LTC1159 Linear Technology, LTC1159 Datasheet
LTC1159
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LTC1159 Summary of contents
Page 1
... The output current level is user pro- grammable via an external current sense resistor. The LTC1159 automatically switches to power saving Burst Mode operation when load current drops below approximately 15% of maximum current. Standby current is only 300 A while still regulating the output and shut- down current is a low 20 A ...
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... PLASTIC SSOP T = 125 C, = 135 C/ W JMAX JA Consult factory for Industrial and Military grade parts. ELECTRICAL C HARA TERISTICS C SYMBOL PARAMETER V Feedback Voltage (LTC1159 Only Feedback Current (LTC1159 Only Regulated Output Voltage OUT LTC1159-3.3 LTC1159-5 V Output Voltage Line Regulation OUT Output Voltage Load Regulation LTC1159-3 ...
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... J dissipation P according to the following formulas: D LTC1159CG, LTC1159CG-3.3, LTC1159CG-5: T LTC1159CN, LTC1159CN-3.3, LTC1159CN-5: T LTC1159CS, LTC1159CS-3.3, LTC1159CS-5: T Note 2: On LTC1159 versions which have a SHDN1 pin, it must be at ground potential for testing. Note 3: The LTC1159 V and EXTV current measurements exclude IN CC MOSFET driver currents. When V ...
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... T = 70°C 1.0 0 – VOLTAGE (V) IN OUT Current Sense Threshold Voltage 160 140 MAXIMUM THRESHOLD 120 100 MINIMUM THRESHOLD TEMPERATURE (°C) = 24V 2.0 2.5 LTC1159 • TPC03 T = 25° LTC1159 • TPC06 80 100 LTC1159 • TPC09 ...
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... Sense pin (LTC1159-3.3 and LTC1159- external divider returned to the V (LTC1159). A voltage comparator V, and a gain block G, compare the divided output voltage with a reference voltage of 1.25V. To optimize efficiency, the LTC1159 automatically switches between two modes of operation, burst and continuous. ...
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... W Internal divider broken at V for adjustable versions. FB 550k – – V TH1 T + OFF-TIME – SENSE CONTROL P-GATE CC 550k P-DRIVE N-GATE + SENSE SENSE P-GND – 25mV TO 150mV V OS – 13k 1.25V FB REFERENCE SHDN1 S-GND – 100k LTC1159 • FD ...
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... SENSE I MAX A graph for selecting R versus maximum output SENSE current is given in Figure 2. The LTC1159 series works well with values of R from 0.02 to 0.2 . SENSE The load current below which Burst Mode operation com- mences and the peak short-circuit current, I BURST LTC1159/LTC1159-3.3/LTC1159-5 ...
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... Burst Mode operation to be falsely triggered in the LTC1159. Do not allow the core to saturate! Molypermalloy (from Magnetics, Inc low loss core material for toroids, but it is more expensive than ferrite. ...
Page 9
... MOSFET RSS electrical characteristics. The constant can be used for the LTC1159 to estimate the relative contributions of the two terms in the P-channel dissipation equation. The Schottky diode D1 shown in Figure 1 only conducts during the dead time between the conduction of the two power MOSFETs ...
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... The solution is to add a diode between the cap and V LTC1159 • TPC04 pins of the LTC1159 as shown in several of the typical OUT application circuits. If you think your system could have this problem, add the diode. Note that in surface mount and can be ...
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... SHDN1 pin, ensuring complete shutdown SENSE V OUT Note: For versions in which both the SHDN1 and SHDN2 pins are available (LTC1159G and all fixed output ver- + BAT85 VN2222LL sions), the two pins are simply connected to each other and C OUT driven together to guarantee complete shutdown ...
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... Inverting Regular Applications The LTC1159 can also be used to obtain negative output voltages from positive inputs. In these inverting applica- tions, the current sense resistor connects to ground while the LTC1159 and N-channel MOSFET connections, which would normally go to ground, instead ride on the negative output ...
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... Auxiliary Windings – Suppressing Burst Mode Operation The LTC1159 synchronous switch removes the normal limitation that power must be drawn from the inductor primary winding in order to extract power from auxiliary LTC1159/LTC1159-3.3/LTC1159-5 ...
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... close as possible to the LTC1159 100 may be placed in series with each sense lead to help decouple the Sense pins. However, when these resistors are used, the capacitor should be no larger than 1000pF. 4) Does the (+) plate of C P-channel MOSFET as closely as possible? An addi- tional 0 ...
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... U U APPLICATIONS INFORMATION Troubleshooting Hints Since efficiency is critical to LTC1159 applications it is very important to verify that the circuit is functioning correctly in both continuous and Burst Mode operation. The wave- form to monitor is the voltage on the C In continuous mode (I > I LOAD BURST a sawtooth with a 0.9V swing. This voltage should never P-P dip below 2V as shown in Figure 9a ...
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... SENSE 20 H 0.04 VN2222LL BAT85 BAT85 + 0.22 F BAT85 + 1 F LTC1159 • F11 V IN 15V TO 40V + 1200 F 50V 2 LXF SMP40P06 HEAT SINK SENSE 22 H 0.01 MTP75N05HD MBR350 100 100 LTC1159 • F12 V OUT 3.3V/2.5A 330 F 6.3V 2 AVX 1 F WIMA V OUT 5V/10A + 220 F 10V 3 OS-CON ...
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... WIMA IRF9Z34 SXC HEAT SINK SENSE 50 H 0.02 + IRFZ44 MBR350 150 F 16V OS-CON 90.9k 1% LTC1159 • F13 *COILTRONICS CTX50-5-KM **IRC LO-3-0. WIMA • Si9410DY 100k BAS16 0. 220 F 10V 4 + AVX BAS16 ** LTC1159 • F14 V OUT 12V/ OUTPUT + 220 F 10V 2 AVX 3.3V OUTPUT 17 ...
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... Q3 SHUTDOWN TP0610L 20k 5.1V 510k 1N5993 * DALE TJ4-100-1 ** IRC LR2512-01-R050 1N4148 0. P-GATE CAP SHDN2 EXTV 0 LTC1159 4 13 P-DRIVE N-GATE 1N5818 3 P-GND + S-GND (SHDN1) 6800pF 8 9 – + SENSE SENSE ...
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... 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC1159/LTC1159-3.3/LTC1159-5 U Dimensions in inches (millimeters) unless otherwise noted. ...
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... DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm). COMMENTS Dual Version of LTC1148 Dual Version of LTC1147 Nonsynchronous, 8-Lead, V Synchronous, V Synchronous, V 0.5A Switch, V 1.2A Switch, V Dual Version of LTC1159 : 499-3977 0.386 – 0.394* (9.804 – 10.008 0.150 – 0.157* (3.810 – ...