LM26003MH NSC [National Semiconductor], LM26003MH Datasheet
LM26003MH
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LM26003MH Summary of contents
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LM26003 3A Switching Regulator with High Efficiency Sleep Mode General Description The LM26003 is a switching regulator designed for the high efficiency requirements of applications with stand-by modes. The device features a low-current sleep mode to maintain ef- ficiency under ...
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... SW Switch pin. The source of the internal N-channel switch Exposed Pad thermal connection. Connect to GND. www.national.com Top View 20-Lead Exposed Pad TSSOP Package Package Drawing Package Marking MXA20A LM26003MH LM26003MH 2 30067602 Supplied As 73 Units in Rail 2500 Units in Tape and Reel ...
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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. Voltages from the indicated pins to GND: VIN SW (Note 7) VDD VBIAS FB BOOT V PGOOD FREQ SYNC ...
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Symbol Parameter T Minimum Off-time OFFMIN T Minimum On-time ONMIN TH Sleep Mode Threshold Hysteresis SLEEP_HYS TH Wake Up Threshold WAKE I BOOT Pin Leakage Current BOOT Protection I Peak Current Limit LIMPK V Short Circuit Frequency Foldback FB_SC Threshold ...
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Typical Performance Characteristics 12V 25°C. J Efficiency vs Load Current (300 kHz) VFB vs Temperature IQ and IVBIAS vs Temperature (Sleep Mode) Unless otherwise specified the following conditions apply: Vin = Efficiency vs Load Current (500 kHz) 30067637 ...
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Startup Waveforms Load Transient Response UVLO Threshold vs Temperature (VDD = VIN) www.national.com Peak Current Limit vs Temperature 30067647 Normalized Switching Frequency vs Temperature (300kHz) 30067646 30067645 6 30067641 30067643 ...
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Block Diagram 7 30067603 www.national.com ...
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Operation Description GENERAL The LM26003 is a current mode PWM buck regulator. At the beginning of each clock cycle, the internal high-side switch turns on, allowing current to ramp-up in the inductor. The in- ductor current is internally monitored during ...
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Until the next cycle, the inductor current remains at zero. At nominal load currents, in FPWM mode, the device operates in continuous conduction mode, where ...
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Second, the inductor value can be increased to slow the current ramp and reduce the peak over-current. FREQUENCY ADJUSTMENT AND SYNCHRONIZATION The switching frequency of the LM26003 can ...
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FIGURE 6. Off-Pulse Skipping Waveforms Vin = 3.5V, Vnom = 3.3V, fnom = 305 kHz UVLO is sensed at both VIN and VDD, and is activated when either voltage falls below 2.96V (typical). Although VDD is typically less than 200 ...
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INDUCTOR The output inductor should be selected based on inductor ripple current. The amount of inductor ripple current com- pared to load current, or ripple content, is defined as Iripple/ Iload. Ripple content should be less than 40%. Inductor ripple ...
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BOOTSTRAP The drive voltage for the internal switch is supplied via the BOOT pin. This pin must be connected to a ceramic capacitor, Cboot, from the switch node, shown the typical ap- plication. The LM26003 provides the ...
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Where Co is the output capacitance the load resistance the output capacitor ESR, and fsw is the switching fre- quency. The effects of slope compensation and current sense gain are included in this equation. However, the ...
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A ceramic input capacitor must be connected as close as possible to the AVIN pin as well as PVIN pin. The capacitor between AVIN and ground should be grounded close to the GND pins of the LM26003 and the PVIN ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted eTSSOP-20 Package 20-Lead Exposed Pad TSSOP Package NS Package Number MXA20A 16 ...
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Notes 17 www.national.com ...
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