3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 1/9 htc sop8-pp to-252 3l / 5l pkg to-263 3l / 5l pkg ordering information device package tj4230gdp-adj tj4230gdp-x.x sop8-pp tj4230grs-adj tj4230grs-x.x to-252 3l/5l tj4230gr-adj tj4230gr-x.x to-263 3l/5l features ? ultra low dropout voltage ? compatible with low esr ml cc as input/output capacitor ? good line and load regulation ? guaranteed output current of 3a ? available in sop8-pp, to-252 and to-263 packages ? fixed output voltages : 1.0v, 1.2v, 1.8v, 2.5v, and 3.3v ? sense option improves load regulation ? over-temperature/over-current protection ? -40 oc to 125 oc junction temperature range application ? lcd tvs and settop boxes ? battery powered equipments ? motherboards and graphic cards ? microprocessor power supplies ? peripheral cards ? high efficiency linear regulators ? battery chargers description the tj4230 series of high performance ultra-low dropout linear regulators operates from 2.5v to 6v input supply and provides ultra-low dropout volt age, high output current with low ground current. wide range of preset output voltage options are available. these ultra-low dropout linear regulators respond fast to step changes in load which makes them suitable for low voltage micro-processor applications. the tj4230 is developed on a cmos process technology which allows low quiescent current operation independent of output load current. this cmos process also allows the tj4230 to operate under extremely low dropout conditions. x.x = output voltage = 1.0, 1.2, 1.8, 2.5, and 3.3 absolute maximum ratings characteristic symbol min. max. unit input supply voltage (survival) v in - 6.5 v enable input voltage (survival) v en - 6.5 v maximum output current i max - 3 a lead temperature (soldering, 5 sec) t sol 260 oc storage temperature range t stg -65 150 oc operating junction temperature range t jopr -40 125 oc package thermal resistance * ja-sop8-pp 68 oc/w * calculated from package in still air, mounted to 2.6mm x 3.5mm(mi nimum foot print) 2 layer pcb without thermal vias per jesd5 1 standards.
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 2/9 htc ordering information v out package order no. description package marking status sop8-pp tj4230gdp-adj 3a, adjustable, enable tj4230g-adj contact us to-252 5l tj4230grs-adj-5l 3a, adjustable, enable tj4230g-adj contact us adj to-263 5l tj4230gr-adj-5l 3a, adjustable, enable tj4230g-adj contact us sop8-pp tj4230gdp-1.0v 3a, enable, sense tj4230g-1.0 contact us to-252 3l tj4230grs-1.0v-3l 3a tj4230g-1.0 contact us to-252 5l tj4230grs-1.0v-5l 3a, enable, sense tj4230g-1.0 contact us to-263 3l tj4230gr-1.0v-3l 3a tj4230g-1.0 contact us 1.0v to-263 5l tj4230gr-1.0v-5l 3a, enabl e, sense tj4230g-1.0 contact us sop8-pp tj4230gdp-1.2 3a, enable, sense tj4230g-1.2 contact us to-252 3l tj4230grs-1.2v-3l 3a tj4230g-1.2 contact us to-252 5l tj4230grs-1.2v-5l 3a, enable, sense tj4230g-1.2 contact us to-263 3l tj4230gr-1.2v-3l 3a tj4230g-1.2 contact us 1.2v to-263 5l tj4230gr-1.2v-5l 3a, enable, sense tj4230g-1.2 contact us sop8-pp tj4230gdp-1.8v 3a, enable, sense tj4230g-1.8 contact us to-252 3l tj4230grs-1.8v-3l 3a tj4230g-1.8 contact us to-252 5l tj4230grs-1.8v-5l 3a, enable, sense tj4230g-1.8 contact us to-263 3l tj4230gr-1.8v-3l 3a tj4230g-1.8 contact us 1.8v to-263 5l tj4230gr-1.8v-5l 3a, enabl e, sense tj4230g-1.8 contact us sop8-pp tj4230gdp-2.5v 3a, enable, sense tj4230g-2.5 contact us to-252 3l tj4230grs-2.5v-3l 3a tj4230g-2.5 contact us to-252 5l tj4230grs-2.5v-5l 3a, enable, sense tj4230g-2.5 contact us to-263 3l tj4230gr-2.5v-3l 3a tj4230g-2.5 contact us 2.5v to-263 5l tj4230gr-2.5v-5l 3a, enable, sense tj4230g-2.5 contact us sop8-pp tj4230gdp-3.3v 3a, enable, sense tj4230g-3.3 contact us to-252 3l tj4230grs-3.3v-3l 3a tj4230g-3.3 contact us to-252 5l tj4230grs-3.3v-5l 3a, enable, sense tj4230g-3.3 contact us to-263 3l tj4230gr-3.3v-3l 3a tj4230g-3.3 contact us 3.3v to-263 5l tj4230gr-3.3v-5l 3a, enabl e, sense tj4230g-3.3 contact us lead count : 3l / 5l (applied for to252 and to263 only) output voltage : adj / 1.0v / 1.2v / 1.8v / 2.5v / 3.3v package type dp rs r : sop8-pp : to252 : to263 root name product code t j 4 2 3 0 g r s ? a d j ? 5 l material class g blank : halogen free : pb free
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 3/9 htc pin configuration exposed pad n.c en vin n.c gnd adj / sense vout n.c 1 2 3 4 8 7 6 5 sop8-pp to252-3l to252-5l to263-3l to263-5l pin description to252/to263 3 lead to252/to263 5 lead sop8-pp pin no. name function name function name function 1 v in input supply en chip enable - n.c. 2 gnd ground v in input supply en chip enable 3 v out output voltage gnd ground v in input supply 4 - - v out output voltage - n.c. 5 - - sense/adj remote sense or output adjust - n.c. 6 - - - - v out output voltage 7 - - - - sense/adj remote sense or output adjust 8 - - - - gnd ground * exposed pad of sop8-pp package should be externally connected to gnd.
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 4/9 htc basic application typical 3 pin application c out 10uf c in 10uf v in v out tj4230 gnd vin vout typical 5 / 8 pin application c out 10uf c in 10uf en v in v out sense tj4230 gnd vin vout en 5 / 8 pin remote load sense application c in 10uf en v in v out sense tj4230 gnd vin en c out 10uf l o a d vout typical adjustable version application c out 10uf c in 10uf en v in v out adj tj4230 gnd vin vout en r2 r1 c ff * tj4230 can deliver a continuous current of 3a over the full operating temperat ure. however, the output current is limited by the restriction of power dissipation which diff ers from packages. a heat sink may be required depending on the maximum power dissipation and maximum ambient temper ature of application. with respect to the applied package, the maximum output current of 3a may be still undeliverable. * see application information.
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 5/9 htc electrical characteristics (note 1) limits in standard typeface are for tj=25oc, and limits in boldface type apply over the full operating temperature range . unless otherwise specified: v in (note 2) = v o(nom) + 1 v, i l = 10 ma, c in = 10 uf, c out = 10 uf, v en = v in - 0.3 v parameter symbol test condit ion min. typ. max. unit output voltage tolerance v o v out +1 v < v in < 5.5 v -2 -3 0 2 3 % adjustable pin voltage (adj version) v adj 2.5 v < v in < 5.5 v 0.784 0.776 0.8 0.816 0.824 v line regulation (note 3) v line v out +1 v < v in < 5.5 v - 0.15 - 0.40 %/v load regulation (note 3, 4) v load 10 ma < i l < 3 a - 0.20 0.50 0.60 % i l = 300 ma - 45 55 65 dropout voltage (note 5) v drop i l = 3 a - 400 500 600 mv i l = 300 ma - 0.40 0.6 1.0 ground pin current (note 6) i gnd i l = 3 a - 0.40 0.6 1.0 ma ground pin current (note 7) i gnd_off v en < 0.2 v - 0.5 1 2 ua f = 1khz - 55 - power supply rejection ratio psrr f = 1khz, c ff = 1uf - 65 - db thermal shutdown temperature t sd - - 165 - oc logic low v il output = low - - 0.4 v enable threshold logic high v ih output = high 2.0 - - v enable input current i en v en = v in - 0.1 - 1 ua note 1. stresses listed as the absolute maximum ratings may c ause permanent damage to the device. these are for stress ratings. functional operating of the device at these or any other conditions beyond th ose indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rati ng conditions for extended periods may rema in possibly to affect device reliability. note 2. the minimum operating value for input voltage is equal to either (v out,nom + v drop ) or 2.5v, whichever is greater. note 3. output voltage line regulation is defined as the change in output voltage from the nominal value due to change in the i nput line voltage. output voltage load regulation is defined as the change in output voltage from the nominal value due to change in load current. note 4. regulation is measured at const ant junction temperature by using a 10ms curr ent pulse. devices are tested for load regu lation in the load range from 10ma to 3a. note 5. dropout voltage is defined as the minimum input to output differential voltage at which the output drops 2% below the n ominal value. dropout voltage specification applies only to output voltages of 2.5v and above. for output voltages below 2.5v, the dropout vo ltage is nothing but the input to output differential, since the minimum input voltage is 2.5v note 6. ground current, or quiescent current, is the di fference between input and output currents. it's defined by i gnd1 = i in - i out under the given loading condition. the total current dr awn from the supply is the sum of the load current plus the ground pin current. note 7. ground current, or standby current, is the input current drawn by a regulator when the output voltage is disabled by an enable signal.
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 6/9 htc application information introduction tj4230 is intended for applications where high current capability and very low dropout voltage are required. it provides a simple, low cost solution that occupies very little pcb estate. additional features include an enable pin to allow for a very low power consumption standby mode, an adjustable pin to provide a fully adjustable output voltage, and sense pin to provide bette r remote load regulation characteristics. component selection input capacitor : a large bulk capacitance over than 10uf should be clos ely placed to the input supply pin of the tj4230 to ensure that the input supply volt age does not sag. also a minimum of 10uf ceramic capacitor is recommended to be placed directly next to the v in pin. it allows for the device being some distance from any bulk capacitor on the rail. additionally, input droop due to lo ad transients is reduced, improving load transient response. additional capacitance may be added if required by the application.(see fig.1) output capacitor : a minimum ceramic capacitor over than 10uf should be ve ry closely placed to the output voltage pin of the tj4230. increasing capacitance will improve t he overall transient response and stability. decoupling (bypass) capacitor : in very electrically noisy environments, it is reco mmended that additional ceramic capacitors be placed from vin to gnd. the use of multiple lower value ceramic capaci tors in parallel with output capacitor also allows to achieve better transient performance and stabilit y if required by the application.(see fig.1) feed-forward capacitor to get the higher psrr than the inher ent performance of tj4230, it is recommended that additional ceramic feed-forward capacitor be placed from vout pin to adj pin. the capacitance of feed-forward capacitor with range of 10pf to 1uf allows to achieve better psrr performance when required by the application.(see fig.2) fig. 1. application with decoupling capacitor, fig. 2. application with feed-forward capacitor, cc1 & cc2 cff delayed start-up when power sequence control is required or rising time of input supply voltage is over than 100usec, it is recommended to apply delayed start-up by using cdelay as shown in fig. 3. it can adjust proper delay by rp-cdelay time constant. and also it can prevent any unexpected transient characteristics at output voltage when the rising time of input supply voltage is as long as 100usec or longer. fig. 3. application with delayed start-up c out 10uf en v in v out sense tj4230 gnd vin vout r p cc2 c in 10uf cc1 c out 10uf c in 10uf en v in v out adj tj4230 gnd vin vout r2 r1 r p cc2 cff cc1 c out 10uf c in 10uf en v in v out adj tj4230 gnd vin vout r2 r1 r p cff c delay
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 7/9 htc output adjustment (adjustable version) an adjustable output device has output voltage range of 0.8v to 5.0v. the operating condition of v in and the operating characteristics of v out depend on the dropout voltage performance in accordance with output load current presented at fig. 7. to obtain a desired output voltage, the following equation can be used with r1 resistor range of 100 ? to 50k ? . c out 10uf c in 10uf en v in v out adj tj4230 gnd vin vout en r2 r1 cff ? ? ? ? ? ? ? = 1 8 0 1 2 . v r r out fig. 4. application for adjustable output voltage to enhance output stability, a feed-forward capacitor of 10nf to 1uf can be placed in series with v out and adj.(refer to "component selection" section) sense pin in applications where the regulator output is not very close to the load, the tj4230 can provide better remote load regulation characteristics using the sense pin. tj4230 regulates the voltage at the output pin. hence, the voltage at the remote load will be lower than the voltage at the output pin as a value of the voltage drop across the trace series resistance. if the sense option pin is not required, the sense pin must be connected to the v out pin. connecting the sense pin to the remote load will provide regulation at the remote load because the tj 4230 regulates the voltage at the sense pin when the sense option pin is used. fig. 5. conventional linear regulator applicatio n fig.6. remote load sense application maximum output current capability the tj4230 can deliver a continuous current of 3a over the full operating ju nction temperature range. however, the output current is limited by the restriction of power dissipat ion which differs from packages. a heat sink may be required depending on the maximum power dissipation and maximum ambient temperature of application. with respect to the applied package, the maximum output current of 3a may be still undeliverable due to the rest riction of the power dissipation of tj4230. under all possible conditions, the junction temperature must be within the range specified under operating conditions. the temperatures over the device are given by: t c = t a + p d x ca t j = t c + p d x jc t j = t a + p d x ja
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 8/9 htc where t j is the junction temperature, t c is the case temperature, t a is the ambient temperature, p d is the total power dissipation of the device, ca is the thermal resistance of case-to-ambient, jc is the thermal resistance of junction-to-case, and ja is the thermal resistance of junction to ambient. the total power dissipation of the device is given by: p d = p in ? p out = (v in x i in )?(v out x i out ) = (v in x (i out +i gnd )) ? (v out x i out ) = (v in - v out ) x i out + v in x i gnd where i gnd is the operating ground current of the device which is specified at the electrical characteristics. the maximum allowable temperature rise (t rmax ) depends on the maximum ambient temperature (t amax ) of the application, and the maximum allowable junction temperature (t jmax ): t rmax = t jmax ? t amax the maximum allowable value for junction-to-ambient thermal resistance, ja , can be calculated using the formula: ja = t rmax / p d tj4230 is available in sop8-pp, to252 and to263 packages. the thermal resistance depends on amount of copper area or heat sink, and on air flow. if proper cooling solution such as heat sink, copper plane area, or air flow is applied, the maximum allowable power dissipation could be increased. howe ver, if the ambient temperature is increased, the allowable power dissipation would be decreased. the graph above is valid for the thermal impedance sp ecified in the absolute maximum ratings section on page 1.
3a ultra low dropout linear regulator tj4230 apr. 2011 ? rev. 1. 0 9/9 htc the ja could be decreased with respect to the copper plane area. so, the specification of maximum power dissipation for an application is fixed, the proper plane area could be estimated by following graphs. wider copper plane area leads lower ja . the maximum allowable power dissipation is also in fluenced by the ambient temperature. with the ja - copper plane area relationship, the maximum allo wable power dissipation could be evaluated with respect to the ambient temperature. as show n in graph, the higher copper plane area leads ja . and the higher ambient temperature leads lower maximum allowable power dissipation.
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