mpm_78sr_g00 page 1 of 5 d i g i t a l p a n e l m e t e r s 78xxsr series 3.3v/5v/12v outp uts high- ef?ciency switching regulators with lm78xx pinouts datels 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 +70c 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 (1.5% vs. 5%). all these features combine to make 78sr regulators ideal for new or existing lm7805 & lm7812 applications requiring full-load operation at elevated voltages. 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 C 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 C no external components required C40 to +70c operation at full load; short-circuit protection excellent load (0.2%) and line (0.3%) regulation ideal for powering instrumentation from 9v/12v/24v/28v supplies or batteries can be used with unregulated dc supplies protection technical notes 1. input/output (i/o) filtering: as shown in the noise and ripple graphs, 78sr switch - ing 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 continuous operation (with an additional 20% safety margin) at the highest system voltages and temperatures. adding external output capacitors will also improve the units 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 regulators +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 regulators 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 efficiency 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 over - voltage 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. datel part no. output output input voltage current 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 for updated, full-size data sheets visit: www.cd4power.com
h i g h - e f f i c i e n c y s w i t c h i n g r e g u l a t o r s 78sr series h i g h - e f f i c i e n c y s w i t c h i n g r e g u l a t o r s mpm_78sr_g00 page 2 of 5 d i g i t a l p a n e l m e t e r s www.cd4power.com technical notes (continued) 6. soldering & handling precautions: all units are designed to be hand soldered to pc-boards using no-clean solders (+260c, 5 seconds 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 specifications 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 regulators that are installed with their metal tabs lying flat on the sur - face 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 flat 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 performed at an ambient temperature of +25c 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 regulators i/o pins. 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 2% 1.5% 2% input voltage range ? +7.5-36vdc +7.5-36vdc +15-36vdc line regulation (100% load) 0.3% 0.3% 0.3% load regulation (0-100% load) 0.2% 0.2% 0.2% quiescent current 3ma typ., 5ma max. input current see performance curves efficiency 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 C40 to +70c storage temperature C40 to +85c cooling free air convection humidity (non-condensing) 0 to 85% physical mechanical see mechanical specifications package open-frame sip pins 0.025 (0.64mm) square, tin-plated bronze weight 0.08 ounces (2.2g) pin soldering +260c for 5 seconds ? see technical note 5. ? while these regulators can withstand a continuous short-circuit across their output terminals, they will experience a significant temperature rise. extended short-circuit operation will adversely affect the units reliability . 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 performance/functional specifications typical at t a = +25c typical dropout voltage
h i g h - e f f i c i e n c y s w i t c h i n g r e g u l a t o r s 78sr series mpm_78sr_g00 page 3 of 5 d i g i t a l p a n e l m e t e r s www.cd4power.com 7805SR vin = 12v, i load = 50ma typical performance curves t a 2c, 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
h i g h - e f f i c i e n c y s w i t c h i n g r e g u l a t o r s 78sr series mpm_78sr_g00 page 4 of 5 d i g i t a l p a n e l m e t e r s www.cd4power.com 7812sr efficiency 7812sr input current 7805SR efficiency 7803sr efficiency 7803sr input current 7805SR input current 5 0 5 5 6 0 6 5 7 0 7 5 8 0 8 5 9 0 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 i n p u t v o l t a g e e f f i c i e n c y 0 . 0 0 0 . 0 5 0 . 1 0 0 . 1 5 0 . 2 0 0 . 2 5 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 i n p u t v o l t a g e i n p u t c u r r e n t ( a m p s ) 2 5 % l o a d 1 0 0 % l o a d 5 0 % l o a d 2 5 % l o a d 1 0 0 % l o a d 5 0 % l o a d 6 0 6 5 7 0 7 5 8 0 8 5 9 0 9 5 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 i n p u t v o l t a g e e f f i c i e n c y 0 . 0 0 0 . 0 5 0 . 1 0 0 . 1 5 0 . 2 0 0 . 2 5 0 . 3 0 0 . 3 5 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 i n p u t v o l t a g e i n p u t c u r r e n t ( a m p s ) 2 5 % l o a d 1 0 0 % l o a d 5 0 % l o a d 2 5 % l o a d 1 0 0 % l o a d 5 0 % l o a d 7 0 7 5 8 0 8 5 9 0 9 5 1 0 0 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 i n p u t v o l t a g e e f f i c i e n c y 0 . 0 0 0 . 0 5 0 . 1 0 0 . 1 5 0 . 2 0 0 . 2 5 0 . 3 0 0 . 3 5 0 . 4 0 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 i n p u t v o l t a g e i n p u t c u r r e n t ( a m p s ) 2 5 % l o a d 1 0 0 % l o a d 5 0 % l o a d 2 5 % l o a d 1 0 0 % l o a d 5 0 % l o a d
h i g h - e f f i c i e n c y s w i t c h i n g r e g u l a t o r s 78sr series ds-0540g 04/200 7 ? 2006 c&d technologies, inc. c&d technologies, inc. makes no representation that the use of its products in the circuits described herein, or the use of other technical information 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 c&d technologies, inc. trademark. c&d technologies, inc. 11 cabot boulevard, mans? eld, ma 0204 8 -1151 u.s.a. tel: (508) 339-3000 (800) 233-2765 fax: (508) 339-6356 www.cd4power.com email: sales@cdtechno.com iso 9001 registered usa: tucson (az), tel: (800) 547 2537, email: sales@cdtechno.com canada: toronto, tel: (866) 740 1232, email: toronto@cdtechno.com united kingdom: milton keynes, tel: +44 (0)1908 615232, email: mk@cdtechno.com france: montigny le bretonneux, tel: +33 (0)1 34 60 01 01, email: france@cdtechno.com germany: mnchen, tel: +49 (0)89-544334-0, email: ped.munich@cdtechno.com japan: tokyo, tel: 3-3779-1031, email: sales_tokyo@cdtechno.com osaka, tel: 6-6354-2025, email: sales_osaka@cdtechno.com website: www.cd4power.jp china: shanghai, tel: +86 215 027 3678, email: shanghai@cdtechno.com guangzhou, tel: +86 208 221 8066, email: guangzhou@cdtechno.com mpm_78sr_g00 page 5 of 5 d i g i t a l p a n e l m e t e r s mechanical specifications mechanical dimensions: inches (mm) tolerances: 2 pl dec 0.02 (0.51) 3 pl dec 0.010 (0.254) ? ? 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 ) 0.23 (5.7) pins: 0.025 (0.64) sq. 0.100 (2.54) centers 0.15 (3.8) min. 0.19 (4.8) 1 2 3 l1 standard package new low-profile package for updated, full-size data sheets visit: www.cd4power.com 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. 0.37 (9.3) max. l1 output (+v out ) gnd input (+v in ) 1 2 3 0.07 (1.8)
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