transient response and noise rejection an input bypass capacitor of at least 2.2uf is required. generally we recommend a 4.7uf ceramic or tantalum or 22uf electrolytic capacitor. output capacitor the regulator requires an output capacitor connected between v out to gnd to stabilize the internal control loop. many types of capacitors are available, with different capacitance values tolerances, temperature coefficients and equivalent series resistance. we recommend a minimum of 4.7uf. to ensure good transient response from the power supply system under rapidly changing current load conditions, designer s generally use additional output capacitors connected in parallel. such an arrangement serves to minimize the effects of the parasitic resistance (esr) and inductance (esl) that are present in all capacitors. the regulator has been tested stable with capacitor esr?s in the range of 0.01 to 2 ohms. we have found it best to us e the same type of capacitor for both input and output bypass. minimum load requirement the lx8820 has a minimum load requirement for proper output regulation specified at 0.1ma. temperature protection the thermal protection shuts the lx8820 down when the junction temperature exceeds 160 0 c. exposure to absolute maximum rated conditions for extended periods may affect device reliability (see thermal considerations below). current limit protection the lx8820 includes over current protection. when the output load current exceeds typically 1.5a, the circuit forces the regulator output to decrease. thermal considerations thermal shutdown protects the integrated circuit from thermal overload caused from a rise in junction temperature during p ower dissipation. this means of protection is intended for fault p rotection only and not as a mean s of current or power limiting during normal application usage. proper thermal evaluation should be done to ensure that the junction temperature dose not exceed it?s maximum rating. operating at the maximum t j of 150c can impact reliability . due to variation in individual device electrical characteristics and thermal resistance , the built in thermal overload protection may be activated at power levels slightly above or below the rate d dissipation. also peak output power should be considered fo r each individual output. power dissipation for regulator can be calculated using the following equation: p d = (v in(max) -v out ) * i out (note: power dissipation resulting from qu iescent (ground) current is negligible) junction temperature of the integr ated circuit can be calculated using: t junction = t junction-tab rise _ + t tab-amb rise + t amb t tab = p d max * jt ; t tab-amb = p d reg * pcb an example: given conditions: t a = 70c, v in = 5.0v, v out = 3.3v, i out = 200ma. calculated values: t j-tab reg = (5v-3.3v) * (200ma) * 8c/w = (340mw) * 8c/w = 2.7c t tab-amb rise = ( 340mw ) * 32c/w = 10.9c t junction = 2.7c + 10.9c + 7 0c = 83.6c it is important to note that although each output of the regulator will produce up to 1.5a in current, the total power dissipation may limit the useful total current draw. the junction temperature should be calculated to insure the maximum junction temperature is not exceeded. a a p p p p l l i i c c a a t t i i o o n n s s
microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 7 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products mechanical drawings lm 6-pin plastic mlp-micro exposed pad e d e b e2 d2 a3 a1 internally connected together, but isolated from all other terminals l2 l l2 a k note: 1. dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006?) on any side. lead dimension shall not include solder coverage. m illimeters i nches dim min max min max a 0.80 1.00 0.032 0.040 a1 0.00 0.05 0 0.002 a3 0.20 ref 0.008 ref b 0.30 0.45 0.012 0.018 d 2.90 3.10 0.114 0.122 e 2.90 3.10 0.114 0.122 e 0.95 bsc 0.037 bsc d2 1.90 2.25 0.075 0.086 e2 1.15 1.65 0.045 0.065 k 0.20 - 0.008 - l 0.30 0.45 0.012 0.018 l2 - 0.10 - 0.004 m m e e c c h h a a n n i i c c a a l l s s
microsemi linfinity microelectronics division 11861 western avenue, garden grove, ca. 92841, 714-898-8121, fax: 714-893-2570 page 8 copyright ? 2000 rev. 1.0a, 2003-06-15 www. microsemi . com lx8820 3.3v/1.2 a ultra low dro p out re g ulator p roduc tion data sheet integrated products notes production data ? information contained in this document is proprietary to microsemi and is current as of publication date. this document may not be modified in any way without the express written consent of microsemi. product processing does not necessarily include testing of all parameters. microsemi reserves the right to change the configuration and performance of the product and to discontinue product at any time. n n o o t t e e s s
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