LM2677T-5.0/NOPB National Semiconductor, LM2677T-5.0/NOPB Datasheet
LM2677T-5.0/NOPB
Specifications of LM2677T-5.0/NOPB
*LM2677T-5.0/NOPB
LM2677T-5.0
Related parts for LM2677T-5.0/NOPB
LM2677T-5.0/NOPB Summary of contents
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... The output voltage is guaranteed to a ±2% toler- ance. Typical Application SIMPLE SWITCHER ® registered trademark of National Semiconductor Corporation © 2008 National Semiconductor Corporation ® High Efficiency 5A Step-Down Features ■ Efficiency up to 92% ■ ...
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... LM2677SD-3.3 3.3 LM2677SDX-3.3 5.0 LM2677SD-5.0 5.0 LM2677SDX-5.0 ADJ LM2677SD-ADJ ADJ LM2677SDX-ADJ www.national.com 10130101 LM2677T-3.3, LM2677T-5.0, LM2677T-12 or LM2677T-ADJ See NSC Package Number TA07B Top View LLP-14 See NS package Number SRC14A Package Marking S0002XB S0002XB S0002YB S0002YB S0002ZB S0002ZB S0003AB S0003AB 2 TO-220 Package ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Input Supply Voltage ON/OFF Pin Voltage Switch Voltage to Ground (Note 12) Boost Pin Voltage Feedback Pin Voltage Power Dissipation Electrical Characteristics of operation, −40°C to 125°C. Specifications appearing in normal type apply for T LM2677-3 ...
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All Output Voltage Versions Electrical Characteristics Limits appearing in bold type face apply over the entire junction temperature range of operation, −40°C to 125°C. Specifications appearing in normal type apply for T justable versions and V =24V for the 12V ...
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Note 2: ESD was applied using the human-body model, a 100pF capacitor discharged through a 1.5 kΩ resistor into each pin. Note 3: Typical values are determined with Note 4: All limits are guaranteed at room ...
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Typical Performance Characteristics Normalized Output Voltage Efficiency vs Input Voltage Switch Current Limit www.national.com 10130109 10130111 Operating Quiescent Current 10130104 6 Line Regulation 10130110 Efficiency vs I LOAD 10130112 10130105 ...
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Standby Quiescent Current 10130140 ON/OFF Pin Current (Sourcing) 10130114 Feedback Pin Bias Current 10130116 ON/OFF Threshold Voltage Switching Frequency 7 10130113 10130115 www.national.com ...
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Continuous Mode Switching Waveforms V = 20V 5V OUT μ 400 μF, C OUT A: V Pin Voltage, 10 V/div Inductor Current, 2 A/div C: Output Ripple Voltage, 20 ...
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Block Diagram * Active Inductor Patent Number 5,514,947 † Active Capacitor Patent Number 5,382,918 9 10130106 www.national.com ...
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... Switchers Made Sim- ple a complete switching power supply can be designed quickly. The software is provided free of charge and can be downloaded from National Semiconductor's Internet site lo- cated at http://www.national.com. SWITCH OUTPUT This is the output of a power MOSFET switch connected di- rectly to the input voltage ...
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DESIGN CONSIDERATIONS FIGURE 1. Basic circuit for fixed output voltage applications. FIGURE 2. Basic circuit for adjustable output voltage applications Power supply design using the LM2677 is greatly simplified by using recommended external components. A wide range of inductors, capacitors ...
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The inductors offered have been specifically manufactured to provide proper operation under all operating conditions of in- put and output voltage and load current. Several part types are offered for a given amount of inductance. Both surface mount and through-hole ...
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... Step 1: Operating conditions are: Vout = 3.3V Vin max = 16V Iload max = 2.5A Step 2: Select an LM2677T-3.3. The output voltage will have a tolerance of ±2% at room temperature and ±3% over the full operating temperature range. Step 3: Use the nomograph for the 3.3V device ,Figure 3. The ...
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The load current re- quired is 2A maximum also desired to implement the power supply with all surface mount components. Step 1: Operating conditions ...
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Inductor Selection Guides For Continuous Mode Operation FIGURE 3. LM2677-3.3 FIGURE 4. LM2677-5.0 10130121 10130122 15 10130123 FIGURE 5. LM2677-12 10130124 FIGURE 6. LM2677-ADJ www.national.com ...
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Inductor Inductance Current Reference (µH) Number L23 33 1.35 L24 22 1.65 L25 15 2.00 L29 100 1.41 L30 68 1.71 L31 47 2.06 L32 33 2.46 L33 22 3.02 L34 3.65 15 L38 68 2.97 L39 47 3.57 L40 ...
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Capacitor Selection Guides Capacitor AVX TPS Series Reference C (µF) WV (V) Code C1 330 C2 100 C3 220 100 C10 22 C11 C12 C13 Capacitor Sanyo OS-CON SA ...
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Nichicon Panasonic AVX Sprague/Vishay Sanyo Kemet www.national.com Capacitor Manufacturer Contact Numbers Phone (847) 843-7500 FAX (847) 843-2798 Phone (714) 373-7857 FAX (714) 373-7102 Phone (845) 448-9411 FAX (845) 448-1943 Phone (207) 324-4140 FAX (207) 324-7223 Phone (619) 661-6322 FAX (619) ...
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TABLE 3. Output Capacitors for Fixed Output Voltage Application Output Inductance Voltage (V) (µ 3 100 Output Inductance Sanyo OS-CON SA Voltage (V) ...
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TABLE 4. Input Capacitors for Fixed Output Voltage Application (Assumes worst case maximum input voltage and load current for a given inductance value) Output Inductance Voltage (V) (µ 3 ...
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TABLE 5. Schottky Diode Selection Table Reverse Surface Mount Voltage More (V) 20V SK32 30V SK33 MBRD835L 30WQ03F 40V SK34 MBRB1545CT 30BQ040 6TQ045S 30WQ04F MBRS340 MBRD340 SK35 50V or More 30WQ05F Diode Manufacturer Contact Numbers Phone International ...
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TABLE 6. Output Capacitors for Adjustable Output Voltage Applications Output Voltage Inductance (V) 1.21 to 2.50 2.5 to 3.75 3. 6.25 6.25 to 7.5 7 12.5 12 ...
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Output Capacitors for Adjustable Output Voltage Applications (continued) Output Voltage Inductance Sanyo OS-CON SA (V) (µH) No. 33* 2 1.21 to 2.50 47* 2 33* 1 2.5 to 3. ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted TO-263 Surface Mount Power Package Order Number LM2677S-3.3, LM2677S-5.0, LM2677S-12 or LM2677S-ADJ NS Package Number TS7B 24 ...
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... TO-220 Power Package Order Number LM2677T-3.3, LM2677T-5.0, LM2677T-12 or LM2677T-ADJ NS Package Number TA07B 14-Lead LLP Package NS Package Number SRC14A 25 www.national.com ...
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