LTC4224-2 Linear Technology, LTC4224-2 Datasheet
LTC4224-2
Related parts for LTC4224-2
LTC4224-2 Summary of contents
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... A FAULT pin signals overcurrent faults. The LTC4224-1 remains off after a fault, while the LTC4224-2 automatically tries to apply power again after a four second cool-down period. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation ...
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... LTC4224-1/LTC4224-2 www.DataSheet4U.com ABSOLUTE MAXIMUM RATINGS Supply Voltage (V ) .................................. –0. CCn Input Voltages SENSEn, ONn ........................................... –0. Output Voltages GATEn – V (Note 4) .............................. –0. FAULT ....................................................... –0. PIN CONFIGURATION TOP VIEW SENSE1 CC1 3 11 GATE1 FAULT 4 ON1 5 DDB PACKAGE 10-LEAD (3mm × 2mm) PLASTIC DFN = 125° ...
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... FAULT ΔV – SENSEn) High to = 200mV, C CCn SENSE V Out Note 3 Note 3: LTC4224-2 only. Note 4: The greater internal clamp limits the GATE pin to a minimum 5V above V this pin beyond the clamp may damage the device. LTC4224-1/LTC4224-2 MIN TYP ...
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... LTC4224-1/LTC4224-2 www.DataSheet4U.com TYPICAL PERFORMANCE CHARACTERISTICS Specifi cations are T = 25° 5V CC1 1.5 1.4 1.3 1.2 1.1 1.0 2.5 3 3 (V) CC Gate Drive vs I GATE –2 –4 –6 –8 –10 I (μA) GATE Gate Fast Pull-Down Current vs Gate Voltage ...
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... V UV CC1 + LOGIC CONTROL – CC2 ECB2 + – CHARGE PUMP 10μA ACL2 + V CC – SENSE2 GND LTC4224-1/LTC4224 exter- CC1 CC2 by a 10μA current source. 5. GATE1 V CC GATE PULLDOWN 10μA ON1 + ON1 – 0.8V FAULT V CC 10μA ...
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... FAULT is latched low to indicate an overcurrent fault. The LTC4224-1 remains latched off until reset by either turning off and then on the affected supply or its ON pin. The LTC4224-2 automatically restarts after four seconds to allow time for the MOSFET to cool down. The basic LTC4224 application circuit is shown in Figure 1. ...
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... GATE2 5V/DIV 5ms/DIV Figure 2. Normal Power-Up Sequence LTC4224-1/LTC4224-2 10μA charge pump generated current source. When the GATE voltage reaches the MOSFET threshold voltage, the inrush current can build up quickly as the GATE continues to rise. The ACL amplifi er actively controls the gate volt- age to maintain 25mV across the sense resistor ...
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... LTC4224-1/LTC4224-2 www.DataSheet4U.com APPLICATIONS INFORMATION If the voltage across the sense resistor R1 becomes too high, the inrush current is limited by the internal current limit circuitry. Turn-Off Sequence The MOSFETs can be turned off by the conditions sum- marized in Table 1. Table 1. Turn-Off Conditions RESULT CONDITION CHANNEL 1 ...
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... MOSFET latches off. Figure 7 shows how the output latches off following an overcurrent fault. During a severe short-circuit (see Figure 8), the output load current can briefl y surge to tens of amperes. The LTC4224 rapidly brings the current under control by discharging LTC4224-1/LTC4224-2 GATE1 5V/DIV V OUT1 ...
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... UV turn-on delay. When both supplies are above 2.5V, either supply going low only resets its own fault. For the auto-retry version (LTC4224-2), if the fault is not cleared within four seconds, the latched fault will be cleared automatically. FAULT will go high and the turn-on sequence will begin ...
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... Table 2. Sense Resistor Values SUPPLY VOLTAGE 3.3V TOP SIDE For proper operation, I 422412 F12 mum load current with margin SENSE2 supplies respectively. LTC4224-1/LTC4224-2 = 3.3V 1A, I CC2 LOAD1(MAX) LOAD2(MAX 150μF (see Figure 1). LOAD2 . R (1%) ...
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... If both supplies are short-circuited, the junction temperature will increase by 50°C in the worst-case. During auto-retry (LTC4224-2), in the event of persistent faults at both supplies, the ample four second cooling delay limits the increase in junction temperature to 50° ...
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... SENSE1 GATE1 CC1 10k FAULT BACKPLANE ON1 CONNECTOR1 LTC4224 ON2 GND BACKPLANE V SENSE2 GATE2 CONNECTOR2 CC2 PRSNT2 R2 Q2 0.004Ω Si7336ADP LTC4224-1/LTC4224-2 Q1 Si7336ADP Si7336ADP 3.3V 5A SENSE2 GATE1 GATE2 422412 TA02 5V 5A CARD CONNECTOR1 CARD CONNECTOR2 5V 5A 422412 TA03 422412fa ...
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... LTC4224-1/LTC4224-2 www.DataSheet4U.com PACKAGE DESCRIPTION 0.64 ±0.05 (2 SIDES) 2.55 ±0.05 1.15 ±0.05 0.25 ± 0.05 0.50 BSC 2.39 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING CONFORMS TO VERSION (WECD-1) IN JEDEC PACKAGE OUTLINE M0-229 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH ...
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... TYP 0.53 ± 0.152 (.021 ± .006) DETAIL “A” SEATING PLANE 0.17 – 0.27 (.007 – .011) TYP LTC4224-1/LTC4224-2 0.497 ± 0.076 (.0196 ± .003 REF 3.00 ± 0.102 (.118 ± .004) (NOTE ...
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... LTC4224-1/LTC4224-2 www.DataSheet4U.com TYPICAL APPLICATION APS BULK SUPPLY BYPASS CAPACITOR 3.3V BULK SUPPLY BYPASS CAPACITOR APS 1.8V RELATED PARTS PART NUMBER DESCRIPTION LTC1421 Two Channel Hot Swap Controller LTC1645 Dual Channel Hot Swap Controller LTC1647 Dual Channel Hot Swap Controller LTC4210 Single Channel Hot Swap Controller ...