LTC3711EGN Linear Technology, LTC3711EGN Datasheet
LTC3711EGN
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LTC3711EGN Summary of contents
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... Soft-start capability for sup- ply sequencing is accomplished using an external timing capacitor. The regulator current limit level is user pro- grammable. Wide supply range allows operation from 4V to 36V at the input. , LTC and LT are registered trademarks of Linear Technology Corporation. ® Processors trademark of Linear Technology Corporation. ...
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... CC CC TG, BG, INTV , EXTV RMS Currents .............. 50mA CC CC Operating Ambient Temperature Range LTC3711EGN (Note 2) ........................ – Junction Temperature (Note 3) ............................ 125 C Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are T SYMBOL PARAMETER Main Control Loop ...
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... Note 2: The LTC3711E is guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls. Note calculated from the ambient temperature T J dissipation P as follows: D LTC3711EGN • 130 C/ The denotes specifications which apply over the full operating = 15V unless otherwise noted ...
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LTC3711 W U TYPICAL PERFOR A CE CHARACTERISTICS Transient Response V OUT 50mV/DIV I L 10A/DIV 20 s/DIV 3711 G01 LOAD STEP = 0A TO 15A V = 15V 1.5V OUT FCB = 0V FIGURE 9 CIRCUIT ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS On-Time vs I Current ON 10k VON 1k 100 100 I CURRENT ( A) ON 3711 G11 Current Limit Foldback 150 RNG 125 100 ...
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LTC3711 W U TYPICAL PERFOR A CE CHARACTERISTICS Error Amplifier g vs Temperature m 2.0 1.8 1.6 1.4 1.2 1.0 –50 – 100 125 TEMPERATURE ( C) 3711 G19 EXTV Switch Resistance CC vs Temperature 10 ...
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CTIO S VID0-VID4 (Pins 23, 24, 1, 12, 13): VID Digital Inputs. The voltage identification (VID) code sets the internal feedback resistor divider ratio for different output voltages as shown in Table 1. If unconnected, ...
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LTC3711 CTIO AL DIAGRA 0.7V 2.4V 1 OST V VON t = (10pF ION 20k + I CMP – 1.4V V RNG 5 0.7V 3 ...
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U OPERATIO Main Control Loop The LTC3711 is a current mode controller for DC/DC step-down converters. In normal operation, the top MOSFET is turned on for a fixed interval determined by a one-shot timer OST. When the top MOSFET is ...
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LTC3711 U U APPLICATIO S I FOR ATIO The basic LTC3711 application circuit is shown in Figure 1. External component selection is primarily de- termined by the maximum load current and begins with the selection of the sense resistance and ...
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U U APPLICATIO S I FOR ATIO 2.0 1.5 1.0 0.5 0 – JUNCTION TEMPERATURE ( C) Figure 2. R vs. Temperature DS(ON) The resulting power dissipation in the MOSFETs at maxi- mum output current are: 2 ...
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LTC3711 U U APPLICATIO S I FOR ATIO R VON1 30k V OUT C VON R VON2 0.01 F 100k (4a) Figure 4. Correcting Frequency Shift with Load Current Changes as current increases, constant frequency operation ...
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U U APPLICATIO S I FOR ATIO V V OUT OUT MAX ( ) IN MAX ( ) Once the value for L is known, the type of inductor must be selected. High efficiency ...
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LTC3711 U U APPLICATIO S I FOR ATIO to approximately V + INTV . The boost capacitor needs store about 100 times the gate charge required by the top MOSFET. In most applications a 0 ...
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U U APPLICATIO S I FOR ATIO Output Voltage Programming The output voltage is digitally set to levels between 0.900V and 2.000V using the voltage identification (VID) inputs VID0-VID4. An internal 5-bit DAC configured as a preci- sion resistive voltage ...
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LTC3711 U U APPLICATIO S I FOR ATIO EXTV Connection CC The EXTV pin can be used to provide MOSFET gate drive CC and control power from the output or another external source during normal operation. Whenever the EXTV pin ...
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U U APPLICATIO S I FOR ATIO current, but requires a diode to isolate C network must be able to pull RUN/SS above the 4.2V maximum threshold of the latchoff circuit and overcome the 4 A maximum discharge current. Efficiency ...
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LTC3711 U U APPLICATIO S I FOR ATIO Figure 9 will provide adequate compensation for most applications. For a detailed explanation of switching control loop theory see Application Note 76. Design Example As a design example, take a supply with ...
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U U APPLICATIO S I FOR ATIO In the design example, Figure 9, five 0.025 capacitors are required in parallel to keep the output voltage within tolerance. Using active voltage positioning, the same specification can be met with only three ...
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LTC3711 U U APPLICATIO S I FOR ATIO The corresponding change in the output voltage is deter- mined by the gain of the error amplifier and feedback divider. The LTC3711 error amplifier has a transconduc- tance g that is constant ...
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U U APPLICATIO S I FOR ATIO 0 RNG1 RNG2 PG 4.99k 45.3k 100k VP2 40. VP1 C1 12.4k 180pF 100pF ...
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LTC3711 U U APPLICATIO S I FOR ATIO V OUT 100mV/DIV I L 10A/DIV 270 F 20 s/DIV OUT V = 15V IN FIGURE 7 CIRCUIT Figure 11. Normal Transient Response ...
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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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... LTC3714 Intel and Transmeta Compatible DC/DC Controller with V20 and Internal Op Amp LTC3732 3-Phase, VRM 9.0/9.1 Synchronous Step-Down Controller Burst Mode is a registered trademark of Linear Technology Corporation. Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 1.5V/15A All Ceramic C ...