ltc1504a Linear Technology Corporation, ltc1504a Datasheet
ltc1504a
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ltc1504a Summary of contents
Page 1
... The LTC1504A is specified to operate with input voltages between 4V and 10V. Contact the LTC factory for guaranteed specifications at 2.7V supply. The LTC1504A is a pin-compatible, functional upgrade to the LTC1504. The LTC1504A is available in a plastic SO-8 package. , LTC and LT are registered trademarks of Linear Technology Corporation. 100 90 L ...
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... Supply Voltage (V to GND) ................................... 10V CC Peak Output Current (SW) ....................................... 1A Input Voltage (All Other Pins) ...... – 0. Operating Temperature Range LTC1504AC ............................................. LTC1504AI ......................................... – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER V ...
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... Ouput Swing COMP CC Note 4: LTC1504A quiescent current is dominated by the gate drive current drawn by the onboard power switches. With FB or SENSE pulled to V the output stage will stop switching and the static quiescent current CC can be observed. With FB or SENSE hooked up normally, the output stage will be switching and total dynamic supply current can be measured ...
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... CC (usually 0.1 F) from SS to GND to limit the output rise time during power-up. C loop, allowing the LTC1504A to enter and exit current limit cleanly. See the Applications Information section for more details. COMP (Pin 8): External Compensation. An external RC network should be connected to COMP to compensate the feedback loop ...
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... OUT L : COILCRAFT D03316-473 EXT Figure APPLICATIONS INFORMATION OVERVIEW The LTC1504A is a complete synchronous switching regulator controller (see Block Diagram). It includes two on-chip 1.3 power MOSFETs, eliminating the need for external power devices and minimizing external parts TO INTERNAL BLOCKS SAW – PWM + I ...
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... Q1 and Q2 are capable of carrying peak currents in excess of 500mA, with the continuous output power level limited primarily by the thermal dissipation of the SO-8 package. With a 5V input and a 3.3V output, the LTC1504A can supply 500mA of continuous output current with an appropriate layout. An on-chip current limit circuit, set with a single external resistor, can be used to help limit power dissipation ...
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... The choice of which style inductor to use often depends more on the price vs size requirements and any radiated field/EMI requirements than on what the LTC1504A requires to operate. Table 2 shows some typical surface mount inductors that work well in LTC1504A applications. LTC1504A ...
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... Open Output Capacitor The output capacitor affects the performance of the LTC1504A in a couple of ways: it provides the first line of defense during a transient load step and it has a large effect on the compensation required to keep the LTC1504A feedback loop stable. Transient load response of an LTC1504A circuit is controlled almost entirely by the output capacitor and the inductor ...
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... Figure 4b. Optimum Compensation Network W U Soft Start and Current Limit Soft start and current limit are linked in the LTC1504A. Soft start works in a straightforward manner. An internal 12 A current source connected to the SS pin will pull up an external capacitor connected from SS to GND at a rate determined by the capacitor value. COMP is clamped to a voltage one diode drop above SS ...
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... Note that the current limit is primarily designed to protect the LTC1504A from damage and is not intended to be used to generate an accurate constant-current output. As the die temperature varies in a current limited condition, the ...
Page 11
... Note that long traces at the SW node may aggravate EMI consider- ations—don’t get carried away Schottky diode is used at the SW node, it should be located at the LTC1504A end of the trace, close to the device pins. The LTC Applications Department has constructed liter- ...
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... Input Range, 95% Efficiency, SO-8 Package SCSI-2 Active Terminator 110 • • • 110 NC 110 I SHDN MAX L EXT 110 4.7 F 110 15k LTC1504A CERAMIC + GND FB C OUT SS COMP 12k NC 7.5k 220pF 0.01 F 1504A • TA04 0.189 – 0.197* (4.801 – 5.004 0.228 – 0.244 (5.791 – ...