LM2576T Motorola, LM2576T Datasheet
LM2576T
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LM2576T Summary of contents
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... DEVICE TYPE/NOMINAL OUTPUT VOLTAGE LM2576–3.3 LM2576–5 LM2576–12 LM2576–15 LM2576–ADJ LM2576T–XX LM2576TV– –40 to +125 C LM2576D2T– Voltage Option, i.e. 3. and ADJ for Adjustable Output. Motorola, Inc. 1997 Order this document by LM2576/D LM2576 EASY SWITCHER 3.0 A STEP– ...
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... R JC 5.0 C Internally Limited C 5.0 C/W T stg –65 to +150 C – 2.0 kV – 260 150 C MOTOROLA ANALOG IC DEVICE DATA 5.0 V Regulated Output 3.0 A Load ON/OFF Output R2 Voltage Versions ( ) 5 3.3 V 1.7 k 5 11.3 k For adjustable version R1 = open Regulated Output L1 V out Output ...
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... NOTES: 1. External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM2576 is used as shown in the Figure 15 test circuit, system performance will be as shown in system parameters section . 2. Tested junction temperature range for the LM2576: MOTOROLA ANALOG IC DEVICE DATA LM2576 Symbol ...
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... V sat – – 4.2 3 – – – – I stby – – 2.2 2 – – – – MOTOROLA ANALOG IC DEVICE DATA Max Unit nA 25 100 – 200 kHz 52 – – 58 – 1.5 1.8 – 2.0 98 – 5.8 6.9 – 7 ...
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... JUNCTION TEMPERATURE ( C) Figure 6. Quiescent Current Load = 3 Load = 200 mA 8.0 6.0 4 INPUT VOLTAGE (V) MOTOROLA ANALOG IC DEVICE DATA LM2576 (Circuit of Figure 15) 1.4 1.2 I Load = 500 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 75 100 125 0 5.0 6.5 6.0 5.5 5.0 4 150 H R ind = 0 ...
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... Figure 11. Minimum Operating Voltage 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 100 125 –50 –25 Figure 12. Feedback Pin Current Adjustable Version Only – 100 JUNCTION TEMPERATURE ( C) 1.0 1.5 2.0 2.5 3.0 SWITCH CURRENT (A) Adjustable Version Only ' V out 1. Load = 500 100 125 JUNCTION TEMPERATURE ( C) 125 MOTOROLA ANALOG IC DEVICE DATA ...
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... D 5 s/DIV Vout = Output Pin Voltage, 10 V/DIV B: Inductor Current, 2.0 A/DIV C: Inductor Current, 2.0 A/DIV, AC–Coupled D: Output Ripple Voltage, 50mV/dDIV, AC–Coupled Horizontal Time Base: 5 s/DIV MOTOROLA ANALOG IC DEVICE DATA LM2576 (Circuit of Figure 15) Figure 14. Load Transient Response 100 mV Output 0 Voltage Change – 100 mV 3 ...
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... Another sensitive part of the circuit is the feedback important to keep the sensitive feedback wiring short. To assure this, physically locate the programming resistors near to the regulator, when using the adjustable version of the LM2576 regulator. V out C out 1000 F Load V out 5,000 out 1000 F Load R1 MOTOROLA ANALOG IC DEVICE DATA ...
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... V out – L(off) L MOTOROLA ANALOG IC DEVICE DATA LM2576 PIN FUNCTION DESCRIPTION Description (Refer to Figure 1) DESIGN PROCEDURE This period ends when the power switch is once again turned on. Regulation of the converter is accomplished by varying the duty cycle of the power switch possible to ...
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... Inductor Selection (L1) A. Use the inductor selection guide shown in Figures 19. B. From the selection guide, the inductance area intersected by the 15 V line and 3.0 A line is L100. C. Inductor value required is 100 H. From Table 2 , choose an inductor from any of the listed manufacturers. 2L Example MOTOROLA ANALOG IC DEVICE DATA ...
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... LM2576 to be able to withstand a continuous output short. B. The reverse voltage rating of the diode should be at least 1.25 times the maximum input voltage. MOTOROLA ANALOG IC DEVICE DATA LM2576 Example 5. Output Capacitor Selection (C out ) A. C out = 680 F to 2000 F standard aluminium electrolytic. ...
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... Inductance Region = H150 D. Proper inductor value = 150 H Choose the inductor from Table Output Capacitor Selection (C out ) out To achieve an acceptable ripple voltage, select C out = 680 F electrolytic capacitor Example + x 1000 13, 300 x 332 150 MOTOROLA ANALOG IC DEVICE DATA ...
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... H330 20 18 L680 L470 16 L330 L220 L150 15 14 0.3 0.4 0.5 0.6 0.8 1 MAXIMUM LOAD CURRENT (A) 300 250 200 150 100 0.3 MOTOROLA ANALOG IC DEVICE DATA LM2576 60 H1000 H680 40 20 L680 9.0 8.0 L47 7.0 1.5 2.0 2.5 3.0 0.3 0 H1500 30 H1000 25 H220 H150 22 20 L680 19 18 ...
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... MBRD340 50 V MBR350 SK35 31DQ05 30WQ05 SR305 60 V MBR360 MBRS360T3 50SQ080 DQ06 MBRD360 SR306 NOTE: Diofes listed inbold are available from Motorola. Table 2. Inductor Selection by Manufacturer’s Part Number Inductor Inductor Code Value L47 47 H L68 68 H L100 100 H L150 150 H ...
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... Standard aluminium electrolytics could be adequate for some applications but for quality design, low ESR types are recommended. MOTOROLA ANALOG IC DEVICE DATA LM2576 Phone + 1–619–674–8100 Fax + 1– ...
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... When multiple switching regulators are located on the same printed circuit board, open core magnetics can cause interference between two or more of the regulator circuits, especially at high currents due to mutual coupling. A toroid, pot core or E–core (closed magnetic structure) should be used in such applications. MOTOROLA ANALOG IC DEVICE DATA ...
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... HORIZONTAL TIME BASE: 5.0 s/DIV Minimizing the Output Ripple In order to minimize the output ripple voltage it is possible to enlarge the inductance value of the inductor L1 and/or to use a larger value output capacitor. There is also another way MOTOROLA ANALOG IC DEVICE DATA LM2576 Figure 24. Discontinuous Mode Switching Current 0.4 A Inductor ...
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... A to the output when the input voltage higher. At lighter loads the minimum input voltage required drops to approximately 4.7 V, because the buck–boost regulator topology can produce an output voltage that, in its absolute value, is either greater or less than the input voltage. MOTOROLA ANALOG IC DEVICE DATA Feedback ...
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... O x 1.0 where and f osc osc in O Under normal continuous inductor current operating conditions, the worst case occurs when minimal. MOTOROLA ANALOG IC DEVICE DATA LM2576 Figure 27. Inverting Buck–Boost Regulator Unregulated DC Input + 100 F 0.1 F /50 V ...
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... A version of this circuit for buck–boost converter is shown in Figure 33. Resistor R3 pulls the ON/OFF pin high and keeps the regulator off until the input voltage reaches LM2576– ON/OFF 3 Gnd 0 MOTOROLA ANALOG IC DEVICE DATA ...
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... V Max Unregulated DC Input +V in LM2574–Adj Gnd 5 ON/OFF 100 F MOTOROLA ANALOG IC DEVICE DATA LM2576 Under normal continuous inductor current operating conditions, the worst case occurs when minimal. (Q1) Figure 33. Undervoltage Lockout Circuit for Buck–Boost Converter + ...
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... Aluminium Electrolytic D1 – 3 Schottky Rectifier, 1N5822 L1 – 150 H, RL2444, Renco Electronics Figure 37. Printed Circuit Board Layout ON/OFF Gnd out MOTOROLA ANALOG IC DEVICE DATA Regulated Output V out1 = 5 3 out 1000 F /16 V Gnd out Copper Side NOTE: Not to scale. ...
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... National Semiconductor LM2576 Data Sheet and Application Note National Semiconductor LM2595 Data Sheet and Application Note Marty Brown “Practical Switching Power Supply Design”, Academic Press, Inc., San Diego 1990 Ray Ridley “High Frequency Magnetics Design”, Ridley Engineering, Inc. 1995 MOTOROLA ANALOG IC DEVICE DATA LM2576 Feedback L1 ...
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... PLASTIC PACKAGE CASE 314B–05 ISSUE J C OPTIONAL E CHAMFER 0.24 (0.610 SEATING –T– PLANE MOTOROLA ANALOG IC DEVICE DATA INCHES MILLIMETERS DIM MIN MAX MIN MAX A 0.572 0.613 14.529 15.570 B 0.390 0.415 9.906 10.541 C 0.170 0.180 4.318 4 ...
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... OPTIONAL A CHAMFER 0.010 (0.254 MOTOROLA ANALOG IC DEVICE DATA LM2576 OUTLINE DIMENSIONS D2T SUFFIX PLASTIC PACKAGE CASE 936A– PAK) ISSUE A –T– TERMINAL NOTES: 1 DIMENSIONING AND TOLERANCING PER ANSI Y14 ...
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... Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. “ ...
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... How to reach us: USA / EUROPE / Locations Not Listed: Motorola Literature Distribution; P.O. Box 5405, Denver, Colorado 80217. 1–303–675–2140 or 1–800–441–2447 Customer Focus Center: 1–800–521–6274 Mfax : RMFAX0@email.sps.mot.com – TOUCHTONE 1–602–244–6609 Motorola Fax Back System – US & Canada ONLY 1–800–774–1848 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 – ...