LM26001BMH NSC [National Semiconductor], LM26001BMH Datasheet
LM26001BMH
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LM26001BMH Summary of contents
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LM26001B 1.5A Switching Regulator with High Efficiency Sleep Mode General Description The LM26001B 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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... Connection Diagram Ordering Information Order Number Package Type LM26001BMH TSSOP-16EXP LM26001BMHX TSSOP-16EXP Pin Descriptions Pin # Pin Name 1 VIN Power supply input 2 VIN Power supply input 3 PGOOD Power Good pin. An open drain output which goes high when the output voltage is greater than 92% of nominal ...
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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 20V SW (Note 7) -0.5V to 20V VDD -0.3V ...
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Symbol Parameter F Lower frequency synchronization SYNC_DN range 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 ...
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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 = (IDC = 300 mA) 30001903 IQ and ...
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Peak Current Limit vs Temperature Efficiency vs Load Current (330kHz) Startup Waveforms www.national.com Short Circuit Foldback Frequency vs V 30001915 Efficiency vs Load Current (500kHz) 30001908 Load Transient Response 30001910 6 FB (325 kHz nominal) 30001912 30001909 30001952 ...
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Low Input Voltage Dropout Nominal VOUT = 5V 30001953 7 www.national.com ...
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Block Diagram www.national.com 8 30001918 ...
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Operation Description GENERAL The LM26001B 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 ...
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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 positive current always flows in the inductor. Typical discontinuous operation ...
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FREQUENCY ADJUSTMENT AND SYNCHRONIZATION The switching frequency of the LM26001B can be adjusted between 150 kHz and 500 kHz using a single external resis- tor. This resistor is connected from the FREQ pin to ground as shown in the typical ...
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VIN, it will not discharge through VIN. Therefore when the VIN voltage drops rapidly, VDD may remain high, especially in sleep mode. For fast line voltage transients, using a larger capacitor at the VDD pin ...
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For example maximum load of 1.5A and a ripple content of 33%, peak inductor current is equal to 1.75A which is safely below the minimum current limit of 1.80A. By increasing the inductor size, ripple content and peak ...
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COMPENSATION The purpose of loop compensation is to ensure stable oper- ation while maximizing dynamic performance. Stability can be analyzed with loop gain measurements, while dynamic per- formance is analyzed with both loop gain and load transient response. Loop gain ...
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Where B is the desired feedback gain in v/v between fp and fz, and gm is the transconductance of the error amplifier. A gain value around 10dB (3.3v/v) is generally a good starting point. Bandwidth increases with increasing values of ...
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Thermal Considerations and TSD Although the LM26001B has a built in current limit, at ambient temperatures above 80°C, device temperature rise may limit the actual maximum load current. Therefore, temperature rise must be taken into consideration to determine the maximum ...
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Physical Dimensions inches (millimeters) unless otherwise noted eTSSOP-16 Package 16-Lead Exposed Pad TSSOP Package NS Package Number MXA16A 17 www.national.com ...
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