LM5000-3MTC/NOPB National Semiconductor, LM5000-3MTC/NOPB Datasheet
LM5000-3MTC/NOPB
Specifications of LM5000-3MTC/NOPB
*LM5000-3MTC/NOPB
LM5000-3MTC
Related parts for LM5000-3MTC/NOPB
LM5000-3MTC/NOPB Summary of contents
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... ON/ OFF control. There are two operating frequency ranges avail- able. The LM5000-3 is pin selectable for either 300kHz (FS Grounded) or 700kHz (FS Open). The LM5000-6 is pin se- lectable for either 600kHz (FS Grounded) or 1.3MHz (FS Open). The device is available in a low profile 16-lead TSSOP package or a thermally enhanced 16-lead LLP package ...
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... Connection Diagram Ordering Information Order Number LM5000-3MTC LM5000-3MTCX LM5000SD-3 LM5000SDX-3 LM5000SD-6 LM5000SDX-6 Pin Descriptions Pin Name 1 COMP Compensation network connection. Connected to the output of the voltage error amplifier. The RC compenstion network should be connected from this pin to AGND. An additional 100pF high frequency capacitor to AGND is recommended. ...
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... Error Amp Voltage Gain V D Maximum Duty Cycle MAX LM5000-3 Maximum Duty Cycle LM5000-6 T Minimum On Time MIN Switching Frequency f S LM5000-3 Switching Frequency LM5000-6 I Shutdown Pin Current SHDN I Switch Leakage Current L R Switch R DSON DSON Th SHDN Threshold SHDN UVLO On Threshold Off Threshold ...
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Symbol Parameter θ Thermal Resistance JA Note 1: Absolute maximum ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions for which the device is intended to be functional, but device parameter specifications may not ...
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Typical Performance Characteristics Iq (non-switching (switching Temperature fb = 300kHz Iq (non-switching 20031920 = 300kHz Iq (switching 20031922 20031924 5 @ ...
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Current Limit vs Temperature f vs Low (- vs. Temperature @ FS = Low (-3) SW www.national.com Current Limit vs V 20031926 f vs 20031928 f vs. Temperature @ FS = ...
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Temperature @ FS = Low (-6) SW Error Amp. Transconductance vs Temp. f vs. Temperature @ FS = OPEN (-6) SW 20031974 BYP Pin Voltage vs V 20031932 7 20031975 IN 20031933 www.national.com ...
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FIGURE 1. 300 kHz operation, 48V output FIGURE 2. 700 kHz operation, 48V output 8 20031953 20031954 ...
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... Block Diagram Boost Regulator Operation The LM5000 utilizes a PWM control scheme to regulate the output voltage over all load conditions. The operation can best be understood referring to the block diagram and Figure 3. At the start of each cycle, the oscillator sets the driver logic and turns on the NMOS power device conducting current through the inductor, cycle 1 of Figure 3 (a) ...
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... FIGURE 4. (a) Inductor current. (b) Diode current. The LM5000 is a current mode PWM regulator. The signal flow of this control scheme has two feedback loops, one that senses switch current and one that senses output voltage. To keep a current programmed control converter stable above duty cycles of 50%, the inductor must meet certain cri- teria ...
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... For the purpose of stabilizing the LM5000, choosing a crossover point well below where the right half plane zero is located will ensure sufficient phase margin. A discussion of the right half plane zero and checking the crossover using the DC gain will follow ...
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... Switch pin. Applying a negative voltage (with respect to the IC's ground) to any monolithic IC pin causes erratic and unpredictable operation of that IC. This holds true for the LM5000 IC as well. When used in a flyback regulator, the voltage at the Switch pin can go negative when can be used the switch turns on. The “ ...
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... Additionally, the RC filter can reduce the dissipation within the device when the input voltage is high. Flyback Regulator Operation The LM5000 is ideally suited for use in the flyback regulator topology. The flyback regulator can produce a single output voltage, or multiple output voltages. ...
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... CRCW120610R0F R 6 CRCW12062003F R 7 CRCW12061002F Q 1 CXT5551-NSA U 1 LM5000-3 www.national.com DESCRIPTION Capacitor, CER, TDK Capacitor, CER, TDK Capacitor, CER, KEMET Capacitor, CER, KEMET Capacitor, CER, KEMET Capacitor, CER, KEMET Capacitor, CER, KEMET Capacitor, CER, TDK Capacitor, CER, TDK Capacitor, CER, KEMET ...
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Physical Dimensions inches (millimeters) unless otherwise noted For Ordering, Refer to Ordering Information Table TSSOP-16 Pin Package (MTC) NS Package Number MTC16 15 www.national.com ...
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LLP-16 Pin Package (SDA) For Ordering, Refer to Ordering Information Table NS Package Number SDA16A 16 ...
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Notes 17 www.national.com ...
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