LTC3834IUFD#PBF Linear Technology, LTC3834IUFD#PBF Datasheet
LTC3834IUFD#PBF
Specifications of LTC3834IUFD#PBF
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LTC3834IUFD#PBF Summary of contents
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FEATURES n Wide Output Voltage Range: 0.8V ≤ Low Operating Quiescent Current: 30μA ® n OPTI-LOOP Compensation Minimizes C ±1% Output Voltage Accuracy n n Wide V Range 36V IN n Phase-Lockable Fixed Frequency 140kHz to ...
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... LTC3834IFE#PBF LTC3834IFE#TRPBF LTC3834EUFD#PBF LTC3834EUFD#TRPBF LTC3834IUFD#PBF LTC3834IUFD#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. 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 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Main Control Loops V Regulated Feedback Voltage FB I Feedback Current VFB V Reference Voltage Line Regulation REFLNREG V Output Voltage Load Regulation LOADREG g Transconductance Amplifi er ...
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LTC3834 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER PGOOD Output V PGOOD Voltage Low PGL I PGOOD Leakage Current PGOOD V PGOOD Trip Level PG Note 1: Stresses beyond those listed under Absolute Maximum Ratings ...
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TYPICAL PERFORMANCE CHARACTERISTICS Load Step (Burst Mode Operation) V OUT 100mV/DIV AC COUPLED I L 2A/DIV 20μs/DIV 3834 G04 V = 3.3V OUT FIGURE 11 CIRCUIT Inductor Current at Light Load FORCED CONTINUOUS MODE 2A/DIV Burst Mode OPERATION PULSE SKIPPING ...
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LTC3834 TYPICAL PERFORMANCE CHARACTERISTICS Maximum Current Sense Voltage vs I Voltage Cycle TH 100 FORCED CONTINUOUS Burst Mode OPERATION 80 (RISING) Burst Mode OPERATION 6O (FALLING) PULSE SKIPPING –20 10% DUTY CYCLE –40 0 0.2 0.4 0.6 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Regulated Feedback Voltage vs Temperature 808 806 804 802 800 798 796 794 792 30 –45 –30 – TEMPERATURE (°C) 3834 G21 Oscillator Frequency vs Temperature 800 700 600 V PLLLPF 500 ...
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LTC3834 PIN FUNCTIONS (FE/UFD) CLKOUT (Pin 1/Pin 19): Open-Drain Output Clock Signal available to daisy-chain other controller ICs for additional MOSFET driver stages/phases. PLLLPF (Pin 2/Pin 20): The phase-locked loop’s lowpass fi lter is tied to this pin when synchronizing ...
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PIN FUNCTIONS (FE/UFD) operation. Tying this pin to a voltage greater than 0.9V and less than INTV selects pulse-skipping operation. CC PHASMD (Pin 20/Pin 18): Control Input to Phase Selector which determines the phase relationships between TG and the CLKOUT ...
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LTC3834 OPERATION (Refer to Functional Diagram) Main Control Loop The LTC3834 uses a constant-frequency, current mode step-down architecture. During normal operation, the external top MOSFET is turned on when the clock sets the RS latch, and is turned off when ...
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OPERATION (Refer to Functional Diagram) When the RUN pin is pulled low to disable the LTC3834, or when V drops below its undervoltage lockout threshold IN of 3.7V, the TRACK/SS pin is pulled low by an internal MOSFET. When in ...
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LTC3834 OPERATION Frequency Selection and Phase-Locked Loop (PLLLPF and PLLIN/MODE Pins) The selection of switching frequency is a trade-off between effi ciency and component size. Low frequency opera- tion increases effi ciency by reducing MOSFET switching losses, but requires larger ...
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APPLICATIONS INFORMATION R Selection For Output Current SENSE R is chosen based on the required output current. SENSE The current comparator has a maximum threshold of 100mV/R and an input common mode range of SENSE SGND to 10V. The current ...
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LTC3834 APPLICATIONS INFORMATION exceeded. This results in an abrupt increase in inductor ripple current and consequent output voltage ripple. Do not allow the core to saturate! Power MOSFET and Schottky Diode (Optional) Selection Two external power MOSFETs must be selected ...
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APPLICATIONS INFORMATION C and C Selection IN OUT In continuous mode, the source current of the top MOSFET is a square wave of duty cycle (V OUT large voltage transients, a low ESR capacitor sized for the maximum RMS current ...
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LTC3834 APPLICATIONS INFORMATION Tracking and Soft-Start (TRACK/SS Pin) The start- controlled by the voltage on the OUT TRACK/SS pin. When the voltage on the TRACK/SS pin is less than the internal 0.8V reference, the LTC3834 regulates the ...
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APPLICATIONS INFORMATION INTV Regulators CC The LTC3834 features two separate internal P-channel low dropout linear regulators (LDO) that supply power at the INTV pin from either the V supply pin or the EXTV CC IN pin, respectively, depending on the ...
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LTC3834 APPLICATIONS INFORMATION Topside MOSFET Driver Supply (C External bootstrap capacitors connected to the BOOST B pins supply the gate drive voltages for the topside MOSFET. Capacitor C in the Functional Diagram is charged though B external diode ...
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APPLICATIONS INFORMATION Phase-Locked Loop and Frequency Synchronization The LTC3834 has a phase-locked loop (PLL) comprised of an internal voltage-controlled oscillator (VCO) and a phase detector. This allows the turn-on of the top MOSFET (TG locked to the rising ...
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LTC3834 APPLICATIONS INFORMATION Table 2 summarizes the different states in which the PLLLPF pin can be used. Table 2 PLLLPF PIN PLLIN/MODE PIN 0V DC Voltage Floating DC Voltage INTV DC Voltage CC RC Loop Filter Clock Signal Phase-Locked to ...
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APPLICATIONS INFORMATION a 5V output 20% loss for a 3.3V output. Effi ciency varies as the inverse square of V same external components and output power level. The combined effects of increasingly lower output voltages and ...
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LTC3834 APPLICATIONS INFORMATION sudden step change in output voltage if the load switch resistance is low and it is driven quickly. If the ratio greater than 1:50, the switch rise time LOAD OUT should be ...
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APPLICATIONS INFORMATION PC Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the IC. These items are also illustrated graphically in the layout diagram of Figure 9. The ...
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LTC3834 APPLICATIONS INFORMATION high current output loading at lower input voltages, look for inductive coupling between CIN, Schottky and the top MOSFET components to the sensitive current and voltage sensing traces. In addition, investigate common ground path voltage pickup between ...
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TYPICAL APPLICATIONS INTV CC 100k 100k 0.01μF 560pF 100pF 105k 39.2k 432k 22pF M1, M2: Si4840DY L1: CDEP105-7R2M C : SANYO 10TPD150M OUT 0.01μF 1000pF 100pF 48.7k 68.1k 84.5k 100pF M1, M2: Si4840DY L1: TOKO DS3LC A915AY-3R3M High Effi ciency ...
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LTC3834 TYPICAL APPLICATIONS 0.01μF 560pF 150pF 54k 69.8k 365k 39pF M1, M2: Si4840DY L1: CDEP105-3R2M C : SANYO 10TPD150M OUT INTV CC GND 10k 0.01μF 2.2nF 100pF 26.1k 68.1k 34k 390pF M1, M2: Si4840DY L1: CDEP105-2R2M C : SANYO 10TPD150M ...
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... MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY 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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... High Voltage Current Mode Controller with Programmable Operating Frequency LTC3845 Low I Synchronous Step-Down Controller Q LTC3850 Dual, 2-Phase Synchronous Step-Down DC/DC Controller trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● CLKOUT ...