? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 1 features ? = 450mv dropout @ 500ma ? = designed to operate with ceramic capacitors ? = adjustable output from 1.200v to 3.3v ? = multiple output voltage options (all parts also adjustable externally using resistors) ? = over current and over temperature protection ? = enable pin ? = 1a quiescent current in shutdown ? = low reverse leakage (output to input) ? = full industrial temperature range description the sc1563 is a high performance positive voltage regulator designed for use in applications requiring very low dropout voltage at up to 500 milliamps. since it has superior dropout characteristics compared to regular ldos, it can be used to supply 2.5v on motherboards or 2.8v on peripheral cards from the 3.3v supply with no heatsink. additionally, the sc1563 has a shutdown pin, to further reduce power dissipation while shut down. the sc1563 provides excellent regulation over variations in line, load and temperature. the sc1563 is available as a five terminal fixed or adjustable output voltage device with enable. the device is available in a 5-pin sot-23 package and an 8-pin msop package for higher power dissipation/ lower junction temperature. applications ? = battery powered systems ? = motherboards ? = peripheral cards ? = pcmcia cards device (1)(2)(3) package sc1563isk-x.xtr sot-23-5l sc1563ims-x.xtr msop-8 ordering information notes: (1) where -x.x denotes voltage options. available voltages are: 1.8v, 2.5v, 2.8v, 3.0v, 3.1v and 3.3v. (2) output voltage can be adjusted using external re- sistors, see pin description. (3) only available in tape and reel packaging. a reel contains 2500 devices (msop-8) or 3000 devices (sot-23-5l). tel:805-498-2111 fax:805-498-3804 web:http:// www.semtech.com typical application internally preset output voltage externally set output voltage volts r2 r2) (r1 1.200 vo + = vin shdn vo (x.xv) vin shdn vo u1 sc1563isk-x.x 1 2 3 4 5 shdn gnd adj vo vin c1 c2 u1 sc1563isk-x.x 1 2 3 4 5 shdn gnd adj vo vin c1 c2 r1 r2
? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 2 absolute maximum ratings parameter symbol maximum units input voltage v in 5.5 v power dissipation p d internally limited w thermal resistance junction to ambient msop-8 (1) msop-8 (2) sot-23-5l (1) ja 206 95 256 c/w thermal resistance junction to case msop-8 sot-23-5l jc 39 81 c/w operating ambient temperature range t a -40 to+85 c operating junction temperature range t j -40 to 150 c storage temperature range t stg -65 to 150 c lead temperature (soldering) 10 sec. t lead 300 c esd rating esd 2 kv electrical characteristics unless specified: v shdn = 0v adjustable option (v adj > v th(adj) ): v in = 2.2 to 5.5v and i o = 10a to 500ma fixed options (v adj = gnd): v in = (v o + 0.7v) to 5.5v and i o = 0a to 500ma values in bold apply over the full operating temperature range. parameter symbol test conditions min typ max units vin supply voltage range vin 2.2 5.5 v quiescent current i q v in = 3.3v 100 150 a v in = 5.5v, v shdn = open 0.5 2 a vo output voltage (1) v o v in = v o + 0.7v, i o = 10ma 0.99v o v o 1.01v o v (internal fixed voltage) 0.98v o v o 1.02v o line regulation (1) reg (line) v in = (v o + 0.25v) to 5.5v, i out = 10ma 0.035 0.3 % load regulation (1) reg (load) v in = v o + 0.7v 0.2 0.4 % notes: (1) minimum pad size. (2) 1 square inch of fr-4, double sided, 1oz. minimum copper weight.
? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 3 notes: (1) low duty cycle pulse testing with kelvin connections required. (2) defined as the input to output differential at which the output voltage drops to 1% below the value measured at a differential of 0.7v. (3) required to maintain regulation. voltage set resistors r1 and r2 are usually utilized to meet this requirement. adjustable versions only. (4) guaranteed by design. (5) when v adj exceeds this threshold, the ?sense select? switch disconnects the internal feedback chain from the error amplifier and connects v adj instead. electrical characteristics (cont.) unless specified: v shdn = 0v adjustable option (v adj > v th(adj) ): v in = 2.2 to 5.5v and i o = 10a to 500ma fixed options (v adj = gnd): v in = (v o + 0.7v) to 5.5v and i o = 0a to 500ma values in bold apply over the full operating temperature range. parameter symbol test conditions min typ max units vo (cont.) dropout voltage (2) v d i load = 2ma 1 5 mv 10 i load = 100ma 75 100 mv 150 i load = 250ma 200 300 mv 400 i load = 500ma 450 550 mv 700 minimum load current (3) i o v in = v o + 0.7v 1 10 a current limit i cl 0.50 1.00 a adj reference voltage (1) v ref v in = 2.2v, v adj = v out , i o = 10ma 1.188 1.200 1.212 v 1.176 1.224 adjust pin current (4) i adj v adj = v ref 50 100 na adjust pin threshold (5) v th(adj) 0.10 0.20 0.40 v shdn shutdown pin current i shdn v shdn = 0v, v in = 3.3v 1 10 a shutdown pin threshold v ih v in = 3.3v 1.8 v v il v in = 3.3v 0.4 over temperature protection high trip level t hi 165 c hysteresis t hyst 10 c
? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 4 pin description pin pin number pin function name sot-23-5l msop-8 adj 3 3 this pin, when grounded, sets the output voltage to that set by the internal feed- back resistors. if external feedback resistors are used, the output voltage will be (see application circuit): gnd 2 5-8 reference ground. connect all msop-8 gnd pins. these pins may be used for heatsinking purposes. vin 5 1 input voltage. for regulation at full load, the input to this pin must be between (vo + 0.7v) to 5.5v. minimum vin = 2.2v. vo 4 4 this pin is the power output of this device. shdn 1 2 shutdown input. leaving this pin open turns the regulator off, reducing the quies- cent current to a fraction of its operating value (typically <100na). the device will be enabled if this pin is pulled below 0.4v. connect to gnd if not being used. volts r2 r2) (r1 1.200 vo + = block diagram pin configurations top view sot-23-5l top view msop-8
? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 5 typical application (externally set output voltage) (1)(2) volts r2 r2) (r1 1.200 vo + = notes: (1) maximum vo setpoint is 3.3v. (2) this device is designed to operate with ceramic input and output capacitors. typical applications (internally set output voltage) (2) vin shdn vo (x.xv) u1 sc1563is-x.x 1 2 3 4 5 shdn gnd adj vo vin c1 1uf c2 10uf vin shdn vo u1 sc1563is-x.x 1 2 3 4 5 shdn gnd adj vo vin c1 1uf c2 10uf r1 r2 vin vo (x.xv) shdn u1 sc1563ims-x.x 1 2 3 4 5 6 7 8 vin shdn adj vo gnd gnd gnd gnd c1 1uf c2 10uf
? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 6 applications information introduction the sc1563 is intended for applications such as graphics cards where high current capability and very low dropout voltage are required. it provides a very simple, low cost solution that uses little pcb real estate and typically does not require a heatsink. additional features include an enable pin to allow for a very low power consumption standby mode, and a fully ad- justable output. component selection input capacitor - a 1f ceramic capacitor is recom- mended. this allows for the device being some dis- tance from any bulk capacitance on the rail. addition- ally, input droop due to load transients is reduced, im- proving load transient response. additional capaci- tance may be added if required by the application. output capacitor - a minimum bulk capacitance of 1f, along with a 0.1f ceramic decoupling capacitor is rec- ommended. increasing the bulk capacitance will im- prove the overall transient response. the use of multi- ple lower value ceramic capacitors in parallel to achieve the desired bulk capacitance will not cause stability issues. although designed for use with ce- ramic output capacitors, the sc1563 is extremely toler- ant of output capacitor esr values and thus will also work comfortably with tantalum output capacitors. external voltage selection resistors - the use of 1% re- sistors, and designing for a current flow 10a is rec- ommended to ensure a well regulated output (thus r2 120k ? ). thermal considerations the power dissipation in the sc1563 is approximately equal to the product of the output current and the input to output voltage differential: the absolute worst-case dissipation is given by: for a typical scenario, vin = 3.3v 5%, vout = 2.5v and i o = 500ma, therefore: vin (max) = 3.465v, vout (min) = 2.450v and i q(max) = 1.75ma, thus p d(max) = 0.514w. using this figure, and assuming t a(max) = 85c, we can calculate the maximum thermal impedance allowable to maintain t j 150c: this should be achievable using pcb copper area to aid in conducting the heat away from the device. internal ground/power planes and air flow will also assist in re- moving heat. for higher ambient temperatures addi- tional board copper may be required. use of the avail- able msop-8 package will allow operation at full load where higher input to output voltage differentials exist. () o d i vout vin p ? ? ( ) ) max ( q ) max ( ) max ( o ) min ( ) max ( ) max ( d i vin i vout vin p ? + ? ? = ( ) () w / c 156 514 . 0 70 150 p t t r ) max ( d ) max ( a ) max ( j ) max )( a j ( th = ? = ? = ? marking information msop-8 sot-23-5l 63xx = sc1563, voltage option (example: 6318) yyww = datecode (example: 0008) xxxx = lot number (example: e01102)
? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 7 device outline - sot-23-5 land pattern - sot-23-5
? 2000 semtech corp. 652 mitchell road newbury park ca 91320 very low dropout, low quiescent 500ma regulator sc1563 preliminary - september 11, 2000 8 ecn00-1343 outline drawing - msop-8 land pattern - msop-8
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