LT1573CS8 Linear Technology, LT1573CS8 Datasheet
LT1573CS8
Specifications of LT1573CS8
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LT1573CS8 Summary of contents
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... Fixed or Adjustable Outputs Shutdown U APPLICATIO S 3.3V to 2.5V Regulators Microprocessor Power Sources Post Regulator for Switching Supplies High Efficiency Linear Regulators Ultralow Dropout Regulators Low Voltage Linear Regulators , LTC and LT are registered trademarks of Linear Technology Corporation. U TYPICAL APPLICATIO C C 100pF FB COMP LATCH V ...
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... I = 250mA 1.15V DRIVE SHDN U W ORDER PART NUMBER TOP VIEW LT1573CS8 1 8 COMP LT1573CS8-2 OUT LT1573CS8-2 LT1573CS8-3 DRIVE LT1573IS8 S8 PACKAGE S8 PART MARKING 8-LEAD PLASTIC 125 1573 JMAX JA 157325 157328 MIN TYP MAX 1.252 1.265 1.278 1.225 1.265 1.305 3.267 3.3 3.333 < ...
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ELECTRICAL CHARACTERISTICS range, otherwise specifications are PARAMETER LATCH Pin Latch-Off Threshold Voltage LATCH Pin Charging Current LATCH Pin Latching Current V – V Differential Threshold for Latch Disable IN OUT Input Quiescent Current Minimum Input Voltage for ...
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LT1573 W U TYPICAL PERFOR A CE CHARACTERISTICS Drive Pin Current vs Feedback Pin Voltage 450 T = 130 C J 400 350 300 T = – 250 200 150 100 50 0 ...
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CTIO S FB (Pin 1): The feedback pin is the inverting input of the error amplifier. The noninverting input of the error ampli- fier is internally connected to a 1.265V reference. The error amplifier will ...
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LT1573 W BLOCK DIAGRA NORMALLY SHDN 3 OFF C3 – GND 4 V SHDNTH + I I LATCH NORMALLY OFF 2 LATCH S4 + EXTERNAL CAPACITOR LATCHTH – C EXT THERMAL SHUTDOWN U ...
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U U APPLICATIO S I FOR ATIO The LT1573 is designed to be used in conjunction with an external PNP transistor. The overall specifications of a regulator circuit using the LT1573 and an external PNP will be heavily dependent on ...
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LT1573 U U APPLICATIO S I FOR ATIO output current with dropout voltage as low as 0.35V. The gain-bandwidth product f of the D45H11 is typically T 40MHz which enables the regulator, composed of this PNP transistor and the LT1573, ...
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U U APPLICATIO S I FOR ATIO Resistor R helps to turn off the PNP (Q B Smaller values for R turn off the PNP faster but will B increase input current. The recommended value for For ...
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LT1573 U U APPLICATIO S I FOR ATIO Thermal Considerations The thermal characteristics of several components need to be considered; the LT1573, the pass transistor and resistor R . Power dissipation should be calculated based D on the worst-case conditions ...
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U U APPLICATIO S I FOR ATIO capabilities of the PC board and its copper traces. Table 3 lists some typical values for the thermal resistance of the LT1573. Measured values of thermal resistance for a specific board size with ...
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LT1573 U U APPLICATIO S I FOR ATIO needed during output transients, more capacitance can be added to the regulator output. If more capacitance is added to the output, the bandwidth of the regulator is lowered. A large value compensation ...
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U U APPLICATIO S I FOR ATIO equals the resistance ..., and and the resistance R equals the resistance and R in parallel. Dn Voltage Feedback Resistor Divider Table ...
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LT1573 U TYPICAL APPLICATIO S FB LATCH + SHDN C TIME 0.5 F GND SURFACE MOUNT TANTALUM CAPACITOR SURFACE MOUNT CERAMIC CAPACITOR OUT1 SURFACE ...
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... SHDN (ACTIVE HIGH) PIN SHOULD BE TIED TO GROUND NOT USED Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... LOAD R2 1k 1/8W GND 1573 TA06 0.189 – 0.197* (4.801 – 5.004 0.150 – 0.157** 0.228 – 0.244 (3.810 – 3.988) (5.791 – 6.197) SO8 1298 Noise RMS 1573fa LT/TP 1299 2K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1997 ...