general description the max1963a/max1976a low-dropout linear regula-tors operate from a +1.62v to +3.6v supply and deliver a guaranteed 300ma continuous load current with a low 100mv dropout. the high-accuracy (?.5%) output voltage is preset to an internally trimmed voltage in the +0.75v to +3.0v range. an active-low, open-drain reset output remains asserted for at least 2.2ms (max1963a) or 70ms (max1976a) after the output voltage reaches regulation. these devices are offered in thin sot23 and thin dfn packages. an internal pmos pass transistor allows the low supply current to remain independent ofload and dropout voltage, making these devices ideal for portable battery-powered equipment. applications notebook/handheld computerscellular/smart/pda phones dsc, cd/mp3 players pcmcia cards features ? low 1.62v minimum input voltage ? guaranteed 300ma output current ? 2.5% accuracy over load/line/temp ? low 100mv dropout at 300ma load ? 2.2ms (max1963a) or 70ms (max1976a) reset output flag ? supply current independent of load and dropout voltage ? logic-controlled shutdown ? thermal-overload and short-circuit protection ? preset output voltages (0.75v to 3.0v) ? tiny 6-pin thin sot23 package (<1.1mm high) ? tdfn package (<0.8mm high) max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn ___________________________________________________ _____________ maxim integrated products 1 ordering information 19-3684; rev 1; 5/12 for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. part* temp range pin-package m a x1 9 6 3 a e z t_ _ _+ t -40? to +85? 6 thin sot23-6 max1963aett_ _ _+t -40? to +85? 6 td fn -6 3mm x 3m m m ax 1963ae ta_ _ _+ t -40? to +85? 8 td fn -8 2mm x 2m m m a x1 9 7 6 a e z t_ _ _+ t -40? to +85? 6 thin sot23-6 m ax 1976ae tt_ _ _+ t -40? to +85? 6 td fn -6 3mm x 3m m m ax 1976ae ta_ _ _+ t -40? to +85? 8 td fn -8 2mm x 2m m max1976aett_ _ _/v+t -40? to +85? 6 td fn -6 3mm x 3m m top view tdfn 3mm x 3mm i.c. out reset gnd in shdn 123 654 max1963a max1976a gnd reset shdn 1 + + + 6 out in max1963a max1976a thin sot23 23 4 i.c. 5 tdfn 2mm x 2mm n.c. i.c. out n.c. in shdn 123 reset 4 876 gnd 5 max1963a max1976a pin configurations * insert the desired three-digit suffix (see the selector guide) into the blanks to complete the part number. contact the factory for other output voltages. selector guide appears at end of data sheet. max1963amax1976a input 1.62v to 3.6v c out 4.7 f on off in c in 1 f up to300ma shdn gnd output 0.75v to 3.0v logic supply 100k ? to c out reset typical operating circuit + denotes a lead(pb)-free/rohs-compliant package. /v denotes an automotive-qualified part. downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn 2 __________________________________________________ _____________________________________ absolute maximum ratings electrical characteristics (v in = (v out + 0.5v) or 1.8v, whichever is greater; shdn = in, c in = 1?, c out = 4.7?, t a = -40? to +85?, 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 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. in, shdn , reset to gnd .....................................-0.3v to +4.0v out to gnd ................................................-0.3v to (v in + 0.3v) output short-circuit duration.....................................continuous continuous power dissipation (multilayer board, t a = +70?) 6-pin sot23 (derate 9.1mw/? above +70?)............727mw 6-pin tdfn (derate 23.8mw/? above +70?) ......1904.8mw 8-pin tdfn (derate 11.9mw/? above +70?) ........953.5mw operating temperature range ...........................-40? to +85? junction temperature ..................................................... +150? storage temperature range .............................-65? to +150? lead temperature (soldering, 10s) .................................+300? soldering temperature (reflow) .......................................+260? parameter symbol conditions min typ max units input voltage v in 1.62 3.60 v input undervoltage lockout v uvlo v in rising or falling (180mv typical hysteresis) 1.30 1.60 v output voltage accuracy i out = 1ma to 300ma, v in = (v out + 0.5v) to +3.6v -2.5 ?.5 +2.5 % maximum output current i out continuous 300 ma rms current limit i lim v out = 96% of nominal value 450 550 650 ma no load 70 140 i out = 300ma 90 ground current i q dropout (note 2) 70 ? dropout voltage v in - v out i out = 300ma, v out 1.8v (note 2) 100 200 mv load regulation ? v ldr i out = 1ma to 300ma 0.02 0.3 % line regulation ? v lnr v in = (v out + 0.5v) to +3.6v, i out = 1ma -0.15 +0.01 +0.15 % / v output noise 10hz to 100khz, i out = 10ma, v out = 1.5v 86 ? rms psrr f < 1khz, i out = 10ma 70 db shutdown t a = +25? 0.001 1 shutdown supply current i off shdn = gnd t a = +85? 0.01 ? v ih v in = 1.62v to 3.6v 1.4 shdn input logic levels v il v in = 1.62v to 3.6v 0.6 v t a = +25? 1 100 shdn input bias current i shdn v shdn = 0v or 3.6v t a = +85? 5 na turn-on delay from shdn high to out high, v out = 1.8v 90 ? downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn ___________________________________________________ ____________________________________ 3 note 1: limits are 100% production tested at t a = +25?. limits over the operating temperature range are guaranteed by design. note 2: the dropout voltage is defined as v in - v out , when v out is 4% lower than the value of v out when v in = v out + 0.5v. parameter symbol conditions min typ max units reset output reset threshold accuracy v out falling (1.7% typical hysteresis) 80 82.5 85 %v out i reset = 100? 1 100 reset output low voltage v ol v in = +1.0v, i reset = 100? 30 400 mv t a = +25? 0.001 1 reset output high leakage i oh v reset = 3.6v, reset not asserted t a = +85? 0.01 ? max1963a 2.2 3.2 5.5 reset delay t rp from v out high to reset rising max1976a 70 100 160 ms thermal protection thermal-shutdown temperature t shdn +165 ? thermal-shutdown hysteresis ? t shdn 15 ? typical operating characteristics (v in = (v out + 0.5v) or 1.8v, whichever is greater; shdn = in, c in = 1?, c out = 4.7?, t a = +25?, unless otherwise noted.) output voltage accuracy vs. load current max1963/76 toc01 load current (ma) output voltage accuracy (%) 250 200 150 100 50 -0.1 0 0.1 0.2 -0.2 03 0 0 v out = +3.0v v out = +1.5v v out = +0.75v output voltage accuracy vs. input voltage max1963/76 toc02 input voltage (v) output voltage accuracy (%) 3.0 2.6 2.2 1.8 -0.25 0 0.25 0.50 -0.50 1.4 3.4 i out = 300ma i out = 100ma i out = 0ma v out = 1.5v output voltage accuracy vs. temperature max1963/76 toc03 temperature ( c) output voltage accuracy (%) 60 35 10 -15 -1.0 -0.5 0 0.5 1.0 1.5 -1.5 -40 85 v out = +1.5v i out = 0ma, 100ma, 300ma electrical characteristics (continued) (v in = (v out + 0.5v) or 1.8v, whichever is greater; shdn = in, c in = 1?, c out = 4.7?, t a = -40? to +85?, unless otherwise noted. typical values are at t a = +25?.) (note 1) downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn 4 __________________________________________________ _____________________________________ ground-pin current vs. load current max1963/76 toc04 load current (ma) ground-pin current ( a) 100 11 0 0.1 70 80 90 100 110 120 60 0.01 1000 v out = +3.0v v out = +0.75v v out = +1.5v ground-pin current vs. input voltage max1963/76 toc05 input voltage (v) ground-pin current ( a) 3.2 2.8 2.4 2.0 1.6 20 40 60 80 100 120 0 1.2 3.6 i out = 100ma i out = 300ma i out = 0ma v out = 1.5v ground-pin current vs. temperature max1963/76 toc06 temperature ( c) ground-pin current ( a) 60 40 20 0 -20 60 70 80 90 100 110 120 50 -40 80 i out = 100ma i out = 300ma i out = 0ma dropout voltage vs. load current max1963/76 toc07 load current (ma) v dropout (mv) 250 200 150 100 50 40 20 60 80 100 120 0 03 0 0 v out = +1.8v v out = +3.0v power-supply rejection ratio vs. frequency max1963/76 toc08 frequency (khz) psrr (db) 100 10 1 10 20 30 40 50 60 70 80 0 0.1 1000 v out = +0.75v v out = +1.5v v out = +3.0v i out = 10ma line-transient response max1963/76 toc09 40 s/div v in 500mv/div1.5v 10mv/div ac-coupled v out 3.5v typical operating characteristics (continued) (v in = (v out + 0.5v) or 1.8v, whichever is greater; shdn = in, c in = 1?, c out = 4.7?, t a = +25?, unless otherwise noted.) line-transient response near dropout max1963/76 toc10 40 s/div v in 500mv/div1.5v 10mv/div ac-coupled v out 1.8v downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn ___________________________________________________ ____________________________________ 5 load-transient response max1963/76 toc11 20 s/div 200ma/div20mv/div ac-coupled 200ma v out i out 20ma v in = 3.6v v out = 1.5v load-transient response near dropout max1963/76 toc12 20 s/div 200ma/div20mv/div ac-coupled 200ma v out v in = 1.8v v out = 1.5v i out 20ma typical operating characteristics (continued) (v in = (v out + 0.5v) or 1.8v, whichever is greater; shdn = in, c in = 1?, c out = 4.7?, t a = +25?, unless otherwise noted.) shutdown response max1963/76 toc13 100 s/div 1v/div500mv/div v out 00 v shdn max1963/76 toc14 40ms/div 1v/div1v/div 1v/div v out 00 0 v shdn v reset max1976 shutdown/reset response max1963/76 toc15 200ms/div 2v/div1v/div 1v/div v out v in 00 0 v reset max1976 line/reset response downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn 6 __________________________________________________ _____________________________________ pin description pin thin sot23 6-pin tdfn (3mm x 3mm) 8-pin tdfn (2mm x 2mm) name function 16 8i n regulator input. supply voltage can range from +1.62v to +3.6v. bypass inwith at least a 1? ceramic capacitor to gnd (see the capacitor selection and regulator stability section). 2 gnd ground. gnd also functions as a heatsink. solder to a large pad or circuit-board ground plane to maximize sot23 power dissipation. 4 5 gnd ground 35 6 shdn active-low shutdown input. a logic-low reduces supply current to below 1?.connect to in or logic-high for normal operation. 43 4 reset open-drain, active-low reset output. reset rises 3.2ms (max1963a) or 100ms (max1976a) after the output has achieved regulation. reset falls immediately if v out drops below 82.5% of its nominal voltage, or if the max1963a/max1976a are shut down. 5 2 3 i.c. internally connected. leave unconnected or connect to gnd. 6 1 1 out regulator output. sources up to 300ma. bypass with a 4.7? low-esrceramic capacitor to gnd. 2, 7 n.c. no connection. not internally connected. e p ground (tdfns only). ep also functions as a heatsink. solder ep to a large pad or circuit-board ground plane to maximize tdfn power dissipation. max1963amax1976a in gnd shdn shutdown logic thermal sensor ref 82.5% ref timer error amp mos driver with i limit outreset p figure 1. functional diagram downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn ___________________________________________________ ____________________________________ 7 detailed description the max1963a/max1976a are low-dropout, high-accu-racy, low-quiescent-current linear regulators designed primarily for battery-powered applications. these devices supply loads up to 300ma and are available with preset output voltages from +0.75v to +3.0v. as illustrated in figure 1, the max1963a/max1976a consist of a refer- ence, an error amplifier, a p-channel pass transistor, an internal feedback voltage-divider, and a power-good comparator. the reference is connected to the error amplifier, which compares this reference with the feedback voltage and amplifies the difference. if the feedback voltage is lower than the reference voltage, the pass-transistor gate is pulled lower, which allows more current to pass to the output and increases the output voltage. if the feedback voltage is too high, the pass-transistor gate is pulled up, allowing less current to pass to the output. internal p-channel pass transistor the max1963a/max1976a feature a 0.33 ? (r ds(on) ) p-channel mosfet pass transistor. unlike similardesigns using pnp pass transistors, p-channel mosfets require no base drive, which reduces quies- cent current. the pnp-based regulators also waste con- siderable current in dropout when the pass transistor saturates and use high base-drive currents under large loads. the max1963a/max1976a do not suffer from these problems and consume only 90? (typ) of quies- cent current under heavy loads, as well as in dropout. shutdown pull shdn low to enter shutdown. during shutdown, the output is disconnected from the input, an internal 1.5k ? resistor pulls out to gnd, reset is actively pulled low, and the supply current drops below 1?. reset output the max1963a/max1976a microprocessor (?) supervi-sory circuitry asserts a guaranteed logic-low reset during power-up, power-down, and brownout conditions down to +1v. reset asserts when v out is below the reset threshold and remains asserted for at least t rp after v out rises above the reset threshold of regulation. current limit the max1963a/max1976a monitor and control the pass transistor? gate voltage, limiting the output current to450ma (min). if the output exceeds i lim , the max1963a/ max1976a output voltage drops. thermal-overload protection thermal-overload protection limits total power dissipa-tion in the max1963a/max1976a. when the junction temperature exceeds t j = +165?, a thermal sensor turns off the pass transistor, allowing the ic to cool. thethermal sensor turns the pass transistor on again after the junction temperature cools by 15?, resulting in a pulsed output during continuous thermal-overload con- ditions. thermal-overload protection safeguards the max1963a/max1976a in the event of fault conditions. for continuous operation, do not exceed the absolute maximum junction-temperature rating of t j = +150?. operating region and power dissipation the max1963a/max1976a maximum power dissipa-tion depends on the thermal resistance of the ic pack- age and circuit board, the temperature difference between the die junction and ambient air, and the rate of airflow. the power dissipated in the device is p = i out ? (v in - v out ). the maximum allowed power dissi- pation is: p max = (t j(max) - t a ) / ( jc + ca ) where (t j(max) - t a ) is the temperature difference between the max1963a/max1976a die junction andthe surrounding air, jc is the thermal resistance of the junction to the case, and ca is the thermal resistance from the case through the pc board, copper traces,and other materials to the surrounding air. for best heatsinking, expand the copper connected to the exposed paddle or gnd. the max1963a/max1976a deliver up to 300ma and operate with an input voltage up to +3.6v. however, when using the 6-pin sot23 version, high output cur- rents can only be sustained when the input-output dif- ferential voltage is less than 2v, as shown in figure 2. the maximum allowed power dissipation for the 6-pin tdfn is 1.951w at t a = +70?. figure 3 shows that the maximum input-output differential voltage is not limitedby the tdfn package power rating. applications information capacitor selection and regulator stability capacitors are required at the max1963a/max1976ainput and output for stable operation over the full tem- perature range and with load currents up to 300ma. connect a 1? ceramic capacitor between in and gnd and a 4.7? low-esr ceramic capacitor between out and gnd. the input capacitor (c in ) lowers the source impedance of the input supply. use larger outputcapacitors to reduce noise and improve load-transient response, stability, and power-supply rejection. the output capacitor? equivalent series resistance (esr) affects stability and output noise. use output downloaded from: http:///
capacitors with an esr of 30m ? or less to ensure sta- bility and optimize transient response. surface-mountceramic capacitors have very low esr and are com- monly available in values up to 10?. connect c in and c out as close to the max1963a/max1976a as possi- ble to minimize the impact of pc board trace induc-tance. noise, psrr, and transient response the max1963a/max1976a are designed to operatewith low dropout voltages and low quiescent currents in battery-powered systems while still maintaining good noise, transient response, and ac rejection. see the typical operating characteristics for a plot of power- supply rejection ratio (psrr) versus 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 max1963a/max1976a load-transient response (see the typical operating characteristics ) shows two components of the output response: a near-zero dcshift from the output impedance due to the load-current change, and the transient response. a typical transient response for a step change in the load current from 20ma to 200ma is 20mv. increasing the output capacitor? value and decreasing the esr attenuates the overshoot. input-output (dropout) voltage a regulator? minimum input-output voltage difference(dropout voltage) determines the lowest usable supply voltage. in battery-powered systems, this determines the useful end-of-life battery voltage. because the max1963a/max1976a use a p-channel mosfet pass transistor, the dropout voltage is a function of drain-to- source on-resistance (r ds(on) = 0.33 ? ) multiplied by the load current (see the typical operating characteristics ). v dropout = v in - v out = 0.33 ? ? i out the max1963a/max1976a ground current reduces to70? in dropout. max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn 8 __________________________________________________ _____________________________________ maximum output current vs. input voltage (power dissipation limit) (v in - v out ) (v) maximum output current (ma) 2.5 2.0 1.5 1.0 0.5 100 200 300 400 0 03 . 0 maximum recommendedoutput current 6-pin sot23 t a = +85 c t a = +70 c figure 2. power operating regions for the 6-pin sot23: maximum output current vs. input voltage maximum output current vs. input voltage (power dissipation limit) (v in - v out ) (v) maximum output current (ma) 2.5 2.0 1.5 1.0 0.5 100 200 300 400 0 03 . 0 maximum recommendedoutput current 6-pin tdfn 3mm x 3mm t a = +85 c figure 3. power operating regions for the 6-pin tdfn: maximum output current vs. input voltage downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn ___________________________________________________ ____________________________________ 9 chip information process: bicmos max1963a top mark max1976a top mark vout (v) suffix sot tdfn (3mm x 3mm) tdfn (2mm x 2mm) sot tdfn (3mm x 3mm) tdfn (2mm x 2mm) 0.75 075 aacj alm aacu alx 0.85 085 aacv aly 0.90 090 aack aln aacw alz 1.00 100 aacl alo aacx ama 1.10 110 aacm alp aacy amb 1.20 120 aacn alq aacz amc 1.30 130 aaco alr aada amd aad 1.50 150 aacp als aadb ame aae 1.60 160 aadc amf 1.80 180 aacq alt aadd amg 1.85 185 aacr alu aade amh 2.50 250 aacs alv aadf ami 2.85 285 aadg amj 3.00 300 aact alw aadh amk 1.20 120/v auo 1.50 150/v avi 1.80 180/v aup selector guide note: standard voltage options, shown in bold , are available. contact the factory for other output voltages between 1.5v and 4.5v. minimum order quantity is 15,000 units. package information for the latest package outline information and land patterns(footprints), go to www.maxim-ic.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. package type package code outline no. land pattern no. 6 tdfn-ep t633+2 21-0137 90-0058 6 sot-23 z6+1 21-0114 90-0242 8 tdfn-ep t822+1 21-0168 90-0064 downloaded from: http:///
max1963a/max1976a low-input-voltage, 300ma ldo regulators with reset in sot and tdfn maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice 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. 10 ____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2012 maxim integrated products maxim is a registered trademark of maxim integrated products, inc. revision history revision number revision date description pages changed 0 5/05 initial release 1 5/12 added lead-free packaging information to the data sheet, updated selector guide and pin description 1, 6, 9 downloaded from: http:///
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