may 2006 1 mic5211 mic5211 micrel, inc. general description the mic5211 is a dual cap 80ma linear voltage regulator with very low dropout voltage (typically 20mv at light loads), very low ground current (225a at 20ma output current), and better than 3% initial accuracy. this dual device comes in the miniature sot-23-6 package, featuring independent logic control inputs. the cap regulator design is optimized to work with low-value, low-cost ceramic capacitors. the outputs typically require only 0.1f of output capacitance for stability. designed especially for hand-held, battery-powered devices, ground current is minimized using micrels proprietary super ?eta pnp? technology to prolong battery life. when disabled, power consumption drops nearly to zero. key features include sot-23-6 packaging, current limiting, overtemperature shutdown, and protection against reversed battery conditions. the mic5211 is available in dual 1.8v, 2.5v, 2.7v, 2.8v, 3.0v, 3.3v, 3.6v, and 5.0v versions. certain mixed voltages are also available. contact micrel for other voltages. typical application 1 6 2 3 4 0.1f 0.1f enable shutdown enableb v outa mic5211 v in 5 enable shutdown enablea v ou tb features ? stable with low-value ceramic or tantalum capacitors ? independent logic controls ? low quiescent current ? low dropout voltage ? mixed voltages available ? tight load and line regulation ? low temperature coef?cient ? current and thermal limiting ? reversed input polarity protection ? zero off-mode current ? dual regulator in tiny sot-23 package ? 2.5v to 16v input range applications ? cellular telephones ? laptop, notebook, and palmtop computers ? battery-powered equipment ? bar code scanners ? smps post regulator/dc-to-dc modules ? high-ef?ciency linear power supplies mic5211 dual cap 80ma ldo regulator micrel, inc. ? 2180 fortune drive ? san jose, ca 95131 ? usa ? tel + 1 (408) 944-0800 ? fax + 1 (408) 474-1000 ? http://www.micrel.com
mic5211 micrel, inc. mic5211 2 may 2006 pin con?guration ena gnd out b e n b 1 3 4 6 outa l f x x part identification 5 in regulatora voltage code (v outa regulatorb voltage code (v ou tb ) 2 pin 1 index ) pin description pin number pin name pin function 1 ena enable/shutdown a (input): cmos compatible input. logic high = enable, logic low or open = shutdown. 2 gnd ground 3 enb enable/shutdown b (input): cmos compatible input. logic high = enable, logic low or open = shutdown. 4 outb regulator output b 5 in supply input 6 outa regulator output a ordering information part number pb-free part number voltage side a / side b temperature range package standard mark code full manufacturing mark code mic5211-1.8bm6 lfbb mic5211-1.8ym6 lf bb 1.8v 0 o c to +125 o c sot-23-6 mic5211-2.5bm6 lfcc contact factory lf cc 2.5v C 40 o c to +125 o c sot-23-6 mic5211-2.7bm6 lfdd mic5211-2.7ym6 lf dd 2.7v C 40 o c to +125 o c sot-23-6 mic5211-2.8bm6 lfee mic5211-2.8ym6 lf ee 2.8v C 40 o c to +125 o c sot-23-6 mic5211-3.0bm6 lfgg mic5211-3.0ym6 lf gg 3.0v C 40 o c to +125 o c sot-23-6 mic5211-3.3bm6 lfll mic5211-3.3ym6 lf ll 3.3v C 40 o c to +125 o c sot-23-6 mic5211-3.6bm6 lfqq mic5211-3.6ym6 lf qq 3.6v C 40 o c to +125 o c sot-23-6 mic5211-5.0bm6 lfxx mic5211-5.0ym6 lf xx 5.0v C 40 o c to +125 o c sot-23-6 dual-voltage regulators mic5211-1.8/2.5bm6 lfbc mic5211-1.8/2.5ym6 MIC5211-BCYM6 lf bc 1.8v / 2.5v 0 o c to +125 o c sot-23-6 mic5211-1.8/3.3bm6 lfbl mic5211-1.8/3.3ym6 mic5211-blym6 lf bl 1.8v / 3.3v 0 o c to +125 o c sot-23-6 mic5211-2.5/3.3bm6 lfcl mic5211-2.5/3.3ym6 mic5211-clym6 lf cl 2.5v / 3.3v C 40 o c to +125 o c sot-23-6 mic5211-3.3/5.0bm6 lflx mic5211-3.3/5.0ym6 mic5211-lxym6 lf lx 3.3v / 5.0v C 40 o c to +125 o c sot-23-6 other voltages available. contact micrel for details.
may 2006 3 mic5211 mic5211 micrel, inc. absolute maximum ratings (note 1) supply input voltage (v in ) .............................. C20v to +20v enable input voltage (v en ) ............................ C20v to +20v power dissipation (p d ) ............................. internally limited storage temperature range .................... C60c to +150c lead temperature (soldering, 5 sec.) ........................ 260c esd, (note 3) ...................................................................... electrical characteristics v in = v out + 1v; i l = 1ma; c l = 0.1f, and v en 2.0v; t j = 25c, bold values indicate C40c to +125c; for one-half of dual mic5211; unless noted. symbol parameter conditions min typical max units v o output voltage variation from nominal v out C3 3 % accuracy C4 4 % v o /t output voltage note 5 50 200 ppm/c temperature coeffcient v o /v o line regulation v in = v out +1v to 16v 0.008 0.3 % 0.5 % v o /v o load regulation i l = 0.1ma to 50ma, note 6 0.08 0.3 % 0.5 % v in C v o dropout voltage, note 7 i l = 100a 20 mv i l = 20ma 200 450 mv i l = 50ma 250 500 mv i q quiescent current v en 0.4v (shutdown) 0.01 10 a i gnd ground pin current v en 2.0v, i l = 100a (active) 90 a note 8 i l = 20ma (active) 225 450 a i l = 50ma (active) 750 1200 a i limit current limit v out = 0v 140 250 ma v o /p d thermal regulation note 9 0.05 %/w enable input enable input voltage level v il logic low (off) 0.6 v v ih logic high (on) 2.0 v i il enable input current v il 0.6v 0.01 1 a i ih v ih 2.0v 3 50 a note 1: exceeding the absolute maximum rating may damage the device. note 2: the device is not guareented to function outside itsperating rating. note 3: devices are esd sensitive. handling precautions recommended. note 4: the maximum allowable power dissipation at any t a (ambient temperature) is p d(max) = (t j(max) C t a ) / ja . exceeding the maximum allow - able power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. the ja is 220c/w for the sot-23-6 mounted on a printed circuit board. note 5: output voltage temperature coef?ecient is de?ned as the worst case voltage change divided by the total temperature range. note 6: regulation is measured at constant junction temperature using low duty cycle pulse testing. parts are tested for load regulation in the load range from 0.1ma to 50ma. change in output voltage due to heating effects are covered by thermal regulation speci?cation. note 7: dropout voltage is de?ned as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1v differential. for output voltages below 2.5v, dropout voltage is the input-to-output voltage differential with the minimum voltage being 2.5v. minimum input opertating voltage is 2.5v. note 8: ground pin current is the quiescent current per regulator plus pass transistor base current. the total current drawn from the supply is the sum of the load current plus the ground pin current. note 9: thermal regulation is de?ned as the change in output voltage at a time t after a change in power dissipation is applied, excluding load or line regulation effects. speci?cations are for a 50ma load pulse at v in = 16v for t = 10ms. operating ratings (note 2) supply input voltage (v in ) ................................. 2.5v to 16v enable input voltage (v en ) .................................. 0v to 16v junction temperature (t j ) (except 1.8v) .. C40c to +125c 1.8v only ................................................... 0c to +125c 6-lead sot-23-6 ( ja ) ............................................. note 4
mic5211 micrel, inc. mic5211 4 may 2006 typical characteristics
may 2006 5 mic5211 mic5211 micrel, inc.
mic5211 micrel, inc. mic5211 6 may 2006 crosstalk characteristi c i outb = 100a c outb = 0.47f c ou ta = 0.47f time (25ms/div .) i t u o a i d / a m 0 5 ( . v ) v t u o a i d / v m 0 5 ( . v ) v b t u o i d / v m 0 5 ( . v )
may 2006 7 mic5211 mic5211 micrel, inc. applications information enable/shutdown ena and enb (enable/shutdown) may be controlled sepa - rately. forcing ena/b high (>2v) enables the regulator. the enable inputs typically draw only 15a. while the logic threshold is ttl/cmos compatible, ena/b may be forced as high as 20v, independent of v in . ena/b may be connected to the supply if the function is not required. input capacitor a 0.1f capacitor should be placed from in to gnd if there is more than 10 inches of wire between the input and the ac ?lter capacitor or when a battery is used as the input. output capacitor typical pnp based regulators require an output capacitor to prevent oscillation. the mic5211 is ultrastable, requiring only 0.1f of output capacitance per regulator for stability. the regulator is stable with all types of capacitors, includ - ing the tiny, low-esr ceramic chip capacitors. the output capacitor value can be increased without limit to improve transient response. the capacitor should have a resonant frequency above 500khz. ceramic capacitors work, but some dielectrics have poor temperature coef?cients, which will affect the value of the output capacitor over temperature. tantalum capacitors are much more stable over temperature, but typically are larger and more expensive. aluminum electrolytic capacitors will also work, but they have electrolytes that freeze at about C30c. tantalum or ceramic capacitors are recommended for operation below C25c. no-load stability the mic5211 will remain stable and in regulation with no load (other than the internal voltage divider) unlike many other voltage regulators. this is especially important in cmos ram keep-alive applications. thermal shutdown thermal shutdown is independent on both halves of the dual mic5211, however, an overtemperature condition in one half may affect the other half because of proximity. thermal considerations when designing with a dual low-dropout regulator, both sec - tions must be considered for proper operation. the part is designed with thermal shutdown, therefore, the maximum junction temperature must not be exceeded. since the dual regulators share the same substrate, the total power dissipa - tion must be considered to avoid thermal shutdown. simple thermal calculations based on the power dissipation of both regulators will allow the user to determine the conditions for proper operation. the maximum power dissipation for the total regulator system can be determined using the operating temperatures and the thermal resistance of the package. in a minimum footprint con?guration, the sot-23-6 junction-to-ambient thermal resistance ( ja ) is 220c/w. since the maximum junction temperature for this device is 125c, at an operating tem - perature of 25c the maximum power dissipation is: p d(max) = t j(max) C t a ja p d(max) = 125c C 25c 220c/w p d(max) = 455mw the mic5211-3.0 can supply 3v to two different loads indepen - dently from the same supply voltage. if one of the regulators is supplying 50ma at 3v from an input voltage of 4v, the total power dissipation in this portion of the regulator is: p d1 = (v in C v out ) i out + v in ? i gnd p d1 = (4v C 3v) 50m a + 4v ? 0.85m a p d1 = 53.4mw up to approximately 400mw can be dissipated by the remain - ing regulator (455mw C 53.4mw) before reaching the thermal shutdown temperature, allowing up to 50ma of current. p d2 = (v in C v out ) i out + v in ? i gnd p d2 = (4v C 3v) 50m a + 4v ? 0.85m a p d2 = 53.4mw the total power dissipation is: p d1 + p d2 = 53.4mw + 53.4mw p d1 + p d2 = 106.8mw therefore, with a supply voltage of 4v, both outputs can oper - ate safely at room temperature and full load (50ma). mic5211 in outa gnd v in ena o ut b 1f v outa e n b v ou tb 1f figure 1. thermal conditions circuit in many applications, the ambient temperature is much higher. by recalculating the maximum power dissipation at 70c ambient, it can be determined if both outputs can supply full load when powered by a 4v supply. p d(max) = t j(max) C t a ja p d(max) = 125c C 70c 220c/w p d(max) = 250mw at 70c, the device can provide 250mw of power dissipation, suitable for the above application. when using supply voltages higher than 4v, do not exceed the maximum power dissipation for the device. if the device is operating from a 7.2v-nominal two-cell lithium-ion battery and
mic5211 micrel, inc. mic5211 8 may 2006 both regulators are dropping the voltage to 3.0v, then output current will be limited at higher ambient temperatures. for example, at 70c ambient the ?rst regulator can supply 3.0v at 50ma output from a 7.2v supply; however, the sec - ond regulator will have limitations on output current to avoid thermal shutdown. the dissipation of the ?rst regulator is: p d1 = (7.2v C 3v ) 50ma + 7.2v 0.85ma p d1 = 216mw since maximum power dissipation for the dual regulator is 250mw at 70c, the second regulator can only dissipate up to 34mw without going into thermal shutdown. the amount of current the second regulator can supply is: p d2(max) = 34mw (7.2v C 3v) i out2(max) = 34mw 4.2v ? i out2(max) = 34mw i out2(max) = 8ma the second regulator can provide up to 8ma output current, suitable for the keep-alive circuitry often required in hand- held applications. refer to application hint 17 for heat sink requirements when higher power dissipation capability is needed. refer to design - ing with low dropout voltage regulators for a more thorough discussion of regulator thermal characteristics. dual-voltage considerations for con?gurations where two different voltages are needed in the system, the mic5211 has the option of having two independent output voltages from the same input. for ex - ample, a 3.3v rail and a 5.0v rail can be supplied from the mic5211 for systems that require both voltages. important considerations must be taken to ensure proper functionality of the part. the input voltage must be high enough for the 5v section to operate correctly, this will ensure the 3.3v section proper operation as well. both regulators live off of the same input voltage, therefore the amount of output current each regulator supplies may be limited thermally. the maximum power the mic5211 can dissipate at room temperature is 455mw, as shown in the thermal considerations section. if we assume 6v input voltage and 50ma of output current for the 3.3v section of the regulator, then the amount of output current the 5v section can provide can be calculated based on the power dissipation. p d = (v gnd C v out ) i out + v gnd i gnd p d(3.3v) = (6v C 3.3v) 50ma + 6v 0.85ma p d(3.3v) = 140.1mw p d(max) = 455mw p d(max) C p d(3.3v) = p d(5v) p d(5v) = 455mw C 140.1mw p d(5v) = 314.9mw based on the power dissipation allowed for the 5v section, the amount of output current it can source is easily calculated. p d(5v) = 314.9mw 314.9mw = (6v C 5v) i max C 6v i gnd (i gnd typically adds less than 5% to the total power dissipa - tion and in this case can be ignored) 314.9mw = (6v C 5v) i max i max = 314.9ma i max exceeds the maximum current rating of the device. therefore, for this condition, the mic5211 can supply 50ma of output current from each section of the regulator.
may 2006 9 mic5211 mic5211 micrel, inc. package information sot-23-6 (m6) 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 this information furnished by micrel in this data sheet is believed to be accurate and reliable. however no responsibility is assumed by micrel for its use. micrel reserves the right to change circuitry and speci?cations at any time without noti?cation to the customer. micrel products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. life support devices or systems are devices or systems that (a) are intended 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 signi? cant 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. ? 2000 micrel , inc.
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