LM34919EVAL National Semiconductor, LM34919EVAL Datasheet
LM34919EVAL
Specifications of LM34919EVAL
Related parts for LM34919EVAL
LM34919EVAL Summary of contents
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... Integrated N-Channel buck switch ■ Integrated start-up regulator ■ Input Voltage Range 40V Basic Step Down Regulator © 2008 National Semiconductor Corporation ■ No loop compensation required ■ Ultra-Fast transient response ■ Operating frequency remains constant with load current and input voltage ■ ...
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Connection Diagrams Bump Side Ordering Information Order Number Package Type LM34919TL 10-Bump micro SMD LM34919TLX 10-Bump micro SMD www.national.com 30004402 NSC Package Drawing Junction Temperature Range TLP10A1A −40° 125°C TLP10A1A −40° 125°C 2 30004433 Top View ...
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Pin Descriptions Pin Number Name A1 RON/SD On-time control and shutdown A2 RTN Circuit Ground A3 FB Feedback input from the regulated output B1 SGND Sense Ground B3 SS Softstart C1 ISEN Current sense C3 VCC Output from the startup ...
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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 Electrical Characteristics over the full Operating Junction Temperature (T statistical correlation ...
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Symbol Parameter Thermal Shutdown T Thermal shutdown temperature SD Thermal shutdown hysteresis Thermal Resistance θ Junction to Ambient JA 0 LFPM Air Flow Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings ...
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Typical Performance Characteristics Efficiency at 800 kHz Externally Applied V CC www.national.com 30004441 IN 30004404 CC 30004435 6 Efficiency at 2 MHz 30004442 30004405 ON-TIME vs V and R ...
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Voltage at the R ON/SD Typical Application Circuit and Block Diagram Pin Shutdown and Operating Current into V 30004437 7 IN 30004438 30004401 www.national.com ...
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Functional Description The LM34919 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 an N-Channel buck ...
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The operating frequency is approximately: The buck switch duty cycle is approximately equal to: In discontinuous conduction mode current through the induc- tor ramps up from zero to a peak during ...
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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 below 2.5V. The buck ...
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FIGURE 4. Inductor Current - Current Limit Operation N - Channel Buck Switch and Driver The LM34919 integrates an N-Channel buck switch and as- sociated floating high voltage gate driver. The peak current allowed through the buck switch is 1.5A, ...
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L1: The main parameter affected by the inductor is the in- ductor current ripple amplitude (I ). The minimum load cur- OR rent is used to determine the maximum allowable ripple in order to maintain continuous conduction mode, where the ...
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FIGURE 5. Example Circuit FIGURE 6. Efficiency vs. Load Current and V FIGURE 7. Frequency vs 30004421 30004440 (Circuit of Figure 5) IN 30004423 (Circuit of Figure 5) www.national.com ...
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LOW OUTPUT RIPPLE CONFIGURATIONS For applications where lower ripple at V following options can be used to reduce or nearly eliminate the ripple. a) Reduced ripple configuration: In Figure 8, Cff is added across R1 to AC-couple the ripple at ...
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P = Iout 1 where R is the inductor’s DC resistance, and the 1.1 factor approximation for the AC losses expected that the internal dissipation of the LM34919 ...
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Physical Dimensions Note 1.514 mm, ±0.030 1.970 mm, ±0.030 0.60 mm, ±0.075 mm www.national.com inches (millimeters) unless otherwise noted 10 Bump micro SMD Package NS Package Number TLP10A1A 16 ...
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Notes 17 www.national.com ...
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