LT1573I LINER [Linear Technology], LT1573I Datasheet
LT1573I
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LT1573I Summary of contents
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FEATURES Low Cost Solution for High Current, Low Dropout Regulators Fast Transient Response Needs Much Less Bulk Capacitance Latching Overload Protection Minimizes Heat Sink Size Precision Output Voltage (1%) Single Supply Operation 2.8V to 10V IN Small Surface ...
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... GND) .......................... 10V OUT Shutdown Pin Voltage (V to GND) .................. 10V SHDN Operating Junction Temperature Range LT1573C ............................................... 125 C LT1573I ............................................ – 125 C Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec.)................ 300 C ELECTRICAL CHARACTERISTICS range, otherwise specifications are at T PARAMETER DC Characteristics LT1573 Reference Voltage (Adjustable)(Note 2) LT1573-3 ...
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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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U TYPICAL APPLICATIO S FB LATCH + SHDN C TIME 0.5 F GND AVX 100 F/10V SURFACE MOUNT TANTALUM CAPACITOR IN OUT C = 0.5 F FOR 100ms TIME OUT AT ROOM TEMPERATURE ...
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LT1573 U TYPICAL APPLICATIO S High Efficiency 2.5V to 1.8V Converter at 5A Output Current FB LATCH + SHDN C TIME 0.5 F GND V IN2 IN1 OUT C = AVX 15 F/10V SURFACE ...