LM5576MH/NOPB National Semiconductor, LM5576MH/NOPB Datasheet
LM5576MH/NOPB
Specifications of LM5576MH/NOPB
*LM5576MH/NOPB
LM5576MH
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LM5576MH/NOPB Summary of contents
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... TSSOP-20 package featuring an exposed die attach pad for thermal dissipation. The LM5576 is sup- ported by the full suite of WEBENCH Simplified Application Schematic WEBENCH ® registered trademark of National Semiconductor Corporation. © 2010 National Semiconductor Corporation LM5576/LM5576Q Features ■ LM5576Q is an Automotive Grade product that is AEC- Q100 grade 1 qualified (− ...
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Connection Diagram Ordering Information Order Number Package Type LM5576MH Exposed Pad TSSOP-20 MXA20A LM5576MHX Exposed Pad TSSOP-20 MXA20A LM5576QMH Exposed Pad TSSOP-20 MXA20A LM5576QMHX Exposed Pad TSSOP-20 MXA20A * Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for ...
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Pin Descriptions Pin(s) Name 1 VCC Output of the bias regulator 2 SD Shutdown or UVLO input 3, 4 Vin Input supply voltage 5 SYNC Oscillator synchronization input or output The internal oscillator can be synchronized to an external 6 ...
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Pin(s) Name 20 BST Boost input for bootstrap capacitor NA EP Exposed Pad www.national.com Description An external capacitor is required between the BST and the SW pins. A 0.022µF ceramic capacitor is recommended. The capacitor is charged from Vcc via ...
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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 GND IN BST to GND PRE to GND SW to GND (Steady State) BST SD GND CC Electrical Characteristics apply over full Operating Junction Temperature range. V Symbol ...
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Symbol Parameter RAMP GENERATOR Ramp Current 1 Ramp Current 2 PWM COMPARATOR Forced Off-time Min On-time COMP to PWM Comparator Offset ERROR AMPLIFIER Feedback Voltage FB Bias Current DC Gain COMP Sink / Source Current Unity Gain Bandwidth DIODE SENSE ...
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Soft Start Current vs Temperature 20189922 7kΩ L 20189924 Demoboard Efficiency vs I and V OUT IN 20189926 12V IN Error Amplifier Gain/Phase A = 101 ...
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Typical Application Circuit and Block Diagram www.national.com 8 ...
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Detailed Operating Description The LM5576 switching regulator features all of the functions necessary to implement an efficient high voltage buck regu- lator using a minimum of external components. This easy to use regulator integrates a 75V N-Channel buck switch with ...
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Shutdown / Standby The LM5576 contains a dual level Shutdown (SD) circuit. When the SD pin voltage is below 0.7V, the regulator low current shutdown mode. When the SD pin voltage is greater than 0.7V but less ...
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FIGURE 5. Simplified Oscillator Block Diagram and SYNC I/O Circuit Error Amplifier and PWM Comparator The internal high gain error amplifier generates an error signal proportional to the difference between the regulated output voltage and an internal precision reference (1.225V). ...
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The sample & hold DC level illustrated in from a measurement of the re-circulating Schottky diode an- ode current. The re-circulating diode anode should be con- nected to the IS pin. The diode current flows through an internal current sense ...
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Maximum Duty Cycle / Input Drop- out Voltage There is a forced off-time of 500ns implemented each cycle to guarantee sufficient time for the diode current to be sam- pled. This forced off-time limits the maximum duty cycle of the ...
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Application Information EXTERNAL COMPONENTS The procedure for calculating the external components is il- lustrated with the following design example. The Bill of Mate- rials for this design is listed in Table Figure 1 is configured for the following specifications: • ...
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RMS current rating and minimum ripple voltage. A good approximation for the re- quired ripple current rating necessary is I Quality ceramic capacitors with a low ESR should be selected for the input filter. To ...
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R4C5). The error amplifier zero cancels the modulator pole leaving a single pole response at the crossover frequen the loop gain. A single pole response at the crossover frequency yields a very stable loop with 90 ...
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FIGURE 12. VCC Bias from VOUT for 8V < VOUT < 14V FIGURE 13. VCC Bias with Additional Winding on the Output Inductor 17 20189918 20189919 www.national.com ...
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PCB LAYOUT AND THERMAL CONSIDERATIONS The circuit in Figure 1 serves as both a block diagram of the LM5576 and a typical application board schematic for the LM5576 buck regulator there are two loops where cur- rents are ...
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... DIODE, 100V, CENTRAL DIODE, 100V, IR (D1-ALT) INDUCTOR, COOPER NOT USED NOT USED RESISTOR RESISTOR RESISTOR RESISTOR RESISTOR REGULATOR, NATIONAL SEMICONDUCTOR 19 VALUE 2.2µ, 100V 2.2µ, 100V 330p, 100V 0.01µ, 100V 0.01µ, 100V 0.022µ, 100V 0.47µ, 16V 22µ ...
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PCB Layout www.national.com Component Side Solder Side Silkscreen 20 20189929 20189930 20189931 ...
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Typical Schematic for Buck/Boost (Inverting) Application 21 20189942 www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 20-Lead TSSOP Package NS Package Number MXA20A 22 ...
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Notes 23 www.national.com ...
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