LT1619 Linear Technology, LT1619 Datasheet
LT1619
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LT1619 Summary of contents
Page 1
... The oscillator can also be synchronized exter- nally up to 500kHz. No load quiescent current is 140 A and shutdown current The LT1619 is available in 8-lead MSOP and SO packages. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. ...
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... Measured at the FB Pin 1.9V V 18V REF COMP V = 1.5V COMP 1.9V V 18V IN ORDER PART NUMBER TOP VIEW LT1619ES8 7 DRV 6 GATE SENSE 5 S8 PART MARKING S8 PACKAGE 1619 = 125 C, = 120 MIN TYP MAX 1.22 1.24 1.26 0.004 0. 170 260 4 8.7 ...
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... Shutdown Delay Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: The LT1619E is guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LT1619 W U TYPICAL PERFOR A CE CHARACTERISTICS Shutdown Supply Current vs Input Voltage – INPUT VOLTAGE (V) 1619 G04 Maximum Duty Ratio vs Temperature 2. –40 –20 ...
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... V (Pin 8): Supply or Battery Input. Must be closely IN bypassed to the ground plane. UVLO A2 IDLE – I CURRENT LIM LIMIT COMPARATOR Figure 2. LT1619 Block Diagram . SENSE (Pin 8) for nonbootstrapped operation DRV 7 GATE DRIVER 6 SENSE 5 GND – 4 CURRENT ...
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... IC supply current therefore be- comes a small fraction of the total input current. Setting Output Voltage The output voltage of the LT1619 is set with resistive divider R1 and R2 connected from the output to ground as detailed in Figure 3. The divider tap is tied to the device FB pin. Current through R2 should be significantly higher than the FB pin bias current of 25nA ...
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... S/S pin voltage rises above the shutdown threshold. Applying a logic low signal at the S/S pin causes the gate drive output to go low. Although all circuits in the LT1619 are disabled, the pull-down circuit in the MOSFET buffer is still biased on capable of shunting any leakage or transient current at the GATE pin to ground, eliminating the need for an external bleed resistor ...
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... S Current Sensing Resistor R ) The LT1619 drives a low side N-channel MOSFET switch. The switch current is sensed with an external resistor R connected between the source of the MOSFET and SENSE ground. The internal blanking circuit blocks the voltage spike developed across R on ...
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... For the boost converter in Figure 1, the peak inductor current is approximately 5A. A Motorola MBRD835 is used due to its low forward voltage. Lowering Burst Mode Operation Current Limit The LT1619 automatically enters Burst Mode operation as V voltage falls below V . The corresponding switch ...
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... Consider the 12V to – 65V isolated flyback converter (see Typical Applications). The converter draws 3A at low line while delivering 0.4A to the output. If the S/S pin is tied to the input, then the LT1619 will start switching as soon as V exceeds the internal UVLO threshold. With full load, ...
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... Trip Points of 10V and 8.4V. In UVLO, the Gate Drive IN is Disabled by Pulling the V Pin Low. Disabling the Clock Shuts C Down the LT1619. If Not Synchronized, the Collector of Q2 Can Be Tied to the S/S Pin and the Diode D1 Can Be Eliminated W U The collector votage made about 1.4V at the V lower trip voltage ...
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... U U APPLICATIO S I FOR ATIO Increasing Ramp Compensation While Synchronizing The LT1619 is synchronized by forced discharge of the internal timing ramp. The timing ramp amplitude de- creases as the synchronization frequency increases. Since the internal compensation ramp is derived from the timing ramp, reduced timing ramp results in diminished com- pensating ramp ...
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... APPLICATIO S I FOR ATIO C Z Figure 14. Recommended Component Placement for the Boost Converters in Figures 15a and 16a IN2 LT1619 SENSE GND C C IN1 OUT1 OUT LT1619 C DRV 1619 F14 1619fa 13 ...
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... LT1619 U U APPLICATIO S I FOR ATIO 1 S LT1619 75k P GND 150pF C Z 15nF C : SANYO POSCAP 6TPB150M 2 IN1 C : SANYO POSCAP 10TPB220M 4 OUT1 D1: MOTOROLA MBRB1545CT L1: SUMIDA CEPH149-1R0 R : PANASONIC 0.002 1W SENSE IN2 CERAMIC 7 DRV + C DRV C IN1 0 300 F ...
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... GATE 5 SENSE Figure 16a 12V/5A Boost Converter 0.01 0.1 1 LOAD CURRENT (A) 1619 F16b Figure 16b. Efficiency of the 12V/5A Boost Converter LT1619 1.8 H 12V FDS6690A C OUT2 107k CERAMIC OUT1 R 600 F R2 ...
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... T1: COILTRONICS CTX02-14261, EFD20-3F3, 6 WINDINGS EACH • • • • • 15 • 8 S FILM 7 FB DRV LT1619 10 F SUD45N05-20L 6 V GATE 50V, 0.018 C 43nC 5 GND SENSE 0.007 Figure 17a – 48V Cuk Converter 5.25V ...
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... TRIFILAR 28AWG 0.008 W1 6T TRIFILAR 28AWG 13. 12V 10. 100 1000 LOAD CURRENT (mA) 1619 F18b LT1619 10k CNY17-3 6.2V 220pF 470 100 62k 470pF 121 LT1431 1 8 COLL REF 2 7 –32. FGND SGND 2.49k – ...
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... LT1619 PACKAGE DESCRIPTION 5.23 (.206) MIN 0.42 0.04 (.0165 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) GAUGE PLANE 0.18 (.077) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006" ...
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... TYP INCHES (MILLIMETERS) .189 – .197 (4.801 – 5.004) NOTE .150 – .157 (3.810 – 3.988) NOTE 3 N .004 – .010 (0.101 – 0.254) .050 (1.270) BSC SO8 0502 LT1619 1619fa 19 ...
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... Power Supply Solution with Multiple Outputs Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 FMMT3904 MBRS0530T1 Q3 MMFT3055VL DRV GATE SENSE LT1619 2 FB S/S GND 220pF 0.015 C8 2. 16V 2.2nF -28V to 5V/0.5A Nonisolated Supply IN ...