LTC3813IG#TRPBF Linear Technology, LTC3813IG#TRPBF Datasheet
LTC3813IG#TRPBF
Specifications of LTC3813IG#TRPBF
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LTC3813IG#TRPBF Summary of contents
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... MOSFET Gate Drive + INTV UV CC – INTV LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 5847554, 6304066, 6476589, 6580258, 6677210, 6774611. 50k V IN 10V TO 40V + 10μH 22μ ...
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... TAPE AND REEL LTC3813EG#PBF LTC3813EG#TRPBF LTC3813IG#PBF LTC3813IG#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are 10V – + NDRV SYNC SENSE SENSE SYMBOL PARAMETER V Feedback Voltage FB ΔV Feedback Voltage Line Regulation FB,LINE V Maximum Current Sense ...
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LTC3813 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are 10V – NDRV SYNC SENSE SENSE SYMBOL PARAMETER I PGOOD Leakage Current PGOOD PG Delay PGOOD Delay V Regulators ...
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TYPICAL PERFORMANCE CHARACTERISTICS Load Transient Response V OUT 200mV/ DIV I OUT 2A/DIV 3813 G01 100 μ s/DIV FIGURE 14 CIRCUIT V = 12V LOAD STEP Effi ciency vs Load Current 100 V = 24V OUT ...
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LTC3813 TYPICAL PERFORMANCE CHARACTERISTICS Off-Time vs Temperature 680 I = 300 μ A OFF 660 640 620 600 580 560 –50 – 100 TEMPERATURE (°C) 3813 G10 Feedback Reference Voltage vs Temperature 0.803 0.802 0.801 0.800 ...
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TYPICAL PERFORMANCE CHARACTERISTICS EXTV LDO Resistance at CC Dropout vs Temperature –50 – 100 TEMPERATURE (°C) 3813 G18 INTV Current vs INTV Voltage CC CC 4.0 3.5 3.0 ...
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LTC3813 PIN FUNCTIONS I (Pin 1): Off-Time Current Input. Tie a resistor from OFF V to this pin to set the one-shot timer current and OUT thereby set the switching frequency. V (Pin 4): Off-Time Voltage Input. Voltage trip point ...
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PIN FUNCTIONS BG (Pin 19): Bottom Gate Drive. The BG pin drives the gate of the bottom N-channel main switch MOSFET. This pin swings from BGRTN to DRV . CC BGRTN (Pin 20): Bottom Gate Return. This pin connects to ...
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LTC3813 FUNCTIONAL DIAGRAM UVIN UV1 14 R UV2 SYNC 7 0.8V PLL-SYNC PLL/LPF 10 V OFF VOFF R OFF OFF t = (76pF) OFF I IOFF V 1 OUT + I CMP – 1.4V ...
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OPERATION Main Control Loop The LTC3813 is a current mode controller for DC/DC step- up converters. In normal operation, the top MOSFET is turned on for a fi xed interval determined by a one-shot timer (OST). When the top MOSFET ...
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LTC3813 OPERATION from DRV when the top MOSFET turns off output CC overvoltage condition, where it is possible that the bot- tom MOSFET will be off for an extended period of time, an internal timeout guarantees that the ...
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APPLICATIONS INFORMATION The basic LTC3813 application circuit is shown on the fi rst page of this data sheet. External component selection is primarily determined by the maximum input voltage and load current and begins with the selection of the sense ...
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LTC3813 APPLICATIONS INFORMATION Power MOSFET Selection The LTC3813 requires two external N-channel power MOSFETs, one for the bottom (main) switch and one for the top (synchronous) switch. Important parameters for the power MOSFETs are the breakdown voltage BV threshold voltage ...
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APPLICATIONS INFORMATION increase in coulombs on the horizontal axis from while the curve is fl at) is specifi ed for a given V voltage, but can be adjusted for different V multiplying by the ratio of the ...
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LTC3813 APPLICATIONS INFORMATION Operating Frequency The choice of operating frequency is a tradeoff between effi ciency and component size. Low frequency operation improves effi ciency by reducing MOSFET switching losses but requires larger inductance and/or capacitance in order to maintain ...
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APPLICATIONS INFORMATION With these resistor values, the frequency will remain relatively constant at (Hz) R (76pF) OFF for the range of 0.45V to 1.55 • tional to V outside of this range. IN ...
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LTC3813 APPLICATIONS INFORMATION The required inductance can then be calculated to be: V • D IN(MIN) MAX • The required saturation of the inductor should be chosen to be greater than the peak inductor current: ...
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APPLICATIONS INFORMATION Once the output capacitor ESR and bulk capacitance have been determined, the overall ripple voltage wave- form should be verifi dedicated PC board (see PC Board Layout Checklist section for more information on component placement). ...
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LTC3813 APPLICATIONS INFORMATION Input Voltage Undervoltage Lockout A resistor divider connected from the input supply to the UVIN pin (see Functional Diagram) is used to program the input supply undervoltage lockout thresholds. When the rising voltage at UVIN reaches 0.88V, ...
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APPLICATIONS INFORMATION Using the INTV Regulators CC One, both or neither of these regulators can be used to generate the 10V IC/driver supply depending on the circuit requirements, available supplies, and the voltage range Deriving ...
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LTC3813 APPLICATIONS INFORMATION Power Dissipation Considerations Applications using large MOSFETs and high frequency of operation may result in a large DRV current. Therefore, when using the linear regulators necessary to verify that the resulting power dissipation is within ...
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APPLICATIONS INFORMATION REF 3813 F11 REF 3813 F12 The two types of compensation networks, Type 2 and Type 3 are shown in Figures 11 and 12. ...
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LTC3813 APPLICATIONS INFORMATION the appropriate parasitic values are known, simulated or generated from the modulator transfer function. Mea- surement will give more accurate results, but simulation or transfer function can often get close enough to give a working system. To ...
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APPLICATIONS INFORMATION Finally, choose a convenient resistor value for R1 (10k is usually a good value). Now calculate the remaining values constant, used in the calculations chosen crossover frequency (GAIN/20 (this converts ...
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LTC3813 APPLICATIONS INFORMATION self-consistency between the assumed MOSFET junction temperature and the resulting value of I the MOSFET switches. Caution should be used when setting the current limit based upon the R of the MOSFETs. The maximum DS(ON) current limit ...
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APPLICATIONS INFORMATION If the external frequency ( greater than the oscil- SYNC lator frequency f , current is sourced continuously, pull- O ing up the PLL/LPF pin. When the external frequency is less than f , current is ...
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LTC3813 APPLICATIONS INFORMATION 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 load step occurs, V immediately shifts ...
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APPLICATIONS INFORMATION Verify that the Si7848DP is also a good choice for the bottom MOSFET by checking its power dissipation at current limit and minimum input voltage, assuming a junction temperature of 30°C above a 70°C ambient (ρ = 1.4): ...
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LTC3813 APPLICATIONS INFORMATION PC Board Layout Checklist When laying out a PC board follow one of two suggested approaches. The simple PC board layout requires a dedi- cated ground plane layer. Also, for higher currents recommended to use ...
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... FLASH SHALL NOT EXCEED .254mm (.010") 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Current Mode Synchronous Step-Up Controller LTC3872 No R Current Mode Boost DC/DC Controller SENSE LTC3873 No R Constant-Frequency Boost/Flyback/SEPIC SENSE Controller trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 24V Input Voltage to 50V/5A Synchronized at 250kHz R NDRV ...