LTC3814IFE-5#TRPBF Linear Technology, LTC3814IFE-5#TRPBF Datasheet
LTC3814IFE-5#TRPBF
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LTC3814IFE-5#TRPBF Summary of contents
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... turned off reducing the supply current to <230μA. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and trademark 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 ...
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... TAPE AND REEL LTC3814EFE-5#PBF LTC3814EFE-5#TRPBF LTC3814IFE-5#PBF LTC3814IFE-5#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: ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T otherwise specifi ed. SYMBOL PARAMETER Main Control Loop INTV INTV Supply Voltage INTV Supply Current Q CC INTV Shutdown Current CC I BOOST Supply Current BOOST V ...
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LTC3814-5 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T otherwise specifi ed. SYMBOL PARAMETER PG Delay PGOOD Delay V Regulators CC V EXTV Switchover Voltage EXTVCC CC EXTV Rising CC EXTV Hysteresis CC V INTV Voltage from EXTV ...
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TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current 100 V = 50V OUT V = 36V 24V 12V LOAD (A) 38145 G04 I Voltage ...
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LTC3814-5 TYPICAL PERFORMANCE CHARACTERISTICS Reference Voltage vs Temperature 0.803 0.802 0.801 0.800 0.799 0.798 0.797 –50 – 100 TEMPERATURE (°C) 38145 G14 Driver Peak Source Current vs Supply Voltage 3.0 2.5 2.0 1.5 1.0 0.5 0 ...
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TYPICAL PERFORMANCE CHARACTERISTICS INTV Current vs INTV CC 3.5 3.0 2.5 2.0 1.5 1.0 0 INTV VOLTAGE (V) CC RUN/SS Pull-Up Current vs Temperature 3 RUN/ –50 – ...
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LTC3814-5 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 2): Off-Time Voltage Input. Voltage trip point ...
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FUNCTIONAL DIAGRAM INTV CC 5V REG OFF 2 I OFF R OFF V VOFF (76pF) OUT OFF I IOFF 20k + I CMP – × 1.4V V RNG 3 0. ...
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LTC3814-5 OPERATION Main Control Loop The LTC3814 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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OPERATION IC/Driver Supply Power The LTC3814-5’s internal control circuitry and top and bot- tom MOSFET drivers operate from a supply voltage (INTV pin) in the range of 4.5V to 14V. If the input supply voltage or another available supply is ...
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LTC3814-5 APPLICATIONS INFORMATION Power MOSFET Selection The LTC3814-5 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 When the controller is operating in continuous mode the duty cycles for the top and bottom MOSFETs are given by: V Main Switch Duty Cycle = OUT V OUT Synchronous Switch Duty Cycle = The power dissipation for ...
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LTC3814-5 APPLICATIONS INFORMATION voltage changes, tie the V pin to a resistive divider from OFF shown in Figure 5. Choose the resistor values so IN that the V voltage equals about 1.55V at the mid-point RNG of ...
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APPLICATIONS INFORMATION Minimum On-Time and Dropout Operation The minimum on-time t is the smallest amount of ON(MIN) time that the LTC3814-5 is capable of turning on the bottom MOSFET, tripping the current comparator and turning the MOSFET back off. This ...
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LTC3814-5 APPLICATIONS INFORMATION For many designs it is possible to choose a single capacitor type that satisfi es both the ESR and bulk C requirements for the design. In certain demanding applications, however, the ripple voltage can be improved signifi ...
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APPLICATIONS INFORMATION Input Capacitor Selection The input capacitor of a boost converter is less critical than the output capacitor, due to the fact that the inductor is in series with the input and the input current waveform is continuous (see ...
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LTC3814-5 APPLICATIONS INFORMATION Using the INTV Regulators CC One, both or neither of these regulators can be used to generate the 5.5V IC/driver supply depending on the circuit requirements, available supplies, and the voltage range ...
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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 the ...
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LTC3814-5 APPLICATIONS INFORMATION The two types of compensation networks, Type 2 and Type 3 are shown in Figures 11 and 12. When component values are chosen properly, these networks provide a “phase bump” at the crossover frequency. Type 2 uses ...
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APPLICATIONS INFORMATION If breadboard measurement is not practical, mathemat- ical software such as MATHCAD or MATLAB can be used to generate plots from the transfer function given in Equation 1. A SPICE simulation can also be used to gener- ate ...
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LTC3814-5 APPLICATIONS INFORMATION TYPE 2 Loop: BOOST K = tan + 45° • f • G • K • C1 • f • C1 ...
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APPLICATIONS INFORMATION A reasonable assumption is that the minimum R lies the same percentage below the typical value as the maximum lies above it. Consult the MOSFET manufacturer for further guidelines. Note that in a boost mode architecture ...
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LTC3814-5 APPLICATIONS INFORMATION about 3mA and driver current can be calculated by f where Q GATE G(TOP) G(BOT) are the gate charges of the top and bottom MOSFETs. This loss is proportional to the supply ...
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APPLICATIONS INFORMATION To guarantee proper current limit at worst-case conditions, increase nominal V by 50% to 190mV. To check if the SNS current limit is acceptable at V SNS junction temperature of about 30°C above a 70°C ambient (ρ = ...
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LTC3814-5 APPLICATIONS INFORMATION V OUT R OFF 403k C OFF 100pF 133k 20k PGOOD C SS 1000pF C C2 470pF FB2 250k 47pF BAS19 16 1 BOOST I OFF C B ...
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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 a ...
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LTC3814-5 PACKAGE DESCRIPTION (.108) 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. ...
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... Updated Equations Updated Related Parts 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. LTC3814-5 ...
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... PGND 38145 TA02 up to 60V, Fixed Operating Frequency 50kHz to OUT up to 60V, 50kHz to 900kHz, SSOP-28, OUT up to 60V, 50kHz to 900kHz, SSOP-28 OUT ≤ 36V, Burst Mode Operation IN LT 0111 REV C • PRINTED IN USA © LINEAR TECHNOLOGY CORPORA TION 2007 38145fc ...