LM34919EVAL National Semiconductor, LM34919EVAL Datasheet
LM34919EVAL
Specifications of LM34919EVAL
Related parts for LM34919EVAL
LM34919EVAL Summary of contents
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... LM34919 Evaluation Board Introduction The LM34919EVAL evaluation board provides the design en- gineer with a fully functional buck regulator, employing the constant on-time (COT) operating principle. This evaluation board provides a 5V output over an input range 40V. The circuit delivers load currents to 600 mA, with current limit set at a nominal 700 mA ...
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Board Layout and Probing The pictorial in Figure 1 shows the placement of the circuit components. The following should be kept in mind when the board is powered: 1) When operating at high input voltage and high load current, forced ...
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Since the output ripple is passed by Cff to the FB pin with little or no attenuation, R4 can be reduced so the minimum ripple ≊ mVp-p. The minimum value for Cff is calculated OUT from: ...
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Monitor The Inductor Current The inductor’s current can be monitored or viewed on a scope with a current probe. Remove R6, and install an appropriate current loop across the two large pads where R6 was located. In this way the ...
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... TDK C3216X7R1C106K Unpopulated Unpopulated Zetex ZLLS2000 SOT23-6 Bussman DR73-150 7 7.6 mm Vishay CRCW06034322F Vishay CRCW06032491F Panasonic ERJ3RQFR39 Unpopulated Vishay CRCW08050000Z National Semiconductor 10 Bump µSMD LM34919TL 5 Value 1210 1.0 µF, 50V 0603 0.1 µF, 50V 0603 0.1 µF, 50V 0603 0.022 µF, 50V 1206 10 µ ...
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Circuit Performance www.national.com 30024210 FIGURE 6. Efficiency vs Load Current 30024211 FIGURE 7. Efficiency vs Input Voltage 6 ...
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FIGURE 8. Output Voltage Ripple FIGURE 9. Switching Frequency vs. Input Voltage FIGURE 10. Load Current Limit vs Input Voltage 7 30024212 30024213 30024214 www.national.com ...
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Typical Waveforms Trace OUT Trace 3 = inductor Current Trace Pin Vin = 24V, Iout = 400 mA Trace OUT Trace 3 = inductor Current Trace Pin Vin ...
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PC Board Layout Board Silkscreen Board Top Layer 9 30024217 30024218 www.national.com ...
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