LTC3721-2 LINER [Linear Technology], LTC3721-2 Datasheet
LTC3721-2
Related parts for LTC3721-2
LTC3721-2 Summary of contents
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FeaTures N-Channel Synchronous Rectifier MOSFET Driver n Programmable Timeout Protection n Reverse Inductor Current Protection n Pulse Transformer Synchronization n Wide V Supply Range: 4.5V to 11V n CC 15ns Rise/Fall Times 5V Undervoltage ...
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LTC3900 absoluTe MaxiMuM raTings (Note 1) Supply Voltage V ........................................................................12V CC Input Voltage – TIMER .............................. – 0. SYNC ...................................................... –12V to 12V Input Current + CS ....................................................................15mA Operating Junction Temperature Range (Note 2) LTC3900E ........................................... ...
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T SYMBOL PARAMETER t Timer Discharge Time TMRDIS V Timer Pin Clamp Voltage TMRMAX Current Sense + Input Current CS – I – CS Input Current CS + ...
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LTC3900 Typical perForMance characTerisTics Timeout 5. 25° 51k TMR C = 470pF TMR 5.15 5.10 5.05 5.00 4.95 4.90 4.85 4.80 4. (V) ...
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Typical perForMance characTerisTics Propagation Delay vs C LOAD 120 T = 25° 110 CC 100 SYNC SYNC ...
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LTC3900 pin FuncTions + – (Pin 1, 2): Current Sense Differential Input. + Connect CS through a series resistor to the drain of the external catch MOSFET, Q4. Connect CS The LTC3900 monitors the CS inputs 250ns ...
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Overview In a typical forward converter topology, a power trans- former is used to provide the functions of input/output isolation and voltage step-down to achieve the required low output voltage. Schottky diodes are often used on the secondary-side ...
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LTC3900 applicaTions inForMaTion The timer circuit and current sense comparator in LTC3900 are used to prevent reverse current buildup in the output inductor. Timer Figure 3 shows the LTC3900 timer internal and external circuits. The timer operates by using an ...
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The current sinking capability of the circuit is around 1mA. The timeout function can be disabled by connecting the timer pin to GND. Current Sense The differential input current sense comparator is used for sensing the voltage ...
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LTC3900 applicaTions inForMaTion The value of the resistors CS1 be calculated using the following formulas to meet both the threshold and clamp voltage requirements • I • R –1 RIPPLE DS(ON {200 ...
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An alternative method of generating the SYNC pulse is shown in Figure 8. This circuit produces square SYNC pulses with amplitude dependent on the logic supply voltage. The SYNC pulse width can be adjusted with R1 and C1 ...
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LTC3900 applicaTions inForMaTion the driver dissipation, the total gate charge Q This parameter is found on the MOSFET manufacturers data sheet. The power dissipated in each LTC3900 MOSFET driver is • V • f DRIVER G CC ...
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Typical applicaTions 36V to 72V Input to 12V and 24V (or ± 12V), 2A Output Converter in 1/8th Brick Footprint V IN 36V TO 72V 82k 2.2µ LT1952-1 22k 33k 1 COMP S OUT BC857BF ...
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LTC3900 Typical applicaTions 18V to 40V Input to 14V at 14A Output Converter in 1/4 Brick Footprint V IN 18V TO 40V 6.8µF ×4 LTC4441 1 10 PGND OUT 332k 2 9 220pF BL DRV ...
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Typical applicaTions 36V to 72V Input to 12V, 14A Output Converter in 1/8th Brick Footprint PZTA42 V IN 36V TO 72V 370k LT1952-1 13.3k 7 SD/V OUT SEC 133k OSC 82k 9 BLANK I SENSE 1µF 5 ...
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LTC3900 Typical applicaTions 18V to 72V Input to 12V at 13A Active Reset Converter Fits in 1/8th Brick Size V IN 18V TO 72V 2.2µF × BAS516 LTC4440 220pF V FB ...
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Typical applicaTions PZTA42 V IN 36V TO 72V 82k 2.2µ LT1952-1 22k 33k 1 16 COMP S OUT BC857 1.23V V IN 115k OUT OSC 4 13 SYNC PGND 0.47µF 5 ...
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LTC3900 package DescripTion .050 BSC .245 MIN .030 ±.005 TYP RECOMMENDED SOLDER PAD LAYOUT NOTE: INCHES 1. DIMENSIONS IN (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL ...
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Rev B) REV DATE DESCRIPTION B 5/11 Added H- and MP-grade parts. Reflected throughout the data sheet. Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is ...
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... LTC3726/LTC3725 Synchronous No Opto Forward Converter Controller Chip Set Ideal for Medium Power 24V or 48V Input Isolated Applications LTC3723-1/ Synchronous Push-Pull Controllers LTC3723-2 LTC3721-1/ Nonsynchronous Push-Pull Controllers LTC3721-2 LTC3722/ Synchronous Phase Modulated Full Bridge Controllers LTC3722-2 20 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 ...