LTC4242IUHF#PBF Linear Technology, LTC4242IUHF#PBF Datasheet
LTC4242IUHF#PBF
Specifications of LTC4242IUHF#PBF
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LTC4242IUHF#PBF Summary of contents
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... PGOOD and AUXPGOOD outputs indicate proper main and auxiliary supply outputs. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...
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LTC4242 ABSOLUTE AXI U RATI GS Supply Voltages V ........................................................... –0. 12V .................................................... –0.3V to 20V INn 3V ...................................................... –0.3V to 10V INn AUXINn .................................................. –0.3V to 10V Input Voltages ONn, AUXONn, FONn ............................... ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T (Note 2) SYMBOL PARAMETER Supplies V Operating Voltage IN I Input Supply Current 12V INn 3V INn V Supply Undervoltage Lockout UVL ΔV Supply Undervoltage Lockout Hysteresis ...
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LTC4242 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T (Note 2) SYMBOL PARAMETER V ONn, AUXONn Pin Threshold Voltage ON(TH) ΔV ONn, AUXONn Pin Hysteresis ON(TH) V ONn, AUXONn Pin Reset Threshold Voltage ON(RTH) I ONn, AUXONn Pin ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS T = 25° 3.3V AUXINn 3VINn 3.0 2.5 1.0 1.5 1 (V) CC 4242 ...
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LTC4242 W U TYPICAL PERFOR A CE CHARACTERISTICS T = 25° 3.3V AUXINn 3VINn FONn Low-to-High Threshold ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS T = 25° 3.3V AUXINn 3VINn Gate Drive vs Temperature 6.0 5.8 5.6 5.4 5.2 5.0 – –25 TEMPERATURE (°C) I Off ...
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LTC4242 CTIO S 12V /12V : Gate Drive for 12V Supply External GATE1 GATE2 N-Channel MOSFET. An internal charge pump provides a 9µA pull-up current to ramp up 12V off, a 1mA pull-down current source ...
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CTIO S AUXPGOOD1/AUXPGOOD2 (QFN): AUX Supply Power Status Output. This open-drain pin is pulled high by an internal 9µA pull-up when AUXOUTn is below power good threshold, when ENn is high, during thermal shutdown, AUXONn ...
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LTC4242 CTIO AL DIAGRA OSCILLATOR ENn ONn FONn AUXONn 12V INn 12V SENSEn 12V OUTn 7. INn 3V SENSEn 3V OUTn 1.31R R AUXINn 10 W CP12V CHARGE V CC CP3V PUMP CPAUX 12V IN ...
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U OPERATIO The Functional Diagram displays the main functional ele- ments of this device. The LTC4242 is designed to control the power for two independent slots on a PCI Express backplane, allowing two boards to be safely inserted and removed. ...
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LTC4242 U U APPLICATIO S I FOR ATIO R1 8mΩ 12V 3. 47Ω 15nF 12V 12V IN1 33Ω 1µF 9 AUXIN1 4 MRL1 AUXON1 3 ON1 PWREN1 BD_PRST1 ...
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U U APPLICATIO S I FOR ATIO SYSTEM BOARD CONNECTOR OUT LTC4242 Figure 3. RC Network to Generate Delay During Card Plug-In When PRSNT2 pulls low after insertion of a board, the ENn pin goes low after a delay as ...
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LTC4242 U U APPLICATIO S I FOR ATIO for the 3.3V auxiliary power paths. Sense resistors provide input for current fault detection. Resistors and capacitors compensate the current ...
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U U APPLICATIO S I FOR ATIO ENn 5V/DIV AUXOUTn 5V/DIV 12V OUTn 5V/DIV 3V OUTn 5V/DIV PGOODn 5V/DIV 100ms/DIV Figure 5. Normal Power-Down Sequence Thermal Shutdown Each of the two internal switches for the 3.3V auxiliary supplies is protected ...
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LTC4242 U U APPLICATIO S I FOR ATIO AUXFAULTn 5V/DIV AUXOUTn 5V/DIV AUXINn 5V/DIV I LOAD 5A/DIV 5µs/DIV Figure 8. Short-Circuit Fault on 3.3V MOSFET shuts off (see Supply Transients). The compen- sation network R /C assists the gate voltage ...
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U U APPLICATIO S I FOR ATIO R2 Q2 13mΩ Si7336ADP 3.3V 3V GATE 3V 3V SENSE OUT AUTO LTC4242* 200k BD_PRST FAULT AUTO GND 0.1µF *ADDITIONAL DETAILS OMITTED FOR CLARITY Figure 9. Auto-Retry ...
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LTC4242 U U APPLICATIO S I FOR ATIO Yet another mode of operation is the Force ON with cur- rent limit mode. To enter this mode, pull both FON and EN high. In this mode of operation, the ACLs are ...
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U U APPLICATIO S I FOR ATIO In system board applications, large bypass capacitors (≥10µF) are recommended at each of the system input supplies to minimize supply glitches as a result of large inrush or fault currents important ...
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LTC4242 U U APPLICATIO S I FOR ATIO Using P and t to look up the MOSFETs’ single pulse ON 1 θ from the manufacturer’s Transient Thermal JA(MAX) Impedance Graph, the worst-case junction-to-ambient temperature rise occurs for the 12V MOSFET. ...
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U TYPICAL APPLICATIO LTC4242 4242f 21 ...
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LTC4242 PACKAGE DESCRIPTIO 7.8 – 8.2 0.42 ±0.03 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 0.09 – 0.25 0.55 – 0.95 (.022 – .037) (.0035 – .010) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN ...
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... DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 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. U UHF Package 38-Lead Plastic QFN (5mm × ...
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... Ultralow Voltage Hot Swap Controller ® LT 4220 Dual Supply Hot Swap Controller LTC4221 Dual Hot Swap Controller LTC4241 PCI-Bus Hot Swap Controller trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 ● (408) 432-1900 FAX: (408) 434-0507 Si7336ADP 0.4Ω ...