rev. 10/11/00 as2700/01/02 700ma low dropout voltage regulators with shutdown (preliminary information) features applications ? output current 700ma at 3.3v and 5v ? battery powered systems ? internal short circuit current limit ? cordless telephones ? dropout voltage 0.5v at 700ma output ? automotive electronics ? extremely tight load and line regulation ? portable/ palm top / notebook computers ? very low temperature coefficient ? portable consumer equipment ? mirror image insertion protection ? portable instrumentation ? unregulated dc input can withstand -20v reverse battery ? smps post-regulator and +60v positive transients ? voltage reference ? direct replacement for lm2937 socket product description the as2700/01/02 are a low power positive voltage regulators. the as2700/01/02 offers 700ma output current with a dropout voltage of only 0.5v and over temperature dropout is up to 1v. the quiescent current is 10ma at differential output of 5v and output current of 700ma. a higher quiescent current can exist when the device is in dropout mode (v in -v out 3v). the regulator will automatically shut down to protect both the internal circuits and the load. this device also features short circuit and thermal overload protection. the as2700/01/02 is offered in 3 and 5 pin to-220, to-263 and 3-pin sot-223 packages compatible with other 5v and 3.3v regulators, to-263 and 3-pin sot-223. the device is offered in standard output voltages of 5v and 3.3v as well as in adjustab le output regulator. ordering information to-220 3 / 5-pin to-263 3 / 5-pin sot-223 3-pin oper. temp. range as2700/01/02yu-x as2700/01/02yt-x as2700ym3-x -40 c to +125 c x= output voltage (x = 3.3v, 5.0v) y = a or blank for adjustable). top view to-263-3 (t) 1 as2700 2 3 to-220-5 (u) front view 5 4 3 2 1 as2701/02 five lead package pin functions: to-263-5 (t) top view 45 as2700/01/02 1 2 3 front view to-220-3 (u) as2700 123 v in gnd v out 1) error 2) input 3) gnd 4) output 5) shutdown as2701 as2702 adjust shutdown gnd input output v in v out gnd sot-223 (m3) top view as2700 13 2 v in v out gnd pin connections
rev. 10/11/00 as2700/01/02 absolute maximum ratings power dissipation..........................................internally limited input supply voltage continuous .................. ....... +12v lead temp. (soldering, 10 seconds) .............................. 260c transient................-20v to +60v feedback input voltage...................................... -1.5v to +30v storage temperature range .........................- 65 to +150c shutdown input voltage..................................... -0.3v to +30v operating junction temperature range ..... -40c to +12 5c error comparator output ................................... -0.3v to +30v esd rating .....................................2kv mi n electrical characteristics at v in = v o + 5v, i o = 700ma, c o = 10 f, unless otherwise specified. limits in boldface type apply over the entire operating temperature range. all other specifications are t a = 25 c. parameter conditions (note 2) typ. as2700/01/02a min max as2700/01/02b min max units 3.3v version output voltage -40 c tj +125 c 1ma i l 500ma 3.3 3.3 3.267 3.217 3.333 3.382 3.234 3.185 3.366 3.415 v 5v version output voltage -40 c tj +125 c 1ma i l 700ma 5.0 5.0 4.950 4.880 5.050 5.120 4.900 4.870 5.100 5.130 v all voltage options output voltage temperature coefficient (note1) 20 100 150 ppm/ c line regulation (note 3) 6v v in 30v (note4) 0.03 0.1 0.40 0.20 0.80 %max load regulation (note 3) i l = 1 to 700 i l = 0.1 to 1ma 0.04 0.20 0.30 0.30 0.50 %max dropout voltage (note 5) i l = 1ma i l = 700ma 60 375 100 150 400 500 100 150 400 500 mv ground current i l = 1ma i l = 700ma 100 4.5 15 20 150 180 2 2.5 14 16 20 22 150 180 2 2.5 14 16 20 22 a ma current limit v out = 0 700 800 700 800 ma thermal regulation 0.05 0.2 0.2 %/w output noise, 10hz to 100khz il = 100ma c l = 2.2f c l = 33f 400 200 1.0 0.60 1.0 0.60 v vrms adjustable versions only reference voltage over temperature (note 6) 1.235 1.210 1.200 1.185 1.260 1.270 1.285 1.200 1.980 1.185 1.270 1.272 1.285 v feedback pin bias current 20 40 60 60 80 na reference voltage temperature coefficient (note 7) 50 ppm/ c feedback pin bias current temperature coefficient 0.1 na/ c
rev. 10/11/00 as2700/01/02 electrical characteristics at v in = v o + 5v, i o = 700ma, c o = 22 f, unless otherwise specified. limits in boldface type apply over the entire operating temperature range. all other specifications are t a = 25 c . parameter conditions typ. as2700/01/02a min max as2700/01/02b min max units error comparator output leakage current v oh = 30v 0.01 1.00 2.00 1.00 2.00 a output low voltage vin = 4.5v iol = 400a 150 250 400 250 400 mv upper threshold voltage (note 8) 60 40 25 40 25 mv lower threshold voltage (note 8) 75 95 140 95 140 mv hysteresis (note 8) 15 mv shutdown input input logic voltage low (regulator on) high (regulator off) 2.0 0.7 2.0 0.7 v shutdown pin input current vs = 2.4v vs = 30v 30 450 50 100 600 750 90 150 800 1000 a regulator output current in shutdown 3 10 20 15 25 a note 1: output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range. note 2: unless otherwise specified all limits are guaranteed for t j = 25 c, v in = 6v, i l = 100 a and c l = 1 f. additional conditions for the 8-pin versions are feedback tied to 5v tap and output tied to output sense (v out = 5v) and v shutdown 0.8v. note 3: regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. changes in output voltag e due to heating effects are covered under the specification for thermal regulation. note 4 : line regulation for the as2700/01/02 is tested at 150 c for i l = 1 ma. for i l = 100 a and t j = 125 c, line regulation is guaranteed by design to 0.2%. see typical performance characteristics for line regulation versus temperature and load current. note 5: dropout voltage is defined as the input to output differential at which the output voltage drops 100 mv below its nominal val ue measured at 1v differential at very low values of programmed output voltage, the minimum input supply voltage of 2v ( 2.3v over temperature) must be taken int o account. note 6: v ref v out (vin - 1v), 2.3 vin 30v, 100 a i l 250 ma, t j t jmax . note 7: comparator thresholds are expressed in terms of a voltage differential at the feedback terminal below the nominal reference v oltage measured at 6v input. to express these thresholds in terms of output voltage change, multiply by the error amplifier gain = v out /v ref = (r1 + r2)/r2. for example, at a programmed output voltage of 5v, the error output is guaranteed to go low when the output drops by 95 mv x 5v/1.235 = 384 mv. thresholds remain constant as a percent of v out as v out is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% guaranteed. note 8: v shutdown 2v, v in 30v, v out =0, feedback pin tied to 5v tap. note 9: the junction -to-ambient thermal resistance of the to-92 package is 180 c/ w with 0.4? leads and 160 c/ w with 0.25? leads to a pc board. the thermal resistance of the 8-pin dip package is 105 c/w junction-to-ambient when soldered directly to a pc board. junction-to-ambient thermal resistance for the soic (s) package is 160 c/w. feedback input output unregulated dc shutdown ground error ______ 5v tap sense 5v @ 700ma max to cmos or ttl reference error detection comparator error amplifier 1.23v from cmos or ttl + + + + + + 60 mv ? .. 60k 330k 180k ? .. ? .. .. 1 f _ _ as2700/01/02 block diagram
rev. 10/11/00 as2700/01/02 application hints external capacitors the stability of the as2700/01/02 requires a 10 f or greater capacitor between output and ground. oscillation could occur without this capacitor. most types of tantalum or aluminum electrolytic works fine here. for operations below -25 c solid tantalum is recommended since the many aluminum types have electrolytes that freeze at a bout -30 c. the esr of about 5 ? or less and resonant frequency above 500 khz are the most important parameters in the value of the capacitor. the capacitor value may be increased without limit. at lower values of output current, less output capacitance is required for stability. for the currents below 10ma the value of the capacitor can be reduced to 22 f and 0.15 f for 1ma. more output capacitance is needed for the 8-pin version at voltages below 5v since it runs the error amplifier at lower gain. at worst case 22 f or greater must be used for the condition of 750ma load at 1.23v output. the as2700/01/02, unlike other low dropout regulators will remain stable and in regulation with no load in addition to the internal voltage divider. this feature is especially important in applications like cmos ram keep-alive. when setting the output voltage of the as2700/01/02 version with external resistors, a minimum load of 5ma is recommended. if there is more than 10 inches of wire between the input and the ac filter capacitor or if a battery is used as the input then a 1 a tantalum or aluminum electrolytic capacitor should be pl aced from the i nput to the ground. error detection comparator output the comparator produces a logic low output whenever the as2700/01/02 output falls out of regulation by more than around 5%. this is around 75mv offset divided by the 1.235 reference voltage. this trip level remains 5% below normal regardless of the programmed output voltage of the regulator. figure 1 shows the timing diagram depicting the error signal and the regulator output voltage as the as2700/01/02 input is ramped up and down. the error signal becomes low at around 1.3v input, and goes high around 5v input (input voltage at which vout = 4.75 ). since the as2700/01/02?s dropout voltage is load dependent, the input voltage trip point (around 5v) will vary with the load current. the output voltage trip point (approx. 4.75v) does not vary with load. the error comparator has an open-collector output, which requires an external pull-up resistor. depending on the system requirements the resistor may be returned to 5v output or other supply voltage. in determining the value of this resistor, note that the output is rated to sink 250 a, this value adds to battery drain in a low battery condition. suggested values range from 100k to 1m ? . if the output is unused this resistor is not required. programming the output voltage of as2700/01/02 the as2700/01/02 may be programmed for any output voltage between its 1.235v reference and its 30v maximum rating . as seen in figure 2, an external pair of resistors is required. refer to the below equation for the programming of the output voltage: v out = v ref (1 + r 1 \ r 2 )+ i fb r 1 the v ref is 1.235 and i fb is the feedback bias current, nominally -20 na. the minimum recommended load current of 1 a forces an upper limit of 1.2 m ? on value of r 2 . if no load is presented the i fb produces an error of typically 2% in v out , which may be eliminated at room temperature by trimming r 1 . to improve the accuracy choose the value of r 2 = 100k this reduces the error by 0.17% and increases the resistor program current by 12 a. since the as2700/01/02 typically draws 100 a at no load with shutdown open-circuited this is a small price to pay reducing output noise it may be an advantage to reduce the ac noise present at the output. one way is to reduce the regulator bandwidth by increasing the size of the output capacitor. this is the only way that noise can be reduced on the 3 lead as2700/01/02 but is relatively inefficient, as increasing the capacitor from 1 f to 220 f only decreases the noise from 430 v to 160 v rms for a 100 khz bandwidth at 5v output. noise could also be reduced fourfold by a bypass capacitor across r 1 , since it reduces the high frequency gain from 4 to unity. pick c bypass ? 1 / 2 r 1 200 hz or choose 0.01 f. when doing this, the output capacitor must be increased to 3.3 f to maintain stability. these changes reduce the output noise from 430 v to 100 v rms for a 100 khz bandwidth at 5v output. with the bypass capacitor added, noise no longer scales with output voltage so that improvements are more dramatic at higher output voltages. + + + + 4.75v output voltage error* _______ input voltage 1.3v 5.0v figure 1. error output timing _______ * see application info. as2702 fig.2 adjustable voltage regulator v in v out gnd adj shutdown
rev. 10/11/00 as2700/01/02 to-263-5l (t) 0.405 0.005 0.055 (1.397) 0.356 0.005 (10.287 0.127) (9.042 0.127) (15.24 0.635) 0.600 0.025 (1.702 0.127) 0.067 0.005 (0.813 0.076) 0.032 0.003 0.176 0.005 (4.470 0.127) 0.050 0.002 (1.270 0.051) 0.015 + - 0.003 0 8 (0.381 0.074) + - 0.100 0.010 (2.540 0.254)
rev. 10/11/00 as2700/01/02 to-263-3l (t) 0.103 bsc 0.050 (1.270) 0.600 + - 0.025 0.405 0.005 0.055 (1.397) (10.287 0.127) 0.356 0.005 (9.042 0.127) (15.24 0.635) (2.616) 0.032 + - 0.001 (0.813 0.025) + - 0.176 0.005 0.050 0.002 0.015 + - 0.003 0 8 (0.381 0.074) + - 0.100 0.010 (2.540 0.254) (4.470 0.127) (1.270 0.051)
rev. 10/11/00 as2700/01/02 to-220-3l (u) 0.408 0.013 (10.36 0.33) 0.110 0.010 (2.794 0.254) 0.250 0.010 (6.350 0.254) 0.151d 0.002 (3.835 d 0.051) 0.180 0.005 (4.572 0.127) 0.050 0.002 (1.270 0.051) 0.340 0.010 (8.636 0.254) 0.150 min (3.81 min) 0.410 (10.41) 0.100 0.010 (2.540 0.254) 0.032 0.005 (0.813 0.127) 0.540 0.015 (13.720 0.381) 0.050 typ (1.27 typ) 0.200 0.010 (5.080 0.254) 0.015 0.010/-0.002 (0.381 0.254/-0.051) 0.015 0.010/-0.015 (2.667 0.254/-0.381) 1.020 0.015 (25.910 0.381) seating plane tapered 1 o 2 sides 7 o typ.
rev. 10/11/00 as2700/01/02 to-220-5l (u) 0.108 + - 0.005 (2.74 + - 2.74) 0.400 + - 0.005 (10.16 + - 0.13) 0.150 d + - 0.005 (3.81d + - 0.13) 0.175 + - 0.005 (4.45 + - 0.13) 0.050 + - 0.005 (1.27 + - 0.13) 0.250 + - 0.005 (6.35 + - 0.13) 0.590 + - 0.005 (14.99 + - 0.13) seating plane 0.547 + - 0.005 (13.89 + - 0.005) 0.067 + - 0.005 (1.70 + - 0.127) 0.268 ref (6.81 ref) 0.268 ref 0.032 + - 0.005 (0.81 + - 0.13) 0.015 + - 0.005 (0.38 + - 0.13) 0.105 + - 0.005 (2.67 + - 0.13) 1.137 ref (28.88 ref) 7 typ.
rev. 10/11/00 as2700/01/02 sot-223-3l (m3) 0.116 0.124 0.146 0.130 0.295 0.264 0.041 0.033 0.0905 nom 0.181 nom 0.264 0.248 0.0040 0.0008 0.033 0.025 0.146 0.130 10 c max 0.014 0.010 10 c 16 c 10 c 16 c 16 c
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