LTC1627CS8 Linear Technology, LTC1627CS8 Datasheet
LTC1627CS8
Specifications of LTC1627CS8
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LTC1627CS8 Summary of contents
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... The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode, saving components and board space. The LTC1627 comes in an 8-lead SO package. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation ...
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... Note 3: The LTC1627 is tested in a feedback loop that servos V balance point for the error amplifier (V and power Note 4: Dynamic supply current is higher due to the gate charge being A delivered at the switching frequency ORDER PART TOP VIEW NUMBER 8 SYNC/FCB LTC1627CS8 LTC1627IS8 PART MARKING S8 PACKAGE 8-LEAD PLASTIC SO ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Input Voltage 100 100mA LOAD I = 300mA LOAD 10mA LOAD 2.5V OUT ...
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LTC1627 W U TYPICAL PERFOR A CE CHARACTERISTICS Oscillator Frequency vs Temperature 390 380 SYNC/FCB 370 360 350 340 330 320 310 300 – 50 – 100 125 ...
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CTIO S I (Pin 1): Error Amplifier Compensation Point. The TH current comparator threshold increases with this control voltage. Nominal voltage range for this pin 1.2V. RUN/SS (Pin 2): Combination of Soft-Start ...
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LTC1627 U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC1627 uses a constant frequency, current mode step-down architecture. Both the main and synchronous switches, consisting of top P-channel and bottom N-channel power MOSFETs, are internal. During normal operation, ...
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U OPERATIO load slightly allows constant frequency PWM operation to resume. Frequency synchronization is inhibited when the feedback voltage V is below 0.6V. This prevents the external clock FB from interfering with the frequency foldback for short- circuit protection. Dropout ...
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LTC1627 U U APPLICATIO S I FOR ATIO frequency. The actual reduction in average current is less than for peak current. The basic LTC1627 application circuit is shown in Figure 1. External component selection is driven by the load requirement ...
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U U APPLICATIO S I FOR ATIO The selection driven by the required effective series OUT resistance (ESR). Typically, once the ESR requirement is satisfied, the capacitance is adequate for filtering. The output ripple V is determined ...
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LTC1627 U U APPLICATIO S I FOR ATIO Auxiliary Winding Control Using SYNC/FCB Pin The SYNC/FCB pin can be used as a secondary feedback input to provide a means of regulating a flyback winding output. When this pin drops below ...
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U U APPLICATIO S I FOR ATIO Checking Transient Response The regulator loop response can be checked by looking at the load transient response. Switching regulators take several cycles to respond to a step in load current. When a load ...
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LTC1627 U U APPLICATIO S I FOR ATIO 3. Does the (+) plate of C connect possible? This capacitor provides the AC current to the internal power MOSFETs. 4. Keep the switching node SW away from sensitive ...
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U TYPICAL APPLICATIO S C ITH 47pF ITH 47pF Input to 3.3V/0.5A Regulator * SUMIDA CD54-150 AVX TPSC107M006R0150 SYNC/FCB TH *** AVX TPSC226M016R0375 2 7 RUN/SS ...
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LTC1627 U TYPICAL APPLICATIO S C ITH 47pF 0 SUMIDA CD54-100 ** ZETEX BAT54S † AVX TPSC107M006R0150 †† AVX TPSC226M016R0375 C ITH 47pF 3.3V Input to 2.5V/0.5A ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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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... Pin, Constant Frequency 600mA, REF OUT V from 2.65V to 8.5V IN 16-Pin SO and SSOP 36V, Fault Protection IN 550kHz, 6-Pin SOT-23 5A, OUT V from 2.2V to 10V IN 550kHz, MS8 12V OUT 550kHz, MS8 7V 600mA IN Q OUT 1627fa LT/TP 0600 2K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 to 600mA ...