LM1576-15

LM1576-15 NSC | Alldatasheet

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APR__g r ZZ National oeenecson | a Semiconductor NI LM1576-15/LM2576-15 ro g A i ™ Simple Switcher™ 3 Amp Step-Down Voltage Regulator E General Description Features N The LM1576 series of regulators are monolithic integrated | ™ 15V output, +3% max over line and load conditions “N circuits that provide all the active functions for a step-down ™ Guaranteed 3A output current o> (buck) switching regulator. These devices feature a 15V out- = Wide input voltage range, 17V to 40V —_ put capable of driving a 3A load with excellent line and load Requires only 4 external components a regulation. 1 52 kHz fixed frequency internal oscillator ” Requiring a minimum number of external components, @ Low power standby mode, Ig typically < 200 pA EI these regulators are simple to use and include internal fre- ™ 88% efficiency quency compensation and a fixed-frequency oscillator. @ Uses realy avaliable standard inductore aod The LM1576 series offers a high efficiency replacement for g Thermal shutdown and current limit protection @ popular three-terminal linear regulators. It substantially re- 5 “ - i i?) duces the size of the heat sink, and in many cases no heat = 100% electrical thermal limit burn-in = > sink is required. «as =. A standard series of inductors are available from several Applications tep-d buck lat ir) different manufacturers optimized for use with the LM1576 imple high-efficiency step-down (buck) regulator > series. This feature greatly simplifies the design of switch- ™ Efficient pre-regulator for linear regulators ® mode power supplies. = On-card switching regulators ; aS Other features include a guaranteed +3% tolerance on out- 1 Positive to Negative converter (Inverting, Buck-Boost) put voltage within specified input voltages and output load‘ |solated Flyback Converter using minimum number of | J> conditions, and + 10% on the oscillator frequency. External external components 3 shutdown is included, featuring less than 200 »A standby ™ Negative Boost Converter Bo} current. The output switch includes cycle-by-cycle current on limiting, as well as thermal shutdown for full protection un- ~ der fault conditions. @ es i Typical Application 9 FEEDBACK = 17V=40V +, OC PUT ' OUTST _ nny REGULATED < 2 220 pH OUTPUT thw Steno SJon/orr dior : Cour F Q Tr” AF 1N5822 TL H S Note: Pin numbers are for TO-220 Package = = = = = ‘TL/H/11072-1 e Connection Diagrams Fy

4 Lead TO-3 (K) 5 Lead TO-220 (T) e

a oureut = O—— hi 2 ° — 0 ns ° pO (5 > cround a] ON/OFF: FEEDBACK —— 6 Case is Ground TLH/11072-3 - Bottom View TUH/11072-2 Top View Order Number LM1576K-15, LM2576K-15, Order Number LM2576T-15 See NS Package Number KO4A See NS Package Number TO5A For information about LM2576 in Dual-In-Line or Surface-Mount packages, contact the factory. Patent Pending Simple Swiicher™ i @ trademark of National Semiconductor Corporation ©1990 Natonal Somiconductoe Corporation TL/H/11072 4 FRRO-B20M120/Printedin U.S.A

Absolute Maximum Ratings (note 1) If Military/Aerospace specified devices are required, Lead Temperature please contact the National Semiconductor Sales (Soldering, 10 seconds) 260°C Office/Distributors for availability and specifications. Maximum Junction Temperature 150°C Maximum Supply Voltage LM1576/LM2576 45V Operating Ratings ON/OFF Pin Input Voltage -0.3V<V< +40V Temperature Range Output Voltage to Ground (Steady State) -1V M1576 —55°C < Ty s +150°C Power Dissipation Internally Limited LM2576 40°C < Ty < +125°C Storage Temperature Range —65°C to + 150°C Supply Voltage . . LM1576/LM2576 40V Minimum ESD Rating (C = 100 pF, R = 1.5k9) 2kVv Electrical Characteristics specifications with standard type face are for T) = 25°C, and those with boldface type apply over full Operating Temperature Range. Unless otherwise specified, Vij = 25V, and ILoap = 500 mA. LM2576-15 Symbol Typ Limit (unite) (Note 3) SYSTEM PARAMETERS (Note 4) Test Circuit Figure 7 Vout | Output Voltage Vin = 25V, ILoap = 0.5A 15 v Circuit of Figure 1 14.70 V(Min)

15.30 V(Max)

Vout _ | Output Voltage 0.5A < ILoap < 3A, 18V < Vin < 40V Vv Ey Efficiency Vin = 18V, loan = 3A, Vout = 15V 88 % DEVICE PARAMETERS. fo Oscillator Frequency (Note 10) kHz 47/43 47/42 kHz(Min) 58/62 58/63 kHz(Max) Vsat Saturation Voltage lout = 3A (Note 5) 14 v DC Max Duty Cycle (ON) (Note 6) % %(Min) lot Current Limit Peak Current, Ton < 3 us (Note 5) A I Output Leakage Current | Vij = 40V, (Note 7) Output = 0V 2 mA(Max) Output = —1v | 7.5 mA Output = -1V 30 mA(Max) la Quiescent Current (Note 7) mA 10/12 mA(Max) Istay | Standby Quiescent ON/OFF Pin = 5V (OFF) pA Current 200/500 p-A(Max) On Thermal Resistance K Package, Junction to Ambient 35 Osc K Package, Junction to Case 15 Cay T Package, Junction to Ambient (Note 8) | 65 °C/W ON/OFF CONTROL Test Circuit Figure 1 Vit Logic Input Level Vout = 15V 12 1.0/0.8 1.0/0.8 v(Max) hw ON/OFF Pin Input ON/OFF Pin= 5V (OFF) pA Current pA(Max) te ON/OFF Pin = OV (ON) pA »A(Max)

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: Ail limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). Ali limits are used to calculate Average Outgoing Quality Level, and all are 100% production tested. Note 3: All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% Production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Contro! (SQC) methods. Note 4: External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM1576/LM2576 is used as shown in the Figure 1 test circuit, system performance will be as shown in system parameters section of Electrical Characteristics. Note 5: Output (pin 2) sourcing current. No diode, inductor or capacitor connected to output. Note 6: Feedback (pin 4) removed from output and connected to OV. Note 7: Feedback (pin 4) removed from output and connected to 25V to force the output transistor OFF. Note 8: Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically, with / inch leads in a socket, or on a PC board with minimum copper area surrounding the leads. Note 9: Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically, with //, inch leads soldered to a PC board containing approximately 4 square inches of copper area. Note 10: The oscillator frequency reduces to approximately 18 kHz in the event of an output short or an overload which pulls the 15V output lower than 9V. This ‘self protection feature lowers the average power dissipation of the IC by lowering the minimum duty cycle from 5% down to approximately 2%. Typical Performance Characteristics (circuit of Figure 1) Normalized ‘eo Output Voltage em Line Regulation 29 Dropout Voltage ~ Ef | ftir on | gf Hea || 2 os ope Pattie 2 as | | |} e LIT 2 oft ee g o |) Tee Bop eee | PAN PCC | aS 3 “4 aan | |] 1 TTI 2 Litt itty ooo Ltt tT TTT] oe a * LETT JUNCTION TEMPERATURE (°C) INPUT VOLTAGE (V) JUNCTION TEMPERATURE (°C) Standby Current Limit Supply Current Quiescent Current Tite] . (eee) os "ee = “SI 2. Att: Eso [pte rt PLOT PEE MORRSEEEE = N 2 oan = 200 ma = 3 tT Es gS 6 — 50 | eT TT MOOT) EERE EE

1 WLLL TTT ey

JUNCTION TEMPERATURE (°C) INPUT VOLTAGE (¥) JUNCTION TEMPERATURE (°C) ‘Switch Oscillator Frequency Saturation Voltage Efficiency [TT [retuntear 25] | ttt e (OTT TT) e of = » | a ee 2 | shar z ytiws TT To ¢ JANI 3 woe eee Oe | RNG pSRAEE bee zon \\ 2 os I] i “HEH NEY oe a LLL TL def] a. | ft tf Ps TL/H/11072-5

Typical Performance Characteristics (continued) Load Transient Response Switching Waveforms ‘50V — — — +100 mv \\ A 4 Output a ° —_—— a Voltage 0 4 (4A Change | . Pa =100 mv B {2A — - Lo — an 3A Nene (4a pO O 2A Cc | 2A Current 1A \\ ° ———— of Pm OY 0 Pa 100 ps/div 5 ps/div TUH/1 1072-6 TUH/11072-7 A; Output pin voltage, 50V/div B: Output pin current, 2A/div C: Inductor current, 2A/div D: Output ripple voltage, 50 mV/div, AC-coupled Horizontal Time Base: 5 .s/div Test Circuit and Layout Guidelines (Figure 1) FEEDBACK 17V¥=40V +, Oe INPUT ; TOU REGULATED thon Joo "enor: 22004 Tay, OUTPUT Tie 15822 ve Note: Pin numbers are for the TO-220 Package Cin — 100 pF, SOV Aluminum Electyrolytic As in any switching regulator, layout is very important. Rap- Cour— 1000 wF, 25V Aluminum Electyrolytic idly switching currents associated with wiring inductance D1 = — Schottky, 1N5822 generate voltage transients which can cause problems. For L1 — 220 wH, PE-53116 (Pulse Engineering) minimal inductance and ground loops, the length of the 5.Pin TO-220 Socket—2996 (Loranger Mfg. Co.) leads indicated by heavy lines should be kept short as 4-Pin TO-3 Socket—8112-AG7 (Augat Inc.) possible. Single-point grounding (as indicated) or ground plane construction should be used for best results. Block Diagram and Typical Application (Figure 2 it $$ a Cw T [+] = > COMPARATOR vnen o output [2] TOT» onbsoe] [Sz ae Tene] fomen] ish A” p wet Gael E] Bas) Far] SPL E| | oD = = Note: Pin numbers are for the TO-220 Package TL/H/11072-9

1. Inductor Selection (L1) 1. Inductor Selection (L1)

4 CSRS:

2 L330

FIGURE 3. Inductor Value Selection Guide (For Continuous Mode Operation)

415.0926 Pe-52627 AL1962

FIGURE 4. Inductor Selection by Manufacturer's Part Number

LM1576/LM2576 Design Procedure (continued) Procedure Example 2. Output Capacitor Selection (Cour) 2. Output Capacitor Selection (Cour) A. The value of the output capacitor together with the A. Cout = 680 F to 2000 pF standard aluminum inductor defines the dominant pole-pair of the switching electrolytic regulator loop. For stable operation and an acceptable output ripple voltage, (approximately 1% of the output voltage) a value between 680 uF and 2000 pF is recom- mended. The amount of output ripple voltage is primarily a function of the ESR (Equivalent Series Resistance) of the output capacitor. The value and the type of capacitor used will determine the amount of ESR it contains. Selecting a ca- pacitor with a low ESR will result in a low output ripple voltage. In general, the lower capacitor values have the higher ESR ratings. The lower capacitor values (220 »F-500 pF) will allow typically 50 mV to 150 mV of output ripple voltage, while larger value capacitors will reduce the ripple to approxi- mately 35 mV to 50 mV. VrIPPLE p-p 2 0.3 X ILoap(Max) x ESR To further reduce the output ripple voltage, several stan- B. Capacitor voltage rating = 25V dard electrolytic capacitors may be paralleled, or a high- er-grade capacitor may be used. Such capacitors are of- ten called “high-frequency”, “low-inductance”, or “low- ESR”. These will reduce the output ripple to 10 mV to| 3. Catch Diode Selection (D1) 20 mV. However, reducing the ESR below 0.059 can A. For this example, a 30V rating is adequate. cause instability. For this reason, the use of a tantalum B. Use the 1N5821 or 310Q03 Schottky diodes, or capacitor as the sole output capacitor is not recommend- any of the suggested fast-recovery diodes. ed. Tantalum capacitors (because of their good low tem- perature characteristics) can be used in parallel with alu- | __ Schottky | _—_FastRecovery _| minum electrolytics, with the tantalum making up 10% or [aa | 4a-ca_ | 3a__| aa-oa | 20% of the total capacitance. The capacitor's ripple current rating at 52 kHz should be 1N5820 1N5823 at least 50% higher than the ripple component of the 20V MBR320P. inductor current. $R302 IRIPPLE(Max) 2 1.5 x 0.3 X ILOAD(Max) B. The capacitor's voltage rating should be at least 1.25 ‘1N5621 The The times greater than the output voltage. For a 15V regula- 30V MBR330 | S0WQ03 | Following | Following tor, a rating of at least 20V is appropriate, and a 25V or 31DQ03 31DQ03 Diodes Diodes 30V rating is recommended. SR303 1N5824 Are All Are All 3. Catch Diode Selection (D1) 1N5822 | MBR340 | Ratedto | Ratedto The catch-diode current rating must be at least 1.2 times mers40 | 31DQ04 100V 100V greater than the maximum load current. Also, if the power 40V 31DQ04 s50WQ04 supply design must withstand a continuous output short, $R304 1N5825 31DF1 50WF10 the diode should have a current rating equal to the maxi- mum current limit of the LM2576. The most stressful con- MBR350 HER302 | MUR410 dition for this diode is an overload or shorted output con- 50V 31DQ05 HER602 dition. SR305 A. The reverse voltage rating of the diode should be at least 1.25 times the maximum input voltage. MBR360 | 50WQ06 B. Because of their fast switching speed and low forward 60v DaQ06 50SQ060 voltage drop, Schottky diodes provide the best efficiency. SR306 Fast-Recovery, High-Efficiency, or Ultra-Fast Recovery FIGURE 5. Diode Selection Guide diodes are also suitable, but some types with an abrupt hare i i i | prob- lame. ATastrecovery code wih sot roooery character | 72 the simply the buck regulator design procedwe, Nationa i "9 Semiconductor is making available computer design software to be istics is a better choice. Standard 60 Hz diodes (e.g., 4 " , “he 1N4001 or 1N5400, etc.) are also not suitable. See Fig- | U60 with the Simple Switcher line of switching regulators. Switchers ure 5 for Schottky and “soft” fast-recovery diode selec- | Made Simple is available on a (57%4") diskette for IBM compatible tion guide. computers from a National Semiconductor sales office in your area.

the feedback pin, the regulator senses the inverted output the input voltage reaches a predetermined level. current, can be calculated from the following formula: . . . components, etc. to the regulator.

3 ON/oFF

FIGURE 6. Inverting Buck-Boost Develops — 15V

Application Hints (continues) If the operating temperature range includes temperatures The output ripple voltage is due mainly to the inductor saw- below —25°C, the input capacitor value may need to be tooth ripple current multiplied by the ESR of the output ca- larger. With most electrolytic capacitors, the capacitance Pacitor (see section 2A of design procedure). value decreases and the ESR increases with lower temper- The voltage spikes are present because of the fast switch- atures and age. Adding a ceramic or solid tantalum capaci- ing action of the output switch, and the parasitic inductance tor near the input pin will increase the regulator stability at of the output filter capacitor. To minimize these voltage cold temperatures. For maximum capacitor operating life- spikes, special low inductance capacitors can be used, and time, the capacitor's RMS ripple current rating should be their lead lengths must be kept short. Wiring inductance, greater than 1.2 x (ton/T) X ILoap- stray capacitance, as well as the scope probe used to eval- INDUCTOR SELECTION uate these transients, all contribute to the amplitude of The inductor value selection guide of Figure 3 was designed these spikes. ; for buck regulator designs of the continuous inductor cur- An additional smail LC filter (25 »H and 100 pF) can be rent type. When using inductor values shown in the inductor added to the output to further reduce the amount of output selection guide, the peak-to-peak inductor ripple current will ripple and transients. be approximately 20% to 30% of the maximum DC current. FEEDBACK CONNECTION Hin relatively heavy raductor curont aleve fecha but The LM2576-15 feedback circuitry is designed so that, i " ng), when the output voltage is connected directly to the Feed- under fight load conditions, the circuit will be forced to the ri i . i . back pin, the output voltage is 15V. discontinuous mode {inductor current falls to zero for a peri- od of time). This discontinuous mode of operation is perfect- ON/OFF INPUT ly acceptable. For light loads (less than approximately For normal operation, the ON/OFF pin should be grounded 300 mA) it may be desirable to operate the regulator in the or driven with a low-level TTL voltage (typically below 1.6V). discontinuous mode, primarily because of the lower inductor To put the regulator into standby mode, drive this pin with a values required for the discontinuous mode. high-level TTL or CMOS signal. The LM2576 can be used for both continuous and discontin- uous modes of operation. The selection guide chooses in- GROUNDING ductor values suitable for continuous mode operation, but if To maintain output voltage stability, the power ground con- the inductor value chosen is prohibitively high, the designer nections must be low-impedance (see Figure 7). For the should investigate the possibility of discontinuous operation. TO-3 style package, the case is ground. For the 5-lead The computer design software Switchers Made Simple will TO-220 style package, both the tab and pin 3 are ground provide all component values for discontinuous (as well as and either connection may be used, as they are both part of continuous) mode of operation. the same copper lead frame. Inductors are available in different styles such as pot core, HEAT SINK/THERMAL CONSIDERATIONS toroid, E-frame, bobbin core, etc., as well as different core In many cases, only a small heat sink is required to keep the materials, such as ferrites and powdered iron. The least ex- LM2576 junction temperature within the allowed operating Pensive, the bobbin core type, consisting of wire wrapped range. For each application, to determine whether or not a on a ferrite rod core. ins type or construction makes for an heat sink will be required, the following must be identified: inexpensive inductor, but since the magnetic flux is not com- . . i pletely contained within the core, it generates more electro- 1. Maximum ambient temperature (in the application). magnetic interference (EMI). This EMI can cause problems 2. Maximum regulator power dissipation (in application). in sensitive circuits, or can give incorrect scope readings 3. Maximum allowed junction temperature (150°C for because of induced voltages in the scope probe. M1576 or 125°C for the LM2576). For a safe, conserva- The inductors listed in the selection chart include ferrite pot tive design, a temperature approximately 15°C cooler core construction for AIE, powdered iron toroid for Pulse than the maximum temperatures should be selected. Engineering, and ferrite bobbin core for Renco. 4. LM2576 package thermal resistances 0 ja and 0c. An inductor should not be operated beyond its maximum Total power dissipated by the LM2576 can be estimated as rated current because it may saturate. When an inductor follows: begins to saturate, the inductance decreases rapidly and Vo the inductor begins to look mainly resistive (the DC resist- Pp = (Vin) (la) + (<2) (Loan) (VsaT) ance of the winding). This can cause the switch current to IN rise very rapidly and the switch may not be able to turn off where Ig (quiescent current) and Vgar can be found in the fast enough to protect itself from excessive current. Differ- Characteristic Curves shown previously, Vin is the applied ent inductor types have different saturation characteristics, minimum input voltage, Vo is the regulated output voltage, and this should be kept in mind when selecting an inductor. and ILoap is the load current. The dynamic losses during turn-on and turn-off are negligible if a Schottky type catch The inductor manufacturers data sheets include current and diode i " id it 4 liode is used. energy limits to avoid inductor saturation. OUTPUT VOLTAGE RIPPLE AND TRANSIENTS The output voltage of a switching power supply will contain a sawtooth ripple voltage at the switcher frequency, and may also contain short voltage spikes at the peaks of the sawtooth waveform.

Application Hints (continued) When no heat sink is used, the junction temperature rise EQUIVALENT SERIES INDUCTANCE (ESL) can be determined by the following: The pure inductive component of a capacitor (see Figure ATy = (Pp) (8a) 8). The amount of inductance is determined to a large ex- To arrive at the actual operating junction temperature, add tent on the capacitor’s construction. In a buck regulator, this the junction temperature rise to the maximum ambient tem- unwanted inductance causes voltage spikes to appear on perature. the output. Ty = ATS + Ta {f the actual operating junction temperature is greater than the selected safe operating junction temperature deter- WATE mined step 3, then a heat sink is required. €sR ESL. When using a heat sink, the junction temperature rise can TUH/11072-13 be determined by the following: FIGURE 8. Simple Model of a Real Capacitor ATy = (Pp) (@sc + Pintertace + PHeat Sink) CAPACITOR EQUIVALENT SERIES The operating junction temperature will be: RESISTANCE (ESR) Ty=Ta + ATy The purely resistive component of a real capacitor’s imped- F an ance (see Figure 8). It causes power loss resulting in ca- As above, if the actual operating junction temperature is ‘ ; 4 ‘toe greater than the selected sae operating junction tempera. Pacitor heating, which directly affects the capacitor’s oper- ture, then a larger heat sink is required (one that has a lower ating Wfetime. When used as a switching regulator output thermal resistance). filter, higher ESR values result in higher output ripple volt- ages. > Included on the Switchers Made Simple design software is . . p a more precise (non-linear) thermal model that can be used Most ctandar duminum slectrowie Fapactors in ihe to determine junction temperature with different input-output ade capacit. be Pe 9 ESR” “h et vuenoy", ¢ Es - parameters or different component values. It can also calcu- ajuctance") . hn 220 F 1000 ‘on quency”, Sh hove late the heat sink thermal resistance required to maintain Ce ar eee te ean tt 1000 HF range generally haw the regulator’s junction temperature below the maximum of less than 0.152. junction temperature. OUTPUT RIPPLE VOLTAGE . The AC component of the switching regulator's output volt- Definition of Terms age. It is usually dominated by the output capacitor's ESR BUCK Ri multiplied by the inductor's ripple current. The peak-to-peak UCK REGULATOR . . ; value of this sawtooth ripple current will be typically 30% of A swching regulator topology nich a higher voltage s the maximum load current (when the Design Procedure in conver! a lower voltage. Also known as a step-down the datasheet is followed). switching regulator. CAPACITOR RIPPLE CURRENT “BOO! TOR Buck: ST REGULA’ . . cas . RMS value of the maximum allowable alternating current at A switching regulator topology in which a positive voltage is which a capacitor can be operated continuously at a speci- converted to a negative voltage without a transformer. fied temperature. DUTYCYCLE(D) ; ; ; STANDBY CURRENT (Istey) Ratio of the output switch’s on-time to the oscillator period. Supply current required by the LM2576 when in the standby for buck regulator mode (ON/OFF pin is driven to TTL-high voltage), thus turn- Vv ing the output switch OFF. p = !oN _ Your T VIN INDUCTOR RIPPLE CURRENT for buck-boost regulator The peak-to-peak value of the inductor current waveform, b= ton - \\Vol typically a sawtooth waveform when the regulator is operat- a [Vol + Vin ing continuous (vs discontinuous). where T is the oscillator period, typically 1/52 kHz or 19 us. CONTINUOUS/DISCONTINUOUS MODE CATCH DIODE OR STEERING DIODE C enaTON , «Inthe cont de th " 1 1 elates to the inductor current. In the continuous m« , the The diode which p rovides a gun Path for the load current inductor current is always flowing and never drops to zero, . vs the discontinuous mode, where the inductor current EFFICIENCY (n) drops to zero for a period of time. The proportion of input power actually delivered to the load. INDUCTOR SATURATION - n= Pout _ Pout The condition which exists when an inductor cannot hold Pin Pout + PLoss any more magnetic flux. When an inductor saturates, the inductor appears less inductive and the resistive component dominates. Inductor current is then limited only by the DC resistance of the wire and the available source current.

Physical Dimensions inches (mitimeters) 0.880 — 0.915 esse eg) 0.700.775 (19.30—19.69) on6 DIA “T T ies)" 0.060 0.070 4200450 0.025, (0.965 - 1.092} MAX UNCONTROLLED LEAD DIA AaTT=1197 bl (12.45 —12.95) 0.168 - 0.178 ~ 0151-0161 5), IR g lel (3.835 4.089) CIRCLE ne ua neve) Order Number LM1576K-15 or LM2576K-15 wo

5 Lit #107465

3 Physical Dimensions inches (milimeters) (Continued)

0.395-0.420 SEATING PLANE o (1093-1087) 8151 0002 yg 0.180 -0.005 va (2835-0051) sro Pn ' a 0.050 -0,002 (12700-0861) oa T = ‘ (6350-0258) ° 0.110 :0.010 ¥ c 0.340 -0.010 years. = (We36 70268) i} . Xx 7 (2s. 0361) ' Qa o 0.540 -0.015 13.716 0381) E | < UU aa o plik | oaas-oo0s (0301 2%) 105 Sats

2 I osesos2 : as (ear 2)

° F

5 O70

” vw 2 Order Number LM2576T-15. wo rc o i w aS wo

7 LIFE SUPPORT POLICY

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