general description the max8516/max8517/max8518 low-dropout linear regulators operate from input voltages as low as 1.425v and are able to deliver up to 1a of continuous output cur - rent with a maximum dropout voltage of only 200mv. the output voltage can be set from 0.5v to (v in - 0.2v) and is 1.4% accurate over load and line variations, from 0c to +85c. these regulators use small, 1f ceramic input capacitors and 4.7f ceramic output capacitors to deliver 1a out - put current. high bandwidth provides excellent transient response and limits the output voltage deviation to 45mv for a 20ma to 1a load step, with only a 4.7f ceramic out - put capacitor, and the voltage deviations can be reduced further by increasing the output capacitor. designed with an internal p-channel mosfet pass transistor, the max8516/max8517/max8518 feature low 340a (typ) supply current during dropout conditions. soft-start reduces inrush current. other features include a logic-controlled shutdown mode, short-circuit protection, and thermal-overload protection. the max8517 features a power-ok (pok) output that transitions high when the regulator output is within 10% of its nominal output voltage. the max8518 features a 150ms power-on reset output. the parts are packaged in a 10-pin max ? package that includes an exposed pad for optimal power dispation. applications features 1.425v to 3.6v input voltage range guaranteed 200mv dropout at 1a output current 1.4% output accuracy over load, line, and temperature (0c to +85c), 0.6% initial accuracy compatible with ceramic capacitors fast transient response 320a operating supply current <25a shutdown supply current short-circuit protection thermal-overload protection soft-start limits inrush current 19-3188; rev 3; 4/16 max is a registered trademark of maxim integrated products, inc. servers storage networking base stations optical modules post regulators notebooks pdas ate 1 0 m a x 3 m m x 5 m m part temp range pin-package max8516 eub -40c to +85c 10 max max8517 eub -40c to +85c 10 max max8517eub/v+ -40c to +85c 10 max max8518 eub -40c to +85c 10 max /v denotes an automotive qualified part. +denotes lead(pb)-free/rohs-compliant package. max8516max8517 max8518 1f 4.7f input 1.425v to 3.6v output 0.5v to (v in - 0.2v), 1a power-on reset power-ok on off in_por (max8518) pok (max8517) en gnd fb out_ 1 23 4 5 10 98 7 6 n.c.out out fb n.c. in in en max8516 max top view gnd n.c. 1 23 4 5 10 98 7 6 n.c.out out fb pok in in en max8517 max gnd n.c. 1 23 4 5 10 98 7 6 n.c.out out fb n.c. in in en max8518 max gnd por max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators ordering information typical operating circuit pin conigurations evaluation kit available downloaded from: http:///
in, en, pok (max8517), por (max8518), fb to gnd ........................................................ -0.3v to +4.0v out to gnd ................................................. -0.3v to (in + 0.3v) output short-circuit duration .................................... continuous continuous power dissipation (t a = +70c, ep soldered to pc board ground) 10-pin max (derate 10.3mw/c above +70c) ........ 824mw operating temperature range ........................... -40c to +85c junction temperature ...................................................... +150c storage temperature range ............................ -65c to +150c lead temperature (soldering, 10s) ................................. +300c soldering temperature (soldering, 10s) .......................... +240c (circuit of figure 1. v in = +1.8v, v out = +1.5v, en = in, i out = 1ma, t a = -40c to +85c, unless otherwise noted.) (note 1) parameter conditions min typ max units in input voltage range 1.425 3.600 v input undervoltage lockout v in rising, 70mv hysteresis 1.32 1.35 1.38 v out output voltage range 0.5 3.4 v load regulation i out = 1ma to 1a 0.1 %/a line regulation v in = 1.425v to 3.6v, v out = 1.225v, i out = 1ma -0.15 0 +0.15 %/v dropout voltage (v in - v out ) v in = 1.425v, i out = 1a, v fb = 480mv 100 200 mv current limit v in = 3.6v, v out = 3v, v fb = 480mv 1.6 2 2.4 a output shutdown leakage v in = 3.6v, v out = 0, v en = 0 0.25 25 a fb fb threshold accuracy i out = 10ma, t a = +85c 497 500 503 mv v out = 1.225v to 3v, v in = v out + 0.2v to 3.6v, i out = 1ma to 1a 493 507 fb input bias current v fb = 0.5v, v in = 3.6v 0.001 1 a gndgnd supply current v in = 3.6v, v out = 3v, i out = 100ma 320 a dropout, v in = 3.6v, v fb = 480mv 340 600 gnd shutdown current v in = 3.6v, en = gnd 0.25 25 a pok (max8517 only) pok threshold v fb moving out of regulation, v hys = 10mv, in = 1.425v to 3.6v fb high 540 550 560 mv fb low 440 450 460 pok output voltage low v fb = 0.4v or 0.6v, i pok = 1ma 25 200 mv pok output current high v pok = 3.6v 0.001 1 a pok fault delay time from fb to pok 25 50 100 s max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators www.maximintegrated.com maxim integrated 2 absolute maximum ratings stresses beyond those listed under absolute maximum ratings may cause permanent damage to the devi ce. these are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. electrical characteristics downloaded from: http:///
(circuit of figure 1. v in = +1.8v, v out = +1.5v, en = in, i out = 1ma, t a = -40c to +85c, unless otherwise noted.) (note 1) note 1: specifications to t a = -40c are guaranteed by design, not production tested. note 2: measurements at high current are pulse tested, such that the junction temperature is ambient temperature. minimum supply voltage for output accuracy must be at least 1.425v. (circuit of figure 1, v in = +1.8v, v out = +1.5v, i out = 1a, c out = 4.7f, c in = 1f, t a = +25c.) parameter conditions min typ max units por (max8518 only) por reset threshold v fb falling, v hys = 10mv, v in = 1.425v to 3.6v 440 450 460 mv por output voltage low v fb = 0.4v or 0.6v, i por = 1ma 25 200 mv por output current high v por = 3.6v 0.001 1 a por rising delay time from fb to por 105 150 210 ms en enable input threshold v in = 1.425v to 3.6v en rising 1.2 v en falling 0.4 enable input bias current v en = 0 or 3.6v -1 +1 a thermal shutdown thermal-shutdown threshold output on or off t j rising +165 c t j falling +150 output transient load transient i out = 20ma to 1a to 20ma, t rise = t fall = 1s 3 % line transient v in = 0.5v, t rise = t fall = 5s 3 % output voltage vs. load current max8516/17/18 toc02 load current (ma) output voltage (v) 800 600 400 200 1.492 1.494 1.496 1.498 1.500 1.5021.490 0 1000 1200 t a = +85c t a = +25c t a = -40c ground current vs. input voltage max8516/17/18 toc03 input voltage (v) ground current (a) 3.0 2.4 0.6 1.2 1.8 100 200 300 400 500 0 0 3.6 i load = 1a i load = 0.5a i load = 0a output voltage vs. input voltage max8516/17/18 toc01 input voltage (v) output voltage (v) 3.0 2.4 1.8 1.2 0.6 1.35 1.40 1.45 1.50 1.55 1.601.30 0 3.6 t a = -40c to +85c max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators www.maximintegrated.com maxim integrated 3 electrical characteristics (continued) typical operating characteristics downloaded from: http:///
(circuit of figure 1, v in = +1.8v, v out = +1.5v, i out = 1a, c out = 4.7f, c in = 1f, t a = +25c.) dropout voltage vs. load current max8516/17/18 toc05 load current (ma) dropout voltage (mv) 800 600 400 200 25 50 75 100 125 0 0 1000 line input transient (v in = +1.8v to +2.5v, i load = 1a) max8516/17/18 toc06 100s/div v out ac-coupled20mv/div v in ac-coupled0.5v/div load-transient response (i load = 0.1a to 1a) max8516/17/18 toc07 40s/div v out ac-coupled50mv/div i load 1a/div c in = 220f electrolytic cap close to in shutdown response max8516/17/18 toc08 100s/div v out 1v/diven 2v/div i in 1a/div ground current vs. load current max8516/17/18 toc04 load current (ma) ground current (a) 1000 800 600 400 200 275 300 325 350 375250 0 1200 t a = +25c t a = -40c t a = +85c psrr vs. frequency (max8516) max8516/17/18 toc09 frequency (khz) psrr (db) 100 10 1 0.1 10 20 30 40 50 60 70 80 0 0.01 1000 i load = 100ma max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators maxim integrated 4 www.maximintegrated.com typical operating characteristics (continued) downloaded from: http:///
(circuit of figure 1, v in = +1.8v, v out = +1.5v, i out = 1a, c out = 4.7f, c in = 1f, t a = +25c.) fb voltage vs. temperature max8516/17/18 toc10 temperature (c) fb voltage (mv) 60 35 10 -15 499 500 501 502498 -40 85 i load = 10ma output ripple voltage max8516/17/18 toc11 100s/div v out ac-coupled1mv/div overcurrent threshold vs. temperature max8516/17/18 toc12 temperature (c) overcurrent threshold (a) 60 35 10 -15 1.80 1.85 1.90 1.951.75 -40 85 short-circuit current max8516/17/18 toc13 100s/div v out 1v/divi out 2a/div case temperature vs. load current max8516/17/18 toc14 load current (ma) case temperature (c) 800 600 400 200 15 30 45 60 75 0 0 1000 v in = 2.5v; t a = +25c max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators maxim integrated 5 www.maximintegrated.com typical operating characteristics (continued) downloaded from: http:///
pin name description max8516 max8517 max8518 1 1 1 en enable input. set low to place the device in low-current shutdown mode. set high for normal operation. 2, 3 2, 3 2, 3 in regulator input. v in can range from +1.425v to +3.6v. bypass with a 1f or higher ceramic capacitor to gnd. 4, 5, 10 5, 10 4, 10 n.c. no connection. pin 10 is internally pulled down to gnd with a 10k? resistor. leave loating. 6 6 6 gnd ground 7 7 7 fb feedback pin. connect to output through a voltage-divider to set the output. 8, 9 8, 9 8, 9 out regulator output. bypass with a 4.7f ceramic capacitor to gnd (a smaller capacitor can be used if maximum load is less than 1a, i.e., c out = i out (max) x (1f/200ma). 4 pok power-ok output (max8517 only). open-drain output. connect to a positive supply with a pullup resistor. if not used, leave pin unconnected. see the detailed description . 5 por power-on reset output. open-drain output. connect to a positive supply with a pullup resistor. if not used, leave pin unconnected (see the detailed description for more details). ep gnd exposed pad on the underside of the package. solder to the ground plane for proper heat dissipation. max8516max8517 max8518 pok(max8517 only) por (max8518 only) gnd ref overthermal protection overthermal protection en in undervoltage lockout threshold 0.55v0.45v 0.50v error amp with soft-start mos driver with i limit outfb max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators www.maximintegrated.com maxim integrated 6 pin descriptionfunctional diagram downloaded from: http:///
detailed description the max8516/max8517/max8518 are low-input, low- dropout, pmos regulators capable of delivering up to 1a of output current with as little as 200mv of headroom from input to output. the pmos output stage can be driven from input voltages down to +1.425v without sacrificing stability or transient performance. since these regulators have a pmos output device, supply current is not a sig - nificant function of load or input headroom. internal p-channel pass transistor the max8516/max8517/max8518 feature a 100m (typ) p-channel mosfet pass transistor. unlike similar designs using pnp pass transistors, p-channel mosfets require no base drive, which reduces quiescent current. pnp-based regulators also waste considerable current in dropout when the pass transistor saturates and use high base-drive currents under large loads. the max8516/ max8517/max8518 do not suffer from these problems and consume only 340a (typ) of quiescent current under heavy loads, as well as in dropout. short-circuit/thermal fault protection the max8516/max8517/max8518 are fully protected from a short circuit at the output through current-limiting and thermal-overload circuitry. in the fault condition when the output is shorted to ground, the output current is lim - ited to 2a. under these conditions, the part quickly heats up. when the junction temperature reaches +165c, the thermal-overload circuitry turns off the output, allowing the part to cool down. when the junction temperature cools to +150c, the output turns back on and tries to reestablish regulation. current limiting and thermal protection contin - ue until the fault is removed. for continuous operation, do not exceed the absolute maximum junction-temperature rating of t j = +150c. output voltage selection the max8516/max8517/max8518 feature an adjust - able output voltage from 0.5v to 3.4v, using two external resistors connected as a voltage-divider to fb as shown in figure 1. the output voltage is set by the following equation: out fb r1 v v 1 r2 ?? = + ???? where typically v fb = 0.5v. choose r2 5k to optimize quiescent current, accuracy, and high-frequency power- supply rejection. to simplify resistor selection: out fb v r 1 r 2 1 v ? ?? = ?? ?? soft-startinherent soft-start limits inrush current. peak inrush cur - rent is dependent on the value of c out and can be cal - culated as follows: out inrush load c (f) i i 66 ?? = + ?? ?? shutdown mode the max8516/max8517/max8518 include an enable input. to shut down the device, pull en to gnd. for nor - mal operation, connect the en to in. during shutdown, an internal 10k resistor pulls down the output. power-ok (max8517 only) the max8517 features a power-ok (pok) output to indi - cate the status of the output. pok remains high when the regulator output is within 10% of its nominal output volt - age. if the output voltage falls or rises outside this range, pok transitions low. this open-drain output requires an external pullup resistor to in. an internal delay circuit prevents pok from switching for 50s (typ) after the trip threshold is initially reached. if the part is in shutdown mode, pok is low. power-on reset (max8518 only) the max8518 features a power-on reset (por) output that transitions high 140ms (typ) after the output has risen above 90% of its final value. this open-drain output requires an external pullup resistor to in. if the part is in shutdown mode, falls below 90% of the nominal output voltage, or experiences a short-circuit or thermal fault, por immediately transitions low. figure 1. typical application circuit max8516max8517 max8518 1f 4.7f enable shutdown inin pok (max8517) or por (max8518) en gnd fb outout 100k ? * r1r2 adjustable output *for max8517 and max8518 +1.425v to +3.6v max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators www.maximintegrated.com maxim integrated 7 downloaded from: http:///
operating region and power dissipation the maximum power dissipation depends on the thermal resistance of the ic package and circuit board, the tem - perature difference between the die junction and ambient air, and the rate of airflow. the power dissipated in the device is p = i out x (v in - v out ). the package features an exposed thermal pad on its underside. this pad lowers the thermal resistance of the package by providing a direct heat conduction path from the die to the pcb. additionally, the ground pins (gnd) perform the dual function of providing an electrical connection to system ground and channeling heat away. connect the exposed backside pad and gnd to the system ground using a large pad or ground plane, or multiple vias to the ground plane layer. applications information capacitor selection and regulator stability capacitors are required at the max8516/max8517/ max8518 inputs and outputs for stable operation over the full temperature range and with load currents up to 1a. connect a 1f capacitor between in and ground and a 4.7f capacitor with low equivalent series resistance (esr) between out and ground for 1a output current. the input capacitor (c in ) lowers the source impedance of the input supply. if input-supply source impedance is high, place a larger input capacitor close to in to prevent v in sagging due to load transients. smaller output capacitors can be used for output currents less than 1a. calculate c out as follows: out out(max) c i (1f / 200ma) = noise, psrr, and transient response the max8516/max8517/max8518 are designed to oper - ate with low dropout voltages and low quiescent currents while still maintaining good noise, transient response, and ac rejection (see the typical operating characteristics for a plot of power-supply rejection ratio (psrr) vs. frequency). when operating from noisy sources, improved supply-noise rejection and transient response can be achieved by increasing the values of the input and output bypass capacitors and through passive filtering techniques. the max8516/max8517/max8518 load- transient response graphs (see the typical operating characteristics ) show two components of the output response: a dc shift from the output impedance due to the load current change, and the transient response. a typical transient overshoot for a step change in the load current from 20ma to 1a is 45mv. use larger output ceramic capacitors greater than 4.7f up to 50f to attenuate the overshoot. max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators www.maximintegrated.com maxim integrated 8 chip information transistor count: 2849 process: bicmos downloaded from: http:///
package type package code document no. 10 max u10e+3 21-0109 max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators www.maximintegrated.com maxim integrated 9 package information for the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages . note that a +, #, or - in the package code indicates rohs status only. package drawings may show a different suffix character, but the drawing pertains to the package regardless of rohs status. chip information transistor count: 2849 process: bicmos downloaded from: http:///
revision number revision date description pages changed 0 2/04 initial release 1 4/04 removed future product asterisks for max8517/max8518. updated electrical characteristics and pin description . 1C3, 6 2 9/09 added max8517 automotive package to ordering information . 1 3 4/16 added lead-free designation 1, 9 maxim integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim integrated product. no circuit patent licenses are implied. maxim integrated reserves the right to change the circuitry and speciications without n otice at any time. the parametric values (min and max limits) shown in the electrical characteristics table are guaranteed. other parametric values quoted in this data sheet are provided for guidance. maxim integrated and the maxim integrated logo are trademarks of maxim integrated products, inc. ? 2016 maxim integrated products, inc. 10 max8516/max8517/max8518 1.425v to 3.6v input, 1a, 0.2v dropout ldo regulators revision history for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim integrateds website at www.maximintegrated.com. downloaded from: http:///
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