LM26001EM NSC [National Semiconductor], LM26001EM Datasheet
LM26001EM
Related parts for LM26001EM
LM26001EM Summary of contents
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LM26001 1.5A Switching Regulator with High Efficiency Sleep Mode General Description The LM26001 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 efficiency under light-load ...
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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 20179402 Top View 16-Lead Plastic TSSOP Package Drawing Package Marking MXA16A LM26001EM MXA16A LM26001EM Description 2 Supplied As 92 Units of Rail 2500 Units of 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 -0.3V to 40V SW (Note 7) -0.5V to 40V VDD -0.3V ...
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Electrical Characteristics apply over the junction temperature (T Maximum limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric norm 25˚C, and are provided for reference purposes only. (Note 5) (Continued) ...
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Typical Performance Characteristics = 12V 25˚C. J VFB vs Temperature IQ and IVBIAS vs Temperature (Sleep Mode) Normalized Switching Frequency vs Temperature (300kHz) Unless otherwise specified the following conditions apply: Vin 20179403 IQ and IVBIAS vs Temperature (PWM ...
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Typical Performance Characteristics 12V 25˚C. (Continued) J Peak Current Limit vs Temperature Efficiency vs Load Current (330kHz) Startup Waveforms www.national.com Unless otherwise specified the following conditions apply: Vin = Short Circuit Foldback Frequency vs V 20179415 Efficiency vs ...
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Block Diagram Operation Description GENERAL The LM26001 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 inductor current is internally ...
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Operation Description the reset threshold, at which point switching resumes. This 1% FB window limits the corresponding output ripple to approximately 1% of nominal output voltage. The sleep cycle will repeat until load current is increased. Figure 2 shows typical ...
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Operation Description on, enable, or UVLO recovery, an internal 2.3 µA (typical) current charges the soft-start capacitor. During soft-start, the error amplifier output voltage is controlled by both the soft- start voltage and the feedback loop. As the SS pin ...
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Operation Description Where fnom is the nominal switching frequency set by the FREQ resistor, and fsync is a square wave. If the SYNC pin is not used, it must be pulled low for normal operation. A 10kΩ pull-down resistor is ...
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Design Information (Continued) SETTING OUTPUT VOLTAGE The output voltage is set by the ratio of a voltage divider at the FB pin as shown in the typical application. The resistor values can be determined by the following equation: Where Vfb ...
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Design Information (Continued) Re can also be calculated from the following equation: Where ∆Vt is the allowed voltage excursion during a load transient, and ∆It is the maximum expected load transient. If the total ESR is too high, the load ...
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Design Information (Continued) FIGURE 8. Control-Output Transfer Function The control-output transfer function consists of one pole (fp), one zero (fz), and a double pole at fn (half the switching frequency). Referring to Figure 8, the following should be done to ...
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Design Information (Continued second pole (fpc1) can also be placed at fz. This pole can be created with a single capacitor, C9. The minimum value for this capacitor can be calculated by: C9 may not be necessary in ...
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Thermal Considerations and TSD (Continued) 2 Psw = D x Iload x (0.2 + 0.00065 Vin x 4 Vin Vbias x I VBIAS VBIAS ...
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Physical Dimensions inches (millimeters) unless otherwise noted National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and ...