general description the max16999 linear regulator operates from a 2.5v to 5.5v input voltage and delivers 100ma continuous load current with a low quiescent current typically around 13?. the output voltage is preset to internally trimmed voltages in the 0.5v to 3.3v range (see the selector guide ). an active-low, open-drain reset output remains low for a programmable timeout delay after the output voltage reaches regulation. the reset timeout is pro- grammed by an external capacitor connected to cres. this device also features logic-controlled shutdown, and short-circuit and thermal-overload protection. the typical applications are multimedia, telematics, and motor control microcontrollers (?s) with always-on requirements. the max16999 is used as a parallel, low- quiescent supply to power the core or interrupt section of ?s during sleep mode. it can also be used to sup- ply a timer or memory during ? shutoff. the adjustable por delay assists with power-supply sequencing. applications industrial sdram power supplies keep-alive timers handheld/portable devices features ? preset 0.5v to 3.3v output voltage range ? up to 100ma output current at t a = +125? ? 13 a quiescent current ? logic-controlled enable ? adjustable por delay flag ? short to gnd protection on reset timer ? used in parallel with high-current supply of equal voltages ? aec-100 qualification request ? thermal-overload and short-circuit protection ? tiny 8-pin ?ax package with exposed pad max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications ________________________________________________________________ maxim integrated products 1 input 2.5v to 5.5v output 0.5v to 3.3v on c in 1 f off to controller gnd in out cres reset en ep logic supply max16999 c out 4.7 f c cres 15nf typical operating circuit 19-4114; rev 0; 4/08 for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. ordering information * insert the desired two-digit suffix (see the selector guide) into the blanks to complete the part number. contact the factory for other output voltages or other package options. + denotes a lead-free package and rohs compliant. ** ep = exposed pad. part* temp range pin-package MAX16999AUA_ _+ -40? to +125? 8 ?ax-ep** 1 2 3 4 + 8 7 6 5 in in en gnd *exposed pad * reset cres out out max16999 max top view pin configuration selector guide appears at end of data sheet. ?ax is a registered trademark of maxim integrated products, inc.
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications 2 _______________________________________________________________________________________ absolute maximum ratings dc electrical characteristics (for devices with v out 1.5v, v in = 3.3v. for devices with v out > 1.5v, v in = 5v. en = in, t j = -40? to +125?, c in = 1?, c out = 4.7?, c cres = 1000pf, unless otherwise noted. typical values are at t a = +25?.) (note 1) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. in, reset to gnd .................................................-0.3v to +6.0v out, cres, en to gnd ..............................-0.3v to (v in + 0.3v) output short-circuit duration.....................................continuous continuous power dissipation (t a = +70?) (note 1) (derate 10.3mw/? above +70?) 8-pin ?ax (single-layer pcb) ..................................824.7mw (derate 12.9mw/? above +70?) 8-pin ?ax (multilayer pcb)....................................1030.9mw package junction-to-case thermal resistance ( jc ) ......4.8?/w package junction-to-ambient thermal resistance ( ja ) (single-layer pcb) ........................................................97?/w package junction-to-ambient thermal resistance ( ja ) (multilayer pcb) ........................................................77.6?/w operating temperature range .........................-40? to +125? junction temperature ......................................................+150? storage temperature range .............................-60? to +150? lead temperature (soldering, 10s) .................................+300? parameter symbol conditions min typ max units in operating voltage v in 2.5 5.5 v in undervoltage-lockout (uvlo) threshold v uvlo v in rising 1.94 2.2 v in uvlo hysteresis 45 mv v out 1.5v, i out = 1ma to 80ma -2.5 +2.5 output-voltage accuracy v in = v out + 2v v out > 1.5v, i out = 1ma to 100ma -2.5 +2.5 % current limit i lim out = gnd 105 150 ma i out = 100? 13 20 ground current i q i out = 100ma 23 ? dropout voltage v in - v out i out = 80ma, v out = 3.3v (note 2) 0.035 0.1 v load regulation v out / i out i out = 1ma to 80ma 0.1 mv/ma v out < 1v, 2.5v < v in < 5.5v 0.4 line regulation v out / v in i out = 80ma v out 1v, (v out + 1.5v) < v in < 5.5v 1.8 mv/v f = 100hz 70 power-supply rejection ratio psrr i out = 10ma, 500mv p-p, v in - v out > 1.5v f = 100khz 40 db note 1: package thermal resistances were obtained using the method described in jedec specifications. for detailed information on packaging thermal considerations, refer to www.maxim-ic.com/thermal-tutorial .
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications _______________________________________________________________________________________ 3 note 2: limits are 100% production tested at t a = +25?. limits over the operating temperature range are guaranteed by design. note 3: dropout voltage is defined as v in - v out when v out is 2% below its value for v in = v out + 2v. dc electrical characteristics (continued) (for devices with v out 1.5v, v in = 3.3v. for devices with v out > 1.5v, v in = 5v. en = in, t j = -40? to +125?, c in = 1?, c out = 4.7?, c cres = 1000pf, unless otherwise noted. typical values are at t a = +25?.) (note 1) parameter symbol conditions min typ max units en standby current i stb en = gnd 0.3 1 a turn-on delay from en = high to v out = 100mv 10 s en h circuit active 70 logic levels en l circuit inactive 30 %v in pullup resistance r en-h v en = 75% v in 120 k pulldown resistance r en-l v en = 25% v in 120 k reset threshold accuracy v res v out falling 79.5 82.5 85.5 %v out threshold hysteresis v res , hyst 2.5 %v out reset open-drain leakage reset = high impedance, v reset = 5mv 200 na output low voltage v res,ol i load = 250? 100 mv reset t i m e o u t t r s of f cres = gnd 30 80 m s o u tp u t d eg l i t c h t i m e t d e gl i t c h v out < v res 30 ? c r es charge current i cres,up 81012 a discharge current i cres,dn 1ma threshold v cres , thrs reset goes from low to high impedance 575 600 625 mv t h e r m a l p r o t e c t i o n t h er m al - s h u td o w n te m p er a tu r e t s h d n + 1 65 c thermal-shutdown hysteresis t s h d n 1 5 c
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications 4 _______________________________________________________________________________________ typical operating characteristics (for devices with v out < 1.5v, v in = 3.3v. for devices with v out > 1.5v, v in = 5v. en = in, c in = 1?, c out = 4.7?, c cres = 1000pf, t a = + 25?, unless otherwise noted.) output-voltage accuracy vs. load current max16999 toc01 load current (ma) output-voltage accuracy (%) 80 60 40 20 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 -0.5 0 100 v out = 0.5v v out = 3.3v v out = 1v output voltage vs. input voltage max16999 toc02 input voltage (v) output voltage (v) 5.0 4.5 4.0 3.5 3.0 0.995 0.996 0.997 0.998 0.999 1.000 1.001 1.002 1.003 1.004 0.994 2.5 5.5 i out = 0.1ma i out = 50ma i out = 100ma i out = 1ma output-voltage accuracy vs. temperature max16999 toc03 temperature ( c) output-voltage accuracy (%) 100 50 0 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 -0.5 -50 150 i out = 0.1ma i out = 50ma i out = 100ma i out = 1ma v out = 1v ground-pin current vs. load current max16999 toc04 load current (ma) ground-pin current ( a) 80 60 20 40 5 10 15 20 30 25 35 40 0 0100 v out = 0.5v v out = 3.3v v out = 1v ground-pin current vs. input voltage max16999 toc05 input voltage (v) ground-pin current ( a) 5 4 3 2 1 5 10 15 20 25 30 35 40 45 50 0 06 i out = 0.1ma i out = 50ma i out = 100ma i out = 1ma v out = 0.5v ground-pin current vs. temperature max16999 toc06 temperature ( c) ground-pin current ( a) 125 100 75 50 25 0 -25 5 10 15 20 25 30 0 -50 150 i out = 0.1ma i out = 50ma i out = 100ma i out = 1ma v out = 1v current limit vs. input voltage max16999 toc07 input voltage (v) current limit (ma) 5.0 4.5 3.0 3.5 4.0 135 140 145 150 155 160 165 170 130 2.5 5.5 dropout voltage vs. load current max16999 toc08 load current (ma) dropout voltage (ma) 125 100 75 50 25 10 20 30 40 50 60 70 80 90 100 0 0 150 v out = 3.3v power-supply rejection ratio vs. frequency max16999 toc09 frequency (khz) psrr (db) 100 10 0.1 1 10 20 30 40 50 60 70 80 0 0.01 1000 v out = 0.5v, i out = 10ma
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications _______________________________________________________________________________________ 5 line-transient response max16999 toc10 200 s/div v in v out 3.5v 4v 100mv/div ac-coupled v out = 0.5v line-transient response near dropout max16999 toc11 200 s/div v in v out 0.6v 1.6v 200mv/div ac-coupled v out = 0.5v typical operating characteristics (continued) (for devices with v out < 1.5v, v in = 3.3v. for devices with v out > 1.5v, v in = 5v. en = in, c in = 1?, c out = 4.7?, c cres = 1000pf, t a = + 25?, unless otherwise noted.) shutdown response max16999 toc14 100 s/div v en v out 0 0 5v 1v v out = 1v, i out = 50ma reset/enable response max16999 toc15 400 s/div v en v out 0 0 5v 0 5v 1v v out = 1v, i out = 50ma, c cres = 15,000pf v reset load-transient response max16999 toc12 200 s/div i out v out 0 50ma/div 100mv/div ac-coupled v out = 3.3v load-transient response near dropout max16999 toc13 200 s/div i out v out 0 50ma/div 100mv/div ac-coupled v out = 3.3v, v in = v out + 50mv
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications 6 _______________________________________________________________________________________ 6 _______________________________________________________________________________________ pin description pin name function 1, 2 out regulator output. bypass out to gnd with a 4.7? ceramic capacitor. out becomes high impedance when en is low. 3 cres por timer. bypass cres to gnd with a ceramic capacitor to define por timing (see the por timer section). 4 reset open-drain, active-low reset output. reset is high impedance when output is in regulation or if the ic is in shutdown. reset is pulled low when v out drops below 82.5% (typ) of its nominal voltage. 5 gnd ground. connect gnd to a large circuit board ground plane and directly to the exposed paddle. 6en active-high enable input. drive en low to place the regulator in standby mode. drive en high or connect to in for normal operation. 7, 8 in regulator input. bypass in to gnd with at least a 1? ceramic capacitor. ?p exposed paddle. connect ep to a large pad or circuit board ground plane to maximize power dissipation. ep serves as a heatsink. line/reset response max16999 toc16 2ms/div v in v out 0 0 2v/div 0 5v 500mv/div v out = 0.5v, i out = 50ma, c cres = 15,000pf v reset cres pullup current vs. temperature max16999 toc17 temperature ( c) cres pullup current ( a) 125 100 50 75 0 25 -25 2 4 6 8 10 12 14 16 18 20 0 -50 150 v out = 1v, c cres = 15,000pf reset timeout vs. cres capacitance max16999 toc18 cres capacitance (nf) reset timeout (ms) 400 300 200 100 5 10 15 20 25 30 0 0500 short-circuit response max16999 toc19 200 s/div v out i out 0 0 5v 0 5a 5v v out = 3.3v v reset typical operating characteristics (continued) (for devices with v out < 1.5v, v in = 3.3v. for devices with v out > 1.5v, v in = 5v. en = in, c in = 1?, c out = 4.7?, c cres = 1000pf, t a = + 25?, unless otherwise noted.)
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications _______________________________________________________________________________________ 7 _______________________________________________________________________________________ 7 in error amplifier v ref 0.825 x v ref v cres,thrs 100k out cres ep reset en gnd max16999 por comparator cres comparator 20 s deglitch logic control i cres,up (10 a) i cres,down (10ma) counter (100ms) figure 1. block diagram
detailed description the max16999 is a low-quiescent-current linear regula- tor designed for applications requiring high reliability, such as automotive applications. this device can supply loads up to 100ma and is available in factory-preset out- put voltages from 0.5v to 3.3v (see the selector guide ). as illustrated in figure 1, the max16999 linear regulator consists of a reference, an error amplifier, a p-channel mosfet pass transistor, and an internal feedback volt- age-divider. a power-on reset section signals if the out- put voltage has come out of regulation. the reset signal timeout is defined by the charging time of an external capacitor attached to cres. to increase system reliability, the max16999 features a por reset timeout along with overcurrent and overtem- perature protection. a power-on reset timeout guaran- tees startup even with a faulty timing capacitor. parameters are guaranteed up to +125? junction tem- perature. the en signal is latched in its last state even if the signal line becomes disconnected. logic-controlled enable the max16999 provides a logic-enable input (en). for normal operation drive en to logic-high. when en is driven high, the linear regulator starts to regulate by increasing the output voltage up to the preset value. to disable the device, drive en low to set out to high impedance?his enables a pulldown current from cres to discharge the capacitor. once the device is disabled, the input supply current reduces to less than 0.3?. the en input is latched into its last state by a 120k internal resistor. to change state, the latch needs to be overridden. when en is low, the reset output is high impedance. por timer once the output voltage rises above the threshold v res , two internal timers are simultaneously activated. the reset timer is realized by means of a pullup current i cres,up that charges the capacitor connected to cres. as soon as the voltage on c res rises above the thresh- old of 600mv (typ), reset goes high impedance. the internal reset timer is set by the value of the exter- nal capacitance (c cres ). calculate the reset time using the following formula: where c cres is in farads and the delay to gnd is given in seconds. the second timer is an internal fault timer and ensures the regulator does not stay off indefinitely because of a fault on cres such as a short. the fault timer runs for a maximum of 100ms. a logic block monitors both inter- nal timers to determine the shortest timeout. if the first timeout is the fault timer, the pullup current is switched off in order to avoid unnecessary current consumption and a resistive pulldown is also activated. if t por_delay exceeds 100ms (typ) the fault timer defines the timeout behavior. current limit once the output voltage reaches regulation, the output current is limited to 150ma (typ). if the output current exceeds the current limit, the output voltage begins to decrease. thermal-overload protection thermal-overload protection limits total power dissipa- tion in the max16999. when the junction temperature exceeds +165?, a thermal sensor turns off the pass transistor, allowing the ic to cool. the thermal sensor turns the pass transistor on again after the junction tem- perature cools by 15?, resulting in a pulsed output during continuous thermal-overload conditions. thermal-overload protection safeguards the max16999 in the event of fault conditions. for continuous opera- tion, do not exceed the absolute maximum junction- temperature rating of +150?. table 1 lists maximum dc output currents (milliamps) that are allowed for operation at t a = +125? without causing thermal shut- down of the max16999. tcxx v a por delay cres _ = 60 10 3 max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications 8 _______________________________________________________________________________________
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications _______________________________________________________________________________________ 9 undervoltage lockout (uvlo) before the max16999 can operate, the input voltage must exceed the uvlo threshold of 2.2v (max) with a 30mv hysteresis. if the input voltage is below the uvlo threshold, out becomes high impedance and en is ignored regardless if it is driven high or low. applications information capacitor selection capacitors are required at the max16999 input and output for stable operation over the full temperature range and with load currents up to 100ma. connect a 1? ceramic capacitor between in and gnd and a 4.7? ceramic capacitor between out and gnd. the input capacitor (c in ) lowers the source impedance of the input supply. use larger output capacitors to reduce noise and improve stability and power-supply rejection. the output capacitor? equivalent series resistance (esr) affects stability and output noise. use output capacitors with an esr of 30m or less to ensure stability and optimize transient response. surface-mount ceramic capacitors have very low esr and are commonly available in values up to 10?. connect c in and c out as close to the max16999 as possible to minimize the impact of the pcb trace induc- tance. using max16999 in parallel with another supply the max16999 can be used in parallel with another supply of equal voltage (see figure 2). the circuit shows a typical low-power solution for a ?. 4v to 36v 3.3v, 1a low-iq interface supply 1.2v, 3a core supply to c 1.2v low-iq core bypass max1745 max8693 max16999 figure 2. low-quiescent ? supply solution table 1. output currents at t a = +125? single-layer board multilayer board v out (v) v in = 3.3v (ma) v in = 5v (ma) v in = 5v (ma) 0.5 92 57 72 0.6 95 59 73 0.7 99 60 75 0.8 100 61 77 0.9 100 63 79 1.0 100 64 81 1.1 100 66 83 1.2 100 68 85 1.5 100 74 92 1.8 100 81 100 2.5 100 100 100 3.3 100 100 100
max16999 ultra-low output voltage, low-quiescent-current linear regulator for high-temperature applications maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 10 ____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2008 maxim integrated products is a registered trademark of maxim integrated products, inc. heaney chip information process: bicmos selector guide suffix v out (v) top mark 05* 0.5 apm 06 0.6 apn 07 0.7 apo 08 0.8 app 09 0.9 apq 10* 1.0 apr 11 1.1 aps 12 1.2 apt 13 1.3 apu 15 1.5 apv 18 1.8 apw 25 2.5 apx 33* 3.3 apy * bold indicates a standard value. for other values, contact fac- tory for availability. (nonstandard options require a 5k mini- mum quantity order). package information for the latest package outline information, go to www.maxim-ic.com/packages . package type package code document no. 8 ?ax-ep u8e+2 21-0107
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