datel, inc., mans eld, ma 02048 (usa) ? tel: (508)339-3000, (800)233-2765 fax: (508)339-6356 ? e?ail: sales@datel.com ? internet: www.datel.com 78sr series 3.3v/5v/12v outputs high-ef ciency switching regulators with lm78xx pinouts features ? 3.3v/0.5a, 5v/0.5a or 12v/0.4a outputs; pin and size-compatible with lm7805 & lm7812 regulators ? up to 95% ef ciency no heat sinks or thermal derating required! ? two sip-packages t existing to-220 footprints: vertical-pin models occupy less than 0.1 square in. optional horizontal pins provide 0.350 in. installed height ? +7.5-36vdc operating input range; low 3ma quiescent current ? built-in lter capacitors no external components required ? ?0 to +70? operation at full load; short-circuit protection ? excellent load (?.2%) and line (?.3%) regulation ? ideal for powering instrumentation from 9v/12v/24v/28v supplies or batteries ? can be used with unregulated dc supplies datel s 7805SR (5v output), 7812sr (12v output) and 7803sr (3.3v output) step-down switching regulators are modern drop-in replacements for older, inef cient, lm7805 and lm7812 linear regulators. the 78xxsr's are pin- and size- compatible with industry-standard to-220 sip packages. a 260khz switching frequency provides for ef ciencies as high as 95%. full-load (up to 0.5a) operation from 9v, 12v, 24v, or 36v supplies at ambient temperatures up to +70? requires no heat sinks, no temperature derating, no forced-air cooling, and no external capacitors. 78sr switching regulators provide many signi cant improvements over their linear counterparts: lower quiescent current (3ma vs. 5 ma), higher input voltage (40v vs. 32v), and better output accuracy (?.5% vs. ?%). all these features combine to make 78sr regulators ideal for new or existing lm7805 & lm7812 applications requiring full-load operation at elevated voltages. technical notes 1. input/output (i/o) filtering: as shown in the noise and ripple graphs, 78sr switching regulators exhibit excellent low-noise performance with no external i/o capacitors. however, if additional noise reduction is required, be sure to use low-esr capacitors that are rated for continu- ous operation (with an additional 20% safety margin) at the highest system voltages and temperatures. adding external output capacitors will also improve the unit s load-transient response. 2. input fusing: 78sr switching regulators are not internally fused. if fusing their input and/or output terminals is required, use the data shown in the ef ciency curves as a guide to selecting an appropriate slow-blow fuse. 3. input-output isolation: 78sr regulators?internal input and output circuits share a common connection (gnd, pin 2); there is no electrical isolation between the input (pin 1) and output (pin 3) terminals. 4. overvoltage protection: 78sr switching regulators do not provide input or output overvoltage protection. in the extremely rare situation in which a catastrophic failure occurs, the output voltage may rise to excessively high levels. if your load must be protected against all possible overvoltage situations, external voltage-limiting circuitry must be provided. 5. operation at 40vdc: operating with inputs up to 40vdc is permissible if, for inputs between 36 and 40vdc, the maximum load current is reduced to 0.35a for 7805SR and 7803sr, and to 0.3a for 7812sr. under no circumstances should the input voltage be allowed to exceed 45vdc. 6. soldering & handling precautions: all units are designed to be hand soldered to pc-boards using no-clean solders (+260?, 5 sec- onds max.). water-soluble solders can also be used, but the units must be washed and dried using processes appropriate to the type of solder employed. see the mechanical speci cations section for pin 1 orientation and recommended plated-through hole dimensions. while 78sr regulators easily withstand a 2kv esd discharge to any terminal (using human body model), they should always be treated as esd sensitive devices. 7. horizontal-pin models (78xxsrh): 78xxsrh switching regulators are pin-compatible replacements for to-220 style lm78xx linear reg- ulators that are installed with their metal tabs lying at on the surface of the pc-board. however, because the surface of inductor l1 on 78xxsrh models is electrically conductive, it must not be allowed to come in contact with any exposed pc-board traces, other than power ground (gnd). while the 2-mil-thick (0.05mm) polyester label attached to l1 provides some degree of electrical insulation (only if l1 sits perfectly at on the pc-board), it is recommended that a 0.020?(0.5mm) clearance be maintained between l1 and all exposed pc-board traces. order online at www.datel.com ? ? a subsidiary of c&d technologies new low-pro le package
high-efficiency switching regulators 78sr series 2 datel, inc., mans? eld, ma 02048 (usa) ? tel: (508)339-3000, (800)233-2765 fax: (508)339-6356 ? e?mail: sales@datel.com ? internet: www.datel.com 7805SR vin = 12v, i load = 50ma typical performance curves t a = +25?, v in as indicated noise and ripple - 10% and 100% load, 20mhz bandwidth 7805SR vin = 12v, i load = 500ma 7812sr vin = 24v, i load = 40ma 7812sr vin = 24v, i load = 400ma performance/functional speci cations typical at t a = +25? input/output models 7803sr 7805SR 7812sr output voltage +3.3vdc +5.0vdc +12.0vdc rated output current 0.5a 0.5a 0.4a output voltage accuracy ?% ?.5% ?% input voltage range ? +7.5-36vdc +7.5-36vdc +15-36vdc line regulation (100% load) ?.3% ?.3% ?.3% load regulation (0-100% load) ?.2% ?.2% ?.2% quiescent current 3ma typ., 5ma max. input current see performance curves ef ciency see performance curves transient response see performance curves input & output noise see performance curves short circuit protection ? continuous isolation none overvoltage protection none undervoltage protection none ? see technical note 5. ? while these regulators can withstand a continuous short-circuit across their output terminals, they will experience a signi cant temperature rise. extended short-circuit operation will adversely affect the unit s reliability. environmental models 7803sr 7805SR 7812sr operating temperature ?0 to +70? storage temperature ?0 to +85? cooling free air convection humidity (non-condensing) 0 to 85% physical mechanical see mechanical speci cations package open-frame sip pins 0.025?(0.64mm) square, tin-plated bronze weight 0.08 ounces (2.2g) pin soldering +260? for 5 seconds 7803sr vin = 12v, i load = 50ma 7803sr vin = 12v, i load = 500ma
high-efficiency switching regulators 78sr series 3 datel, inc., mans? eld, ma 02048 (usa) ? tel: (508)339-3000, (800)233-2765 fax: (508)339-6356 ? e?mail: sales@datel.com ? internet: www.datel.com transient response - 90% load step 7812sr 100% to 10% load step 7805SR 10% to 100% load step 7805SR 100% to 10% load step 7812sr 10% to 100% load step 7805SR ef ciency 7803sr 10% to 100% load step 7803sr 100% to 10% load step 0 50 100 150 200 250 300 350 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 input voltage (volts dc) 35% 45% 55% 65% 75% 85% 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 input voltage (volts dc) input current (ma) efficiency 500ma load 250ma load 50ma load 500ma load 250ma load 50ma load 7803sr ef ciency 7803sr input current 0 50 100 150 200 250 300 350 400 450 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 input voltage (volts dc) 45% 50% 55% 60% 65% 70% 75% 80% 85% 90% 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 input voltage (volts dc) 500ma load 250ma load 50ma load 500ma load 250ma load 50ma load input current (ma) efficiency 7805SR input current vin = 9v vin = 9v vin = 18v vin = 9v vin = 9v vin = 18v
high-efficiency switching regulators 78sr series datel, inc. 11 cabot boulevard, mansfield, ma 02048-1151 tel: (508) 339-3000 (800) 233-2765 fax: (508) 339-6356 ww.datel.com e-mail: sales@datel.com www.cdpowerelectronics.com datel makes no representation that the use of its products in the circuits described herein, or the use of other technical info rmation contained herein, will not infringe upon existing or future patent rights. the descriptions contained herein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. speci? cations are subject to change without notice. the datel logo is a registered datel, inc. trademark. datel (uk) ltd. tadley, england tel: (01256)-880444 internet: www.datel-europe.com e-mail: datel.ltd@datel.com datel s.a.r.l. montigny le bretonneux, france tel: 01-34-60-01-01 internet: www.datel-europe.com e-mail: datel.sarl@datel.com datel gmbh mnchen, germany tel: 89-544334-0 internet: www.datel-europe.com e-mail: datel.gmbh@datel.com datel kk tokyo, japan tel: 3-3779-1031, osaka tel: 6-6354-2025 internet: www.datel-co.jp e-mail: salestko@datel.co.jp, salesosa@datel.co.jp datel china shanghai, china tel: 011-86-51317131 e-mail: davidx@datel.com iso 9001:2000 registered ds-0540c 9/04 ? ? a subsidiary of c&d technologie s mechanical speci cations mechanical dimensions: inches (mm) tolerances: 2 pl dec 0.02 (0.51) 3 pl dec 0.010 (0.254) datel part no. output voltage output current input voltage standard pin package 7803sr +3.3vdc 0.5a +7.5-36vdc 7805SR +5.0vdc 0.5a +7.5-36vdc 7812sr +12.0vdc 0.4a +15-36vdc horizontal pin package 7803srh +3.3vdc 0.5a +7.5-36vdc 7805SRh +5.0vdc 0.5a +7.5-36vdc 7812srh +12.0vdc 0.4a +15-36vdc ordering information figure 1. typical connections 7812sr ef ciency 65% 70% 75% 80% 85% 90% 95% 100% 14 16 18 20 22 24 26 28 30 32 34 36 38 40 input voltage (volts dc) 0 50 100 150 200 250 300 350 400 14 16 18 20 22 24 26 28 30 32 34 36 38 40 input voltage (volts dc) 400ma load 200ma load 40ma load 400ma load 200ma load 40ma load input current (ma) efficiency 7812sr input current 1 2 3 +5vdc @ 500ma +7.5 - 36vdc +v in +v out 7805SR gnd gnd +v in +v out gnd 1 1 0.75 (19.1) 0.41 (10.4) output (+v out ) pc-board hole: 0.037 - 0.043 (0.94 - 1.09) dia. gnd input (+v in ) 0.21 (5.3) pins: 0.025 (0.64) sq. 0.100 (2.54) centers 0.15 (3.8) min. 0.19 (4.8) 123 pc-board hole: 0.037 - 0.043 (0.94 - 1.09) dia. pins: 0.025 (0.64) sq. 0.100 (2.54) centers l1 horizontal package (h pin option) 0.15 (3.8) min. 0.35 (8.9) max. l1 standard package output (+v out ) gnd input (+v in ) 123
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