LM2694EVAL National Semiconductor, LM2694EVAL Datasheet
LM2694EVAL
Specifications of LM2694EVAL
Related parts for LM2694EVAL
LM2694EVAL Summary of contents
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... Features n Integrated N-Channel buck switch n Integrated start-up regulator n Input Voltage Range 30V Basic Step Down Regulator © 2006 National Semiconductor Corporation n No loop compensation required n Ultra-Fast transient response n Operating frequency remains constant with load current and input voltage variations n Maximum Duty Cycle Limited During Start-Up n Adjustable output voltage n Valley Current Limit At 0 ...
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Connection Diagrams 14-Lead TSSOP Ordering Information Order Number Package Type LM2694SD LLP-10 (3x3) LM2694SDX LLP-10 (3x3) LM2694MT TSSOP-14 LM2694MTX TSSOP-14 www.national.com 20187003 NSC Package Drawing SDA10A SDA10A MTC14 MTC14 2 20187002 10-Lead LLP Supplied As 1000 Units on Tape and ...
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Pin Descriptions PIN NUMBER LLP-10 TSSOP-14 NAME BST 3 4 ISEN 4 5 SGND 5 6 RTN RON/ VCC 10 13 VIN 1,7,8, ...
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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. VIN to RTN BST to RTN SW to RTN (Steady State) ESD Rating (Note 2) Human Body Model BST to VCC VIN to SW BST to SW Electrical Characteristics apply over the full Operating Junction Temperature (T design, or statistical correlation ...
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... Device thermal limitations limit external loading CC Note 4: For detailed information on soldering plastic TSSOP and LLP packages, refer to the Packaging Data Book available from National Semiconductor Corporation. Note 5: Typical specifications represent the most likely parametric norm at 25˚C operation. ...
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Typical Performance Characteristics www.national.com 20187004 FIGURE 20187005 FIGURE 20187006 FIGURE Externally Applied ...
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Typical Performance Characteristics (Continued) 20187007 FIGURE 4. ON-Time vs V and 20187008 FIGURE 5. Voltage at R /SD Pin ON 20187009 FIGURE www.national.com ...
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Typical Application Circuit and Block Diagram www.national.com FIGURE 7. 8 20187010 ...
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Typical Application Circuit and Block Diagram (Continued) FIGURE 8. Startup Sequence 9 20187011 www.national.com ...
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Functional Description The LM2694 Step Down Switching Regulator features all the functions needed to implement a low cost, efficient buck bias power converter capable of supplying at least 0.6A to the load. This high voltage regulator contains a 30V N-Channel ...
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Start-Up Regulator Regulation Comparator The feedback voltage compared to the voltage at the Softstart pin (2.5V). In normal operation (the output voltage is regulated), an on-time period is initiated when the voltage at FB falls ...
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Current Limit Current limit detection occurs during the off-time by monitor- ing the recirculating current through the free-wheeling diode (D1). Referring to Figure 7, when the buck switch is turned off the inductor current flows through the load, into SGND, ...
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Applications Information • 250 kHz S • Minimum load current = 100 mA • Maximum load current = 600 mA • Softstart time = 5 ms. R1 and R2: These resistors set the output voltage, and their ratio ...
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Applications Information Normally a lower value can be used for C1 since the above calculation is a worst case calculation which assumes the power source has a high source impedance. A quality ce- ramic capacitor with a low ESR should ...
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Applications Information (Continued) FIGURE 13. Example Circuit 15 20187031 www.national.com ...
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Applications Information Item C1 C2 C4 FIGURE 14. Efficiency vs Load Current and V Circuit of Figure 13 FIGURE 15. Frequency vs V Circuit of Figure 13 www.national.com (Continued) ...
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Applications Information In Figure 17, Cff is added across R1 to AC-couple the ripple at V directly to the FB pin. This allows the ripple at V OUT to be reduced, in some cases considerably, by reducing R3. In the ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 14-Lead TSSOP-14 Package NS Package Number MTC14 18 ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor manufactures products and uses packing materials that meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...