3a, 52khz, step-down switching regulat or lm2576hv feb. 2014 ? r1.0 - 1 - htc features ? step-down switching regulator ? adjustable version output voltage range, 1.23v to 52v 4% max over line and load conditions ? guaranteed output current of 3a ? fixed output voltages : 3.3v, 5.0v, 12v and 15v ? wide input voltage range 60v ? 52 khz fixed frequency oscillator ? ttl shutdown capability, low power standby mode ? requires only 4 external components ? high efficiency ? use readily available standard inductors ? available in to-220, to-263 and sop-8pp packages ? thermal shutdown and current limit protection ? moisture sensitivity level 3 application ? simple high-efficiency step-down (buck) regulator ? efficient pre-regulator for linear regulators ? on-card switching regulators ? positive to negative converter (buck-boost) descripsion sop-8pp pkg to-263 pkg to-220 pkg ordering information device package lm2576hvdp-adj sop-8pp 8l lm2576hvdp-x.x LM2576HVR-ADJ to-263 5l lm2576hvr-x.x lm2576hvt-adj to-220 5l lm2576hvt-x.x x.x = output voltage = 3.3, 5.0, 12, 15 the lm2576hv series of regulators are monolithic integrated circuits that pr ovide all the active functions for a step-down (buck) switching regulator, capable of driving 3a load with excellent line and load regulation. these devices are available in fixed output voltages of 3.3v, 5.0v, 12v, 15v and adjustable output versions. requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator. the lm2576hv series offers a high-efficiency replacement for popular three-terminal linear regulators. it substantially reduces the size of the heat sink, and in some cases no heat sink is required. a standard seri es of inductors optimized for use with the lm2576hv are available from several different manufacturers. this f eature greatly simplifies the design of switch-mode power supplies. other features include a gua ranteed 4% tolerance on output voltage within specified input voltages and output load conditions, and 10% on the oscillator freq uency. external shutdown is included, featuring 50ua (typical) standby current. the output switch includes cycle- by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions. absolute maximum ratings (note 1) characteristic symbol min. max. unit input supply voltage v in - 63 v on/off pin input voltage -0.3 + v in v output voltage to ground (steady state) -0.75 v lead temperature (soldering, 5 sec) t sol 260 storage temperature range t stg -65 150 maximum junction temperature range t jopr - 150
3a, 52khz, step-down switching regulat or lm2576hv feb. 2014 ? r1.0 - 2 - htc operating ratings characteristic symbol min. max. unit supply voltage v in - 60 v temperature range t j -40 125 v ordering information v out package order no. description supplied as status adj sop-8pp 8l lm2576hvdp -adj 3a, 52khz, adjustable reel contact us to-263 5l lm2576hvr -adj 3a, 52khz, adjustable reel contact us to-220 5l lm2576hvt -adj 3a, 52khz, adjustable tube contact us 3.3v sop-8pp 8l lm2576hvdp -3.3 3a, 52khz, fixed reel contact us to-263 5l lm2576hvr -3.3 3a, 52khz, fixed reel contact us to-220 5l lm2576hvt -3.3 3a, 52khz, fixed tube contact us 5.0v sop-8pp 8l lm2576hvdp -5.0 3a, 52khz, fixed reel contact us to-263 5l lm2576hvr -5.0 3a, 52khz, fixed reel contact us to-220 5l lm2576hvt -5.0 3a, 52khz, fixed tube contact us 12v sop-8pp 8l lm2576hvdp -12 3a, 52khz, fixed reel contact us to-263 5l lm2576hvr -12 3a, 52khz, fixed reel contact us to-220 5l lm2576hvt -12 3a, 52khz, fixed tube contact us 15v sop-8pp 8l lm2576hvdp -15 3a, 52khz, fixed reel contact us to-263 5l lm2576hvr -15 3a, 52khz, fixed reel contact us to-220 5l lm2576hvt -15 3a, 52khz, fixed tube contact us root name product code lm 2576hv dp : sop8-pp package type t : to-220-5l r : to-263-5l output voltage : adj / 3.3v / 5.0v /12v
3a, 52khz, step-down switching regulat or lm2576hv feb. 2014 ? r1.0 - 3 - htc pin configuration sop-8pp to-263 to-220 pin description pin no. to-263 / to-220 5 lead sop-8pp 8 lead name function name function 1 vin input supply vin input supply 2 vout output voltage vout output voltage 3 gnd ground fb / adj output voltage feedback or output adjust 4 fb / adj output voltage feedback or output adjust on/off on/off shutdown 5/ 6/ 7/ 8 on/off on/off shutdown gnd ground * exposed pad of sop8-pp package should be externally connected to gnd. typical application - fixed output voltage version l1 100uh c out 1000uf d1 regulated output 5v c in 100uf input voltage vin output feed back on/off gnd lm2576hv + + vin 1. vout 2. fb/adj 3. on/off 4. 8. gnd 7. gnd 6. gnd 5. gnd 5. on/off 4. fb/adj 3. gnd 2. vout 1. vin 5. on/off 4. fb/adj 3. gnd 2. vout 1. vin
3a, 52khz, step-down switching regulat or lm2576hv feb. 2014 ? r1.0 - 4 - htc electrical characteristics specifications with standard type face are for t j = 25 and those with boldface type appl y over full operating temperature range. unless otherwise specified, v in =12v for the 3.3v, 5v, and adjustable version, v in =25v for the 12v version, and v in =30v for the 15v version, i load =500ma. parameter symbol test condition (note 2) min. typ. max. unit system parameters (note 3) feedback voltage v fb lm2576hv-adj v in =12v, i load =0.5a 1.217 1.230 1.243 v 0.5a i load 3a , 8v v in 55v 1.193 1.180 1.230 1.273 1.286 v output voltage v o lm2576hv-3.3 v in =12v, i load =0.5a 3.234 3.300 3.366 v 0.5a i load 3a , 6v vi n 55v 3.168 3.135 3.300 3.450 3.482 v lm2576hv-5.0 v in =12v, i load =0.5a 4.900 5.000 5.100 v 0.5a i load 3a , 8v v in 55v 4.800 4.750 5.000 5.225 5.275 v lm2576hv-12 v in =25v, i load =0.5a 11.76 12.00 12.24 v 0.5a i load 3a , 15v v in 55v 11.52 11.40 12.00 12.54 12.66 v lm2576hv-15 v in =25v, i load =0.5a 14.70 15.00 15.30 v 0.5a i load 3a , 18v v in 55v 14.40 14.25 15.00 15.68 15.83 v efficiency lm2576hv-adj v in =12v, i load =3a, vo = 5v 77 % lm2576hv-3.3 v in =12v, i load =3a 75 % lm2576hv-5.0 v in =12v, i load =3a 77 % lm2576hv-12 v in =15v, i load =3a 88 % lm2576hv-15 v in =18v, i load =3a 88 % device parameters feedback bias current i b v o = 5v (adjustable version only) 50 100 500 na oscillator frequency f o (note 8) 47 42 52 58 63 khz saturation voltage v sat i o = 3a (note 4) 1.4 1.55 1.70 v max duty cycle(on) dc (note 5) 93 98 % current limit i cl (note 4, 8) 4.2 3.5 5.8 6.9 7.5 a
3a, 52khz, step-down switching regulat or lm2576hv feb. 2014 ? r1.0 - 5 - htc (continued) parameter symbol test condit ion min. typ. max. unit output leakage current i l (notes 6, 7) output=0v 7.5 ma quiescent current i q (note 6) 5 10 ma standby quiescent current i stby on/off pin = 5v (off) v in = 60v 50 200 ua on /off control on /off pin logic input level v ih v o = 0v 2.2 2.4 1.4 v v il v o = nominal output voltage 1.2 1.0 0.8 v on /off pin input current i ih on /off pin = 5v (off) 12 30 ua i il on /off pin = 0v (on) 0 10 ua note 1. absolute maximum ratings indicate limits beyond which damage to the device may occur. operating ratings indicate condit ions for which the device is intended to be functional , but do not guarantee specific performan ce limits. for guaranteed specifications and test conditions, see the electr ical characteristics. note 2. all limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). note 3. external components such as the catch diode, inductor, input an d output capacitors can affect switching regulator system performance. when the 2576hv is used as shown in the figure 2 test circuit, system performanc e will be as shown in system parameters section of elec trical characteristics. note 4. output pin sourcing current. no diode, inductor or capacitor connected to output. note 5. feedback pin removed from output and connected to 0v. note 6. feedback pin removed from output and connected to +12v for the ad justable, 3.3v, and 5v, versions, and +25v for the 12v and 15v versions, to force the output transistor off. note 7. v in =60v. note 8. the oscillator frequency reduces to approximately 11 khz in the ev ent of an output short or an overload which causes the regula ted output voltage to drop approximately 40% from the nominal output voltage. this self protections feature lowers the average powe r dissipation of the ic by lowering the minimum dut y cycle from 5% down to approximately 2%.
3a, 52khz, step-down switching regulat or lm2576hv feb. 2014 ? r1.0 - 6 - htc typical operating characteristic
3a, 52khz, step-down switching regulat or lm2576hv feb. 2014 ? r1.0 - 7 - htc application information as in any switching regulator, layout is very impo rtant. rapidly switching currents associated with wiring inductance generate voltage transients which can cause problems. for minimal inductance and ground loops, the length of the leads indicated by heavy lines should be kept as short as possible. single-point grounding (as indicated) or ground plane construction should be used for best results. when using the adjustable version, physically locate the programming resistors near the regulator, to keep the sensitive feedback wiring short. - fixed output voltage version l1 100uh c out 1000uf regulated output 5v c in 100uf input voltage vin output feed back on/off gnd lm2576hv + + d1 mbr360 - adjustable output voltage version l1 100uh r2 r1 c out 1000uf regulated output 5v c in 100uf input voltage vin output feed back on/off gnd lm2576hv + + d1 mbr360 * ) 1 r 2 r + 1 ( v = v ref out * 1) - v v r1( = r2 ref out where v ref = 1.23v, r1 between 1k ? and 5k ? . - c in : 100uf, 75v, aluminum electrolytic - c out : 1000uf, 25v, aluminum electrolytic - d1 - schottky, mbr360 - l1 : 100uh, pulse eng. pe-92108 - r1 : 2k, 0.1% - r2 : 6.12k, 0.1%
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