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. applications in which 78sr regulators are located more than 24 inches (61cm) from the input power supply should include an external 47uf/50v (or greater) aluminum electrolytic capacitor, connected as close as possible to the regulator s +vin and gnd terminals (pins 1 and 2). an external input capacitor is particularly important if the input voltage is applied to the regulator via a mechanical switch or relay. contact bounce at turn-on can produce large inductive current-spikes, and these current spikes can generate damaging voltage transients at the regulator s input terminals. 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 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 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 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 ? 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. 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. 8. dropout voltage: 78sr series regulators described in this data sheet specify a minimum input voltage at which full-load accuracy and output regulation are guaranteed (7.5v for 7803sr and 7805sr, and 15.0v for 7812sr). however, these devices will stay in regulation at lower input voltages if they are operated at less than their rated loads. the following dropout-voltage data, derived from sample testing per- formed at an ambient temperature of +25? with resistive loads, should be used for information purposes only. for these tests, a unit was considered to be out of regulation when its output changed by more +/-0.005vdc from its nominal value. all voltages were measured directly at the regulator s i/o pins. 0% load 25% load 50% load 100% load 7803sr 6.0v 6.2v 6.2v 6.3v 7805sr 6.3v 6.2v 6.2v 6.8v 7812sr 12.8v 13.0v 12.8v 13.0v typical dropout voltage technical notes (continued) 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 performance/functional speci cations typical at t a = +25?
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 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 transient response - 90% load step 7805sr vin = 12v, i load = 500ma 7812sr vin = 24v, i load = 40ma 7812sr vin = 24v, i load = 400ma 7812sr 100% to 10% load step 7805sr 10% to 100% load step 7805sr 100% to 10% load step 7812sr 10% to 100% load step 7803sr vin = 12v, i load = 50ma 7803sr vin = 12v, i load = 500ma 7803sr 10% to 100% load step 7803sr 100% to 10% load step vin = 9v vin = 9v vin = 18v vin = 9v vin = 9v vin = 18v
high-efficiency switching regulators 78sr series 4 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 7812sr ef ciency 7812sr input current 7805sr ef ciency 7803sr ef ciency 7803sr input current 7805sr input current 50 55 60 65 70 75 80 85 90 8 1012141618202224262830323436 input voltage efficiency 0.00 0.05 0.10 0.15 0.20 0.25 8 1012141618202224262830323436 input voltage input current (amps) 25% load 100% load 50% load 25% load 100% load 50% load 60 65 70 75 80 85 90 95 8 1012141618202224262830323436 input voltage efficiency 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 8 1012141618202224262830323436 input voltage nput current (amps) 25% load 100% load 50% load 25% load 100% load 50% load 70 75 80 85 90 95 100 14 16 18 20 22 24 26 28 30 32 34 36 input voltage efficiency 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 14 16 18 20 22 24 26 28 30 32 34 36 input voltage input current (amps) 25% load 100% load 50% load 25% load 100% load 50% load
78sr series high efficiency switching regulators 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-0540d 11/04 ? ? 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) pc-board hole: 0.037 - 0.043 (0.94 - 1.09) dia. pins: 0.025 (0.64) sq. 0.100 (2.54) centers horizontal package (h pin option) 0.15 (3.8) min. 0.35 (8.9) max. l1 output (+v out ) gnd input (+v in ) 123 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 l1 standard package
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