MIC29302HWU high-current low-dropout regulators super eta pnp is a trademark of micrel, inc. micrel inc. ? 2180 fortune drive ? san jose, ca 95131 ? usa ? tel +1 (408) 944-0800 ? fax + 1 (408) 474-1000 ? http://www.micrel.com november 11, 2013 revision 1.0 general description the MIC29302HWU is a high current, high accuracy, low- dropout voltage regulators. using micrel's proprietary super eta pnp ? process with a pnp pass element, these regulators feature 350mv to 425mv (full load) typical dropout voltages and very low ground current. designed for high current loads, these devices also find applications in lower current, extremely low dropout-critical systems, where their tiny dropout volt age and ground current values are important attributes. the MIC29302HWU is fully pr otected against overcurrent faults, reversed input polarity, reversed lead insertion, over-temperature operatio n, and positive and negative transient voltage spikes. five pin fixed voltage versions feature logic level on/off control and an error flag which signals whenever the output falls out of regulation. flagged states include low input voltage (dropout), output current limit, over-temperature shutdown, and extremely high voltage spikes on the input. the enable pin may be tied to vin if it is not required for on/off control. the MIC29302HWU is available in a 5- pin surface mount to-263 (d 2 pak) package. for applications with input voltage 6v or below, see mic37xxx ldos. data sheets and support documentation can be found on micrel?s web site at: www.micrel.com . features ? 3a current capability ? low-dropout voltage ? low ground current ? accurate 1% guaranteed tolerance ? extremely fast transient response ? reverse-battery and ?load dump? protection ? zero-current shutdown mode ? error flag signals output out-of-regulation ? also characterized for smaller loads with industry- leading performance specifications applications ? battery-powered equipment ? high-efficiency ?green? computer systems ? automotive electronics ? high-efficiency linear power supplies ? high-efficiency post-regulator for switching supply typical application
micrel, inc. MIC29302HWU november 11, 2013 2 revision 1.0 ordering information part number junction temp. range voltage current package MIC29302HWU ?40 to +125c adjustable 3.0a 5-pin to-263 pin configuration 5-pin to-263 (d 2 pak) adjustable voltage MIC29302HWU pin description pin number pin name 1 en: enable, cmos compatible control input. logic high = enable, logic low = shutdown. 2 in: input power, supplies the curr ent to the output power device 3, tab gnd: tab is also connected in ternally to the ic?s ground on d-pak. 4 out: output, the regulator output voltage 5 adj: adjustable regulator feedback input that connects to the resistor voltage divider that is placed from output to gnd in order to set the output voltage.
micrel, inc. MIC29302HWU november 11, 2013 3 revision 1.0 absolute maximum ratings (1) input supply voltage (v in ) (1) ........................... ?20v to +60v enable input voltage (v en ) ................................ ?0.3v to v in lead temperature (solder ing, 5sec.) ......................... 260c power dissipation ..................................... internally limited storage temperature rang e .................... ?65c to +150c esd rating ................................................................. note 3 operating ratings (2) operating junction temper ature .............. ?40c to +125c maximum operating in put voltage ................................ 26v package thermal resistance to-263 ( jc ) ......................................................... 2c/w to-263 ( ja ) .................................................... 26.2c/w electrical characteristics (4, 13) v in = v out + 1v; i out = 10ma; t j = 25c. bold values indicate ?40c t j +125c, unless noted. parameter condition min. typ. max. units output voltage i out = 10ma ?1 1 % 10ma i out i fl , (v out + 1v) v in 26v (5) ?2 2 line regulation i out = 10ma, (v out + 1v) v in 26v 0.06 0.5 % load regulation v in = v out + 1v, 10ma i out 1.5a (5,9) 0.2 1 % ? v o ? t output voltage (9) temperature coefficient. 20 100 ppm/c dropout voltage ( ? v out = ? 1% (6) ) i out = 100ma 80 175 mv i out = 1.5a 250 i out = 3a 370 600 ground current (v in = v out + 1v) i out = 750ma 8 ma i out = 1.5a, 10 35 i out = 3a 37 ground pin current at dropout v in = 0.5v less than specified v out , i out = 10ma 1.7 ma current limit v out = 0v (7) 4.5 5.0 a e n , output noise voltage (10hz to 100khz) i l = 100ma 260 v (rms) ground current in shutdown v en = 0.4v 20 a reference voltage 1.228 1.215 1.240 1.252 1.265 v reference voltage v ref v out (v in ? 1v), 2.3v v in 26v, 10ma < i l 3a, t j t jmax 1.203 1.277 v adjust pin bias current 40 80 120 na reference voltage temperature coefficient note 10 20 ppm/c adjust pin bias current temperature coefficient 0.1 na/c input logic voltage low (off) high (on) 2.4 0.8 v
micrel, inc. MIC29302HWU november 11, 2013 4 revision 1.0 electrical characteristics continued (4, 13) v in = v out + 1v; i out = 10ma; t j = 25c. bold values indicate ?40c t j +125c, unless noted. parameter condition min. typ. max. units enable pin input current v en = 26v 100 600 750 a v en = 0.8v 0.8 2 4 regulator output current in shutdown note 12 10 500 a notes: 1. maximum positive supply voltage of 60v must be of limited duration (<100msec) and duty cycle ( 1%). the maximum continuous supply voltage is 26v. exceeding the absolute maximu m rating may damage the device. 2. the device is not guaranteed to function outside its operating rating. 3. devices are esd sensitive. handling precautions recommended. 4. specification for packaged product only. 5. full load current (i fl ) is defined as 3a for the mic29302h. 6. dropout voltage is defined as the input-to-output differential when the output voltage drops to 99% of its normal value with v out + 1v applied to v in . 7. v in = v out (nominal) + 1v. for example, use v in = 4.3v for a 3.3v regulator or use 6v for a 5v regulator. employ pulse-testing procedures to pin current. 8. ground pin current is the regulator quiescent current. the tota l current drawn from the source is the sum of the load curren t plus the ground pin current. 9. output voltage temperature coefficient is defined as the wo rst case voltage change divided by the total temperature range. 10. thermal regulation is defined as the change in output voltage at a time t after a change in power dissipation is applied, e xcluding load or line regulation effects. specifications are for a 200ma lo ad pulse at vin = 20v (a 4w pulse) for t = 10ms. 11. comparator thresholds are expressed in terms of a voltage di fferential at the adjust 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 95mv x 5v/1.240v = 384m v. thresholds remain constant as a percent of v out as v out is varied, with the dropout warning occurring at typically 5% below nominal, 7.7% guaranteed. 12. v en 0.8v and v in 26v, v out = 0. 13. when used in dual supply systems where the regulator load is returned to a negative supply, the output voltage must be diod e clamped to ground
micrel, inc. MIC29302HWU november 11, 2013 5 revision 1.0 typical characteristics
micrel, inc. MIC29302HWU november 11, 2013 6 revision 1.0 typical characteristics (continued)
micrel, inc. MIC29302HWU november 11, 2013 7 revision 1.0 functional diagram
micrel, inc. MIC29302HWU november 11, 2013 8 revision 1.0 application information the MIC29302HWU is a high-performance low-dropout voltage regulator suitable for moderate to high-current voltage regulator applications. the 350mv to 425mv typical dropout voltage at full load makes it especially valuable in battery powered systems and as high efficiency noise filters in ?post-regulator? applications. unlike older npn-pass transistor designs, where the minimum dropout voltage is limited by the base-emitter voltage drop and collector-emitter saturation voltage, dropout performance of the pnp output of these devices is limited merely by the low v ce saturation voltage. a trade-off for the low-dropout voltage is a varying base driver requirement. but micrel?s super ?eta pnp ? process reduces this drive requirement to merely 1% of the load current. the MIC29302HWU regulator is fully protected from damage due to fault conditions. current limiting is provided. this limiting is linear; output current under overload conditions is constant. thermal shutdown disables the device when the die temperature exceeds the 125c maximum safe operating temperature. line transient protection allows device (and load) survival even when the input voltage spikes between ?20v and +60v. when the input voltage exceeds approximately 40v, the over voltage sensor disables the regulator. the output structure of these regulators allows voltages in excess of the desired output voltage to be applied without reverse current flow. the MIC29302HWU versions offer a logic level on/off control: when disabled, the devices draw nearly zero current. figure 1. linear regulators require only two capacitors for operation thermal design linear regulators are simple to use. the most complicated design parameters to consider are thermal characteristics. thermal design requires the following application-specific parameters: ? maximum ambient temperature, t a ? output current, i out ? output voltage, v out ? input voltage, v in first, we calculate the power dissipation of the regulator from these numbers and the device parameters from this datasheet. ? ? out in out d v v 1.01 i p ? ? ?? cs jc d a jmax sa p t t ? ? ? ? ? ? ? eq. 2 : ?? cs jc d a jmax sa p t t ? ? ? ? ? ? ? eq. 2 where tjmax 125c and cs is between 0 and 2c/w. for example, given an expected maximum ambient temperature (ta) of 75 ? c with vin = 3.3v, vout = 2.5v, and iout = 1.5a, first calculate the expected pd using eq. 3: p d =(3.3v?2.5v)1.5a?(3.3v)(0.016a)=1.1472w eq. 3 next, calcualte the junction temperature for the expected power dissipation. t j =( ja p d )+t a =(56 ? c/w1.1472w)+75 ? c =139.24 ? c eq. 4
micrel, inc. MIC29302HWU november 11, 2013 9 revision 1.0 then determine the maximum power dissipation allowed that would not exceed the ic?s maximum junction temperature (125 ? c) without the useof a heat sink by: p d(max) = (t j(max) ?t a )/ ja = (125 ? c?75 ? c)/(56 ? c/w) = 0.893w eq. 5 capacitor requirements for stability and to minimize output noise, a capacitor on the regulator output is necessary. the value of this capacitor is dependent upon the output current; lower currents allow smaller capacitors. the MIC29302HWU is stable with minimum of 100f. this capacitor need not be an expensive low esr type: aluminum electrolytics are adequate. in fact, extremely low esr capacitors may contribute to instability. tantalum capacitors are recommended for systems where fast load transient response is important. where the regulator is powered from a source with high ac impedance, a 0.1f capacitor connected between input and gnd is recommended. this capacitor should have good characteristics to above 250khz. minimum load current the mic29300hwu is specified between finite loads. if the output current below 7ma, leakage currents dominate and the output voltage rises. adjustable regulator design the mic20302hwu allows programming the output voltage anywhere between 1.25v and the 25v. two resistors are used. the resistor values are calculated by ? ? ? ? ? ? ? ? ? ? ? 1 1.240 v r r out 2 1 eq 6: ? ? ? ? ? ? ? ? ? ? ? 1 1.240 v r r out 2 1 eq 6. where v out is the desired output voltage. figure 3 shows component definition. applications with widely varying load currents may scale the resistors to draw the minimum load current required for proper operation (see ?minimum load current? sub-section). enable input MIC29302HWU features an enable (en) input that allows on/off control of the device. special design allows ?zero? current drain when the device is disabled? only microamperes of leakage current flows. the en input has ttl/cmos compatible thresholds for simple interfacing with logic, or may be directly tied to 30v. enabling the regulator requires approximately 20a of current.
micrel, inc. MIC29302HWU november 11, 2013 10 revision 1.0 package information ( error! reference source not found. ) 5-pin to-263 (u) micrel, inc. 2180 fortune drive san jose, ca 95131 usa tel +1 (408) 944-0800 fax +1 (408) 474-1000 web http://www.micrel.com micrel makes no representations or warranties with respect to th e accuracy or completeness of the information furnished in this data sheet. this information is not intended as a warranty and micrel does not assume responsibility for its use. micrel reserves the right to change circuitry, specifications and descriptions at any time without notice. no license, whether expre ss, implied, arising by estoppel or other wise, to any intellectual property rights is granted by this document. except as provided in micrel?s terms and conditions of sale for such products, mi crel assumes no liability whatsoever, and micrel disclaims any express or implied warranty relating to the sale and/or use of micrel products including l iability or warranties relating to fitness for a particular purpose, merchantability, or infringement of an y patent, copyright or other intellectual p roperty right. micrel products are not designed or authorized for use as components in life suppor t appliances, devices or systems where malfu nction of a product can reasonably be expected to result in pers onal injury. life support devices or system s are devices or systems that (a) are in tended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a si gnificant injury to the user. a purchaser?s use or sale of micrel products for use in life support appliances, devices or systems is a purchaser?s own risk and purchaser agrees to fully indemnify micrel for any damages resulting from such use or sale. ? 2013 micrel, incorporated.
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