technical note power management lsi series for automotive body control ldo regulator BD3940FP, bd3941fp/hfp/t z description bd394 fp series regulators feature a high 36 v breakdown voltage and ar e compatible with onboard vehicle microcontrollers. they offer an output current of 500 ma while limiting dark current to 30 a (typ). the series supports the use of ceramic capacitors as output phase compensation capacitors. since the ics us e p-channel dmos output transistors, increas ed loads do not result in increased total supply current. bd394 fp series is ideal for lowering current consumption and costs in battery direct-coupled systems. z features 1) super-low dark current: 30 a (typ.) 2) low-saturation voltage type p-channel dmos output transistors output on resistance: 1.6 ? (typ.) 3) high precision output voltage: 5 v 2% (ta = 25c) / iomax = 500 ma 4) low-esr ceramic capacitors can be used as output capacitors 5) vcc power supply voltage = 36 v / peak power supply voltage = 50 v (tr 1 ms, th 200 ms) 6) built-in over current protection circuit and thermal shutdown circuit 7) to252-3/hrp-5/to220fp-3 package z applications vehicle equipment, car stereos, satellite navigation systems, etc. z product line model BD3940FP bd3941fp/hfp/t output voltage 3.3 v 5.0 v z absolute maximum ratings (ta = 25c) parameter symbol limit unit power supply voltage vcc 36 *1 v output current io 500 ma 1.2 *2 1.6 *3 power dissipation pd 2.0 *4 w operating temperature range topr ? 40 to +125 c storage temperature range tstg ? 55 to +150 c peak power supply voltage vcc peak 50 *5 v maximum junction temperature tjmax 150 c *1 not to exceed pd. *2 for to252-3, reduced by 9.6 mw/c over 25c, when mounted on a glass epoxy board (70 mm 70 mm 1.6 mm). *3 reduced by 12.8 mw/c over 25c, when mounted on a glass epoxy board (70 mm 70 mm 1.6 mm). *4 for to220fp-3, reduced by 16.0 mw/c over 25c. *5 application time 200 ms or shorter. (tr 1 ms) ver.b oct2005 high temperature operating now available
2/8 z recommended operating conditions (ta = 25c) parameter symbol min. max. unit BD3940FP/hfp vcc 4.5 25.0 v input voltage bd3941fp/hfp/t vcc 6.2 25.0 v output current io ? 500 ma z electrical characteristics (unless otherwise specified, ta = 25c; vcc = 13.2 v; io = 200 ma) limit parameter symbol min. typ. max. unit conditions bias current 1 ib1 ? 30 40 a io = 0 ma bias current 2 ib2 ? 30 ? a io = 200 ma BD3940FP vo 3.234 3.300 3.366 v output voltage bd3941fp/hfp/t vo 4.900 5.000 5.100 v output current io 500 ? ? ma BD3940FP vcc = 3.135 v, io = 100 a minimum i/o voltage difference bd3941fp/hfp/t ? vd ? 0.45 0.65 v vcc = 4.75 v, io = 200 a ripple rejection r.r. 45 55 ? db f = 120 hz, ein = 1 vrms, io = 100 ma BD3940FP vcc = 4.5 v 25 v input stability bd3941fp/hfp/t reg.i ? 10 30 mv vcc = 6.2 v 25 v load stability reg.l ? 20 60 mv io = 0 ma 200 ma z electrical characteristics (unless otherwise specified, ta = ? 40c to +125c; vcc = 13.2 v; io = 200 ma) limit parameter symbol min. typ. max. unit conditions bias current 1 ib1 ? 30 40 a io = 0 ma bias current 2 ib2 ? 30 ? a io = 200 ma BD3940FP vo 3.168 3.300 3.366 v output voltage bd3941fp/hfp/t vo 4.800 5.000 5.100 v output current io 500 ? ? ma BD3940FP vcc = 3.135 v, io = 100 a minimum i/o voltage difference bd3941fp/hfp/t ? vd ? ? 0.9 v vcc = 4.75 v, io = 200 a ripple rejection r.r. 45 55 ? db f = 120 hz, ein = 1 vrms, io = 100 ma BD3940FP vcc = 4.5 v 25 v input stability bd3941fp/hfp/t reg. ? 10 45 mv vcc = 6.2 v 25 v load stability reg.l ? 20 60 mv io = 0 ma 200 ma note: this ic is not designed to be radiation-resistant. note: all characteristics are measured with 0.33 f and 0.1 f capacitors connected to input and output pins, respectively. because measurements (pulse measurements) were taken when ta tj, data other than the output voltage/temperature coefficient does not include fluctuations due to temperature variations.
3/8 z reference data (unless otherwise specified, ta = 25c) 0 10 20 30 40 50 0 5 10 15 20 25 supply voltage: v [v] circuit current: icc [a] 0 1 2 3 4 5 6 0 500 1000 1500 2000 output current: io [ma] output voltage: vo [v] 0 1 2 3 4 5 6 0 5 10 15 20 25 supply voltage: v [v] output voltage: vo [v] fig. 1 total supply current fig. 3 output voltage vs load ta = 25c ta = 125c ta = ? 40c fig. 2 output voltage vs power supply voltage ta = 125c ta = 25c ta = ? 40c 0 0.05 0.1 0.15 0.2 0 100 200 300 400 500 output current: io [ma] circuit current: icc [ma] 0 1 2 3 4 5 6 100 120 140 160 180 200 ambient temperature: ta [ ] output voltage: vo [v] 4.5 4.75 5 5.25 5.5 -40 0 40 80 120 ambient temperature: ta [ ] output voltage: vo [v] fig. 9 output voltage vs te m p erature fig. 8 thermal shutdown circuit fig. 7 total supply current classified by load 0 0.2 0.4 0.6 0.8 1 0 100 200 300 400 500 output current: io [ma] dropout voltage: ? vd [v] 0 10 20 30 40 50 60 70 10 100 1000 10000 100000 1e+06 frequency: f [hz] ripple rejection: r.r. [db] 0 1 2 3 4 5 6 20 25 30 35 40 supply voltage: vcc [v] output voltage: vo [v] fig. 5 ripple rejection fig. 4 i/o voltage difference fig. 6 overvoltage protection ta = 25c ta = ? 40c ta = 125c fig. 10 ripple rejection vs temperature 45 50 55 60 65 -40 0 40 80 120 ambient temperature: ta [ ] ripple rejection: r.r. [db] fig. 11 min. i/o voltage differential vs temperature fig. 12 total supply current vs temperature 0 0.1 0.2 0.3 0.4 0.5 0.6 -40 0 40 80 120 ambient temperature: ta [ ] dropout voltage: ? vd [v] 0 10 20 30 40 50 -40 0 40 80 120 ambient temperature: ta [ ] circuit current: icc [a]
4/8 z block diagram fig.13 to252-3 fig.14 hrp5 fig.15 to220fp-3 cin : 0.33 f to 1000 f co : 0.1 f to 1000 f z pin assignments ? to252-3 fig.16 ? hrp5 fig.17 ? to220fp-3 fig.18 pin no. pin no. function 1 vcc power supply pin 2 n.c. nc pin 3 vo voltage output pin fin gnd ground pin pin no. pin no. function 1 vcc power supply pin 2 n.c. nc pin 3 gnd ground pin 4 n.c. nc pin 5 vo voltage output pin fin gnd ground pin pin no. pin no. function 1 vcc power supply pin 2 gnd ground pin 3 vo voltage output pin 1 2 3 fin 1 2 3 4 5 fin 12 3 co gnd vcc vref ocp ovp tsd vo fin 1 n.c . 2 5 cin n.c 4 3 gnd vcc vref ocp ovp tsd vo 1 3 cin co co 2 gnd vcc vref ocp ovp tsd vo fin 1 n.c 2 cin 3
5/8 z thermal design to252-3 hrp5 to220fp-3 fig.19 fig.20 fig.21 refer to the dissipation reduction illustrated in figs. 19 to 21 when using the ic in an environment where ta 25c. the characteristics of the ic are greatly influenced by the operating temperature. if the temper ature exceeds the maximum juncti on temperature tjmax, the ele ments of the ic may be damaged. it is necessary to give sufficient consideration to the heat of the ic in view of two points, i.e., the protect ion of the ic from instantaneous damage and the maintenance of the reliability of the ic in long-time operation. in order to protect the ic from thermal destruction, the operati ng temperature of the ic must not exceed the maximum junction t emperature tjmax. fig. 19 illustrates the power dissipation/power reduction for t he to252 package. operate the ic within the power dissipation pd . the following method is used to calculate t he power consumption pc (w). pc = (vcc ? vo) io + vcc icc vcc: input voltage power dissipation pd pc vo: output voltage io: load current icc: total supply current the load current io is obtained to operate the ic within the power dissipation. (refer to icc in fig.12) the maximum load current iomax for the applied voltage v cc can be calculated during the thermal design process. calculation example example) vcc = 12 v and vo = 5.0 v at ta = 85c, bd3941fp io 89 ma (icc = 30 a) make a thermal calculation in consideration of the above equatio ns so that the whole operating temperature range will be within the power dissipation. the power consumption pc of t he ic, in the event of shorting (i.e., if the vo and gnd pins are shorted), will be o btained from the following equation: pc = vcc (icc + ishort) ishort: short current z external settings for pins and precautions 1) vcc pin insert capacitors with a capacitance of 0.33 f to 1,000 f between the vcc and gnd pins. the capacitance varies with the application. be sure to design the capacitance with a sufficient margin. 2) capacitors for stopping oscillation at output pins capacitors for stopping oscillation must be placed between each ou tput pin and the gnd pin. use a capacitor within a capacitanc e range between 1 f and 1,000 f. a ceramic capacitor with low esr values, from 0.001 ? to 100, can be used. unstable input voltage and load fluctuations can affect output voltages. output capacitor ca pacitance values should be deter mined for actual application. io pd ? vcc icc vcc ? vo io 0.624 ? 12 icc 12 ? 5 ja = 104.2c/w ? 9.6 maw/c 25c = 1.2 w 85c = 0.624 w 1.2w 1.6w a mbient temperature: ta [ ] power dissipation: pd [w] a mbient temperature: ta [ ] power dissipation: pd [w] (1)20w (2)2.0w a mbient temperature: ta [ ] power dissipation: pd [w] 0.4 0 0.8 1.2 1.6 2.0 0 25 50 75 100 125 150 0.4 0 0.8 1.2 1.6 2.0 0 25 50 75 100 125 150 0 10 15 20 25 5 0 25 50 75 100 125 150 ic mounted on a rohm standard board board size: 70 mm 70 mm 1.6mm ja = 104.2 (c /w) ic mounted on a rohm standard board board size: 70 mm 70 mm 1.6mm ja = 78.1 (c /w) (1) o????r ja=6.25( /w) (2)ic gr ja=62.5( /w)
6/8 z operation notes 1) absolute maximum ratings an excess in the absolute maximum ratings, such as supply volt age, temperature range of operati ng conditions, etc., can break d own the devices, thus making impossible to identify breaking mode, such as a short circuit or an open circuit. if any over rated values will expect to exceed the absolute maximum ra tings, consider adding ci rcuit protection devices , such as fuses. 2) gnd voltage the potential of gnd pin must be minimum potential in all operating conditions. 3) thermal design use a thermal design that allows for a sufficient margin in li ght of the power dissipation (pd) in actual operating conditions. 4) inter-pin shorts and mounting errors use caution when positioning the ic for m ounting on printed circuit boards. the ic ma y be damaged if there is any connection er ror or if pins are shorted together. 5) actions in str ong electromagnetic field use caution when using the ic in the pr esence of a strong electromagnetic field as doing so may cause the ic to malfunction. 6) testing on application boards when testing the ic on an application board, connecting a capacitor to a pin with low impedance subjects the ic to stress. alwa ys discharge capacitors after each process or st ep. always turn the ic's power supply off before connecting it to or removing it f rom a jig or fixture during the inspection process. ground the ic during assembly steps as an antista tic measure. use si milar precaution whe n transporting or storing the ic. 7) regarding input pin of the ic this monolithic ic contains p+ isolati on and p substrate layers between adjacent el ements in order to keep them isolated. p-n junctions are formed at the intersecti on of these p layers with the n layers of other elements, creating a parasitic diode or transistor. for example, the relation between each potential is as follows: when gnd > pin a and gnd > pin b, the p-n junction operates as a parasitic diode. when gnd > pin b, the p-n junction oper ates as a parasitic transistor. parasitic diodes can occur inevitable in the structure of the ic . the operation of parasitic diodes can result in mutual interf erence among circuits, operational faults, or physical damage. accordingly, methods by which parasitic diodes operate, such as applying a vo ltage that is lower than the gnd (p substrate) vo ltage to an input pin, should not be used. fig.22 example of a simple monolithic ic architecture 8) ground wiring pattern when using both small signal and large current gnd patterns, it is recommended to isolate the two ground patterns, placing a si ngle ground point at the ground potential of application so that the pattern wiring resistance and volt age variations caused by larg e currents do not cause variations in the small signal ground voltage. be care ful not to change the gnd wiring pattern of any external compon ents, either. parasitic elements (pina) parasitic elements or transistors (pinb) gnd c b e gnd n p n n p+ p+ parasitic elements or transistors p substrate (pinb) c b e transistor (npn) (pina) gnd n p n n p+ p+ resistor parasitic elements p
7/8 9) applications or inspection processe s with modes where the potentials of the vcc pin and other pins may be reversed from th eir normal states may cause damage to the ic's internal circuitry or elements. use an output pin capacitance of 1,000 f or lower in case vcc is shorted with the gnd pin while the external capacitor is charged. it is recommended to insert a diode for preventing back current flow in series with vcc or bypass diodes between vcc and each pin. fig. 23 10) thermal shutdown circuit (tsd) this ic incorporates a built-in thermal shutdown circuit for the protection from thermal destr uction. the ic should be used wit hin the specified power dissipation range. however, in the event that t he ic continues to be operated in excess of its power dissipatio n limits, the attendant rise in the chip?s temperature tj will trigger the ther mal shutdown circuit to turn off all output power elements. th e circuit will automatically reset once the chip?s temperature tj drops. operatio n of the thermal shutdown circuit presumes that the ic?s abso lute maximum ratings have been exceeded. applicati on designs should never make use of the thermal shutdown circuit. (see fig.8) 11) overcurrent prot ection circuit (ocp) the ic incorporates a built-in overcurrent protection circuit that operates according to the output current capacity. this circ uit serves to protect the ic from damage when the load is shorted. the protecti on circuit is designed to limit current flow by not latching i n the event of a large and instantaneous current flow originating from a large capacitor or other component. however, while this protection ci rcuit is effective in preventing damage due to sudden and unexpected accidents, it is not compatible with continuous operation or use du ring transitional periods. at the time of ther mal designing, keep in mind that the current capability has negative characteristics t o temperatures. (see fig. 3.) 12) overvoltage protection circuit (ovp) overvoltage protection is designed to turn off all output when the voltage differential between the vcc and gnd pins exceeds approximately 30 v (typ.). use caution when determining t he power supply voltage range to use. (see fig. 6) z selecting a model name when ordering rohm model name part number 3940: 3.3 v output 3941: 5.0 v output packaging type fp : to252-3 hfp : hrp5 t : to220fp-3 taping e2 : reel-wound embossed taping b d 1 9 3 4 p f e 2 embossed carrier tape e2 (the direction is the 1pin of product is at the lower left when you hold reel on the left hand and you pull out the tape on the right hand) tape quantity direction of feed 2000 p cs reel 1pin x x x x x x x x x x x x x x x x x x x x x x x x to252-3 (unit:mm) 6.5 0.2 c0.5 2 13 0.8 0.65 0.65 2.3 0.2 2.3 0.2 0.5 0.1 1.5 2.5 9.5 0.5 2.3 0.2 0.5 0.1 5.1 + 0.2 ? 0.1 5.5 0.2 1.5 0.2 0.75 1.0 0.2 fin when you order , please order in times the amount of package quantity. direction of feed vcc bypass diode diode for preventing back current flow pin
8/8 catalog no.05t389be '05.10 rohm c 1000 tsu the contents described herein are correct as of october, 2005 the contents described herein are subject to change without notice. for updates of the latest information, please contact and confirm with rohm co.,ltd. any part of this application note must not be duplicated or copied without our permission. application circuit diagrams and circuit constants contained herein are shown as examples of standard use and operation. p lease pay careful attention to the peripheral conditions when designing circuits and deciding upon circuit constants in the set. any data, including, but not limited to application circuit diagrams and information, described herein are intended only a s illustrations of such devices and not as the specifications for such devices. rohm co.,ltd. disclaims any warranty that any use of such devices shall be free from infringement of any third party's intellectual property rights or other proprietary rights, and further, assumes no liability of whatsoever nature in the event of any such infringement, or arising from or connected with or related to the use of such devices. upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or otherwise dispose o f the same, implied right or license to practice or commercially exploit any intellectual property rights or other proprietary rights owned or controlled by rohm co., ltd. is granted to any such buyer. the products described herein utilize silicon as the main material. the products described herein are not designed to be x ray proof. published by application engineering group when you order , please order in times the amount of package quantity. container quantity direction of feed tube 500 p cs direction of products is fixed in a container tube. to220fp-3 (unit:mm) + 0.4 3.2 0.1 0.55 17.0 12.0 0.2 8.0 0.2 1 2.54 0.5 13.5min. 5.0 0.2 0.8 3 2.54 0.5 1.3 ? 0.1 + 0.3 10.0 7.0 1.8 0.2 ? 0.2 ? 0.1 + 0.3 2.6 0.5 ? 0.05 + 0.1 + 0.2 ? 0.1 ? 0.1 + 0.3 4.5 2.8 (unit:mm) hrp5 s s (max 9.745 include burr) 5 4 3 2 1 1.905 0.1 0.835 0.2 1.523 0.15 10.54 0.13 - 0.05 + 0.1 0.27 4.5 (5.59) 8.82 ? 0.1 9.395 0.125 0.08 0.73 0.1 1.72 0.08 0.05 (7.49) 8.0 ? 0.13 1.017 0.2 1.2575 - 4.5 + 5.5 embossed carrier tape tr (the direction is the 1pin of product is at the upper light when you hold reel on the left hand and you pull out the tape on the right hand) tape quantity direction of feed 2000 p cs when you order , please order in times the amount of package quantity. reel 1pin direction of feed x x x x x x x x x x x x x x x x x x x x
notes no technical content pages of this document may be reproduced in any form or transmitted by any means without prior permission of rohm co.,ltd. the contents described herein are subject to change without notice. the specifications for the product described in this document are for reference only. upon actual use, therefore, please request that specifications to be separately delivered. application circuit diagrams and circuit constants contained herein are shown as examples of standard use and operation. please pay careful attention to the peripheral conditions when designing circuits and deciding upon circuit constants in the set. any data, including, but not limited to application circuit diagrams information, described herein are intended only as illustrations of such devices and not as the specifications for such devices. rohm co.,ltd. disclaims any warranty that any use of such devices shall be free from infringement of any third party's intellectual property rights or other proprietary rights, and further, assumes no liability of whatsoever nature in the event of any such infringement, or arising from or connected with or related to the use of such devices. upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or otherwise dispose of the same, no express or implied right or license to practice or commercially exploit any intellectual property rights or other proprietary rights owned or controlled by rohm co., ltd. is granted to any such buyer. products listed in this document are no antiradiation design. appendix1-rev2.0 thank you for your accessing to rohm product informations. more detail product informations and catalogs are available, please contact your nearest sales office. rohm customer support system the americas / europe / asia / japan contact us : webmaster@ rohm.co. jp www.rohm.com copyright ? 2008 rohm co.,ltd. the products listed in this document are designed to be used with ordinary electronic equipment or de vices (such as audio visual equipment, office-automation equipment, communications devices, electrical appliances and electronic toys). should you intend to use these products with equipment or devices which require an extremely high level of reliability and the malfunction of which would directly endanger human life (such as medical instruments, transportation equipment, aerospace machinery, nuclear-reactor controllers, fuel controllers and other safety devices), please be sure to consult with our sales representative in advance. it is our top priority to supply products with the utmost quality and reliability. however, there is always a chance of failure due to unexpected factors. therefore, please take into account the derating characteristics and allow for sufficient safety features, such as extra margin, anti-flammability, and fail-safe measures when designing in order to prevent possible accidents that may result in bodily harm or fire caused by component failure. rohm cannot be held responsible for any damages arising from the use of the products under conditions out of the range of the specifications or due to non-compliance with the notes specified in this catalog. 21 saiin mizosaki- cho, ukyo-ku, kyoto 615-8585, japan tel : +81-75-311-2121 fax : +81-75-315-0172 appendix
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