LTC3720EGN Linear Technology, LTC3720EGN Datasheet
LTC3720EGN
Specifications of LTC3720EGN
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LTC3720EGN Summary of contents
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... The regulator current limit level is also user programmable. Wide supply range allows operation from 4V to 36V at the input. , LTC and LT are registered trademarks of Linear Technology Corporation trademark of Linear Technology Corporation. SENSE Pentium is a registered trademark of Intel Corporation. ...
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... CC CC TG, BG, INTV , EXTV RMS Currents .............. 50mA CC CC Operating Ambient Temperature Range LTC3720EGN (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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... 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 LTC3720EGN • Note 4: The LTC3720 is tested in a feedback loop that adjusts V a specified error amplifier output voltage (I ) ...
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LTC3720 W U TYPICAL PERFOR A CE CHARACTERISTICS Current Sense Threshold vs I Voltage TH 300 RNG 200 1.4V 1V 0.7V 100 0.5V 0 –100 –200 0 1.0 1.5 2.0 2.5 3.0 0.5 I VOLTAGE (V) TH ...
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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) 3720 G10 EXTV Switch Resistance CC vs Temperature 10 8 ...
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LTC3720 W U TYPICAL PERFOR A CE CHARACTERISTICS Transient Response (Forced Continuous Mode) V OUT 50mV/DIV I L 10A/DIV 20 s/DIV LOAD STEP = 0A TO 15A V = 15V 1.5V OUT FCB = 0V FIGURE 7 ...
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CTIO S V (Pin 18): Power Supply Voltage for VID. Range is from CC 3.1V to 5.5V. EXTV (Pin 19): External V Input. When EXTV CC CC ceeds 4.7V, an internal switch connects this pin ...
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LTC3720 CTIO AL DIAGRA 0.7V 2.4V 1 OST V VON t = (10pF ION S 20k + + I CMP – – 1.4V V RNG 4 ...
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U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC3720 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 ...
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LTC3720 U U APPLICATIO S I FOR ATIO The basic LTC3720 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 – JUNCTION TEMPERATURE ( C) Figure 2. R vs. Temperature DS(ON) the load current. When the LTC3720 is operating in continuous mode, the duty cycles ...
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LTC3720 U U APPLICATIO S I FOR ATIO R VON1 30k V OUT C VON R VON2 0.01 F 100k (3a) Figure 3. Correcting Frequency Shift with Load Current Changes shown in Figure 3a. Place capacitance ...
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U U APPLICATIO S I FOR ATIO This formula has a maximum This simple worst-case condition is RMS OUT(MAX) commonly used for design because even significant deviations do not offer much relief. Note ...
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LTC3720 U U APPLICATIO S I FOR ATIO + OPTIONAL LTC3720 EXTV CC EXTV SW CC CONNECTION 5V < V < SEC + FCB SENSE R3 BG SGND PGND Figure 4. Secondary Output Loop and ...
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... I 0 1.200V The junction temperature can be estimated from the 1 1.225V equations given in Note 3 of the Electrical Characteristics. 0 1.150V For example, the LTC3720EGN is limited to less than 1 1.175V 19mA from a 30V supply: 0 1.100V (19mA)(30V)(95 C/W) = 125 1.125V For larger currents, consider using an external supply with 0 1 ...
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LTC3720 U U APPLICATIO S I FOR ATIO External Gate Drive Buffers The LTC3720 drivers are adequate for driving up to about 60nC into MOSFET switches with RMS currents of 50mA. Applications with larger MOSFET switches or operating at higher ...
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U U APPLICATIO S I FOR ATIO operation can prove annoying during troubleshooting. The feature can be overridden by adding a pull-up current greater than the RUN/SS pin. The additional current prevents the discharge of C also ...
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LTC3720 U U APPLICATIO S I FOR ATIO Design Example As a design example, take a supply with the following specifications 24V (15V nominal 1.825V with typical at 1.5V, I OUT(MAX) First, calculate ...
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U U APPLICATIO S I FOR ATIO However 15A load step will cause an output change (ESR) = (15A) (0.005 ) = 75mV OUT(STEP) LOAD The complete circuit is shown in ...
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LTC3720 U U APPLICATIO S I FOR ATIO By positioning the output voltage 60mV above the regula- tion point at no load, it will only drop 65mV below the regulation point after the load step, well within the 100mV tolerance. ...
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... Figure 8. 15A CPU Core Voltage Regulator with Active Voltage Positioning at 300kHz V OUT 100mV/DIV 1. 10A/DIV 270 F 20 s/DIV OUT V = 15V IN FIGURE 7 CIRCUIT Figure 9. Normal Transient Response ( positioning accomplishes this with only three output ca- pacitors rather than five. Refer to Linear Technology Design Solutions 10 for additional information about active voltage positioning 0. RUN/SS BOOST ...
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LTC3720 U U APPLICATIO S I FOR ATIO PC Board Layout Checklist When laying out the printed circuit board, use the follow- ing checklist to ensure proper operation of the controller. These items are also illustrated in Figure 11. • ...
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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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... Dual, 550kHz, 2-Phase Synchronous Step-Down Controllers LTC3728/LTC3728L LTC3730/LTC3732 3-Phase Synchronous DC/DC Step-Down Controllers LTC3831 DDR Memory Termination Power Supply Burst Mode is registered trademark of Linear Technology Corporation. Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 COMMENTS Power Good Output, Minimum Input/Output Capacitors, 3 ...