LTC4240CGN#TR Linear Technology, LTC4240CGN#TR Datasheet
LTC4240CGN#TR
Specifications of LTC4240CGN#TR
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LTC4240CGN#TR Summary of contents
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... APPLICATIO S Hot Board Insertion into CompactPCI Bus Electronic Circuit Breaker , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. QuickSwitch is a registered trademark of Quality Semiconductor Corp. CompactPCI is a trademark of the PCI Industrial Computer Manufacturers Group. ...
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LTC4240 ABSOLUTE AXI U RATI GS (Notes 1, 2) Supply Voltages 5V IN .................................................................... 12V IN ................................................................. V EEIN ................................................................... Input Voltages PRSNT1#, PRSNT2#, SCL, RESETIN, OFF/ON .................................................. –0.3V to 12V ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V 12V Switch Voltage Drop 12V V V Switch Voltage Drop VEE EE I Current Foldback CL I Current Fault Threshold TH T Thermal Shutdown Temperature TS V Power ...
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LTC4240 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER t Stop Condition Setup Time SUSTP t Data Hold Time HDDAT t Data Setup Time SUDAT t Clock Low Period LOW t Clock High Period HIGH t Clock/Data ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS V Supply Current EEIN vs Temperature –0.8 OFF/ –0.9 –1.0 –1.1 –1.2 –50 – 100 TEMPERATURE ( C) 4240 G07 12V Output Current 1.6 12V = 12V ...
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LTC4240 W U TYPICAL PERFOR A CE CHARACTERISTICS 3V Input Current SENSE vs Temperature 3.3V SENSE –50 – 100 TEMPERATURE ( C) 4240 G16 Timer Pin Turn-On Current vs ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS V UVLO Threshold Voltage EEIN vs Temperature –7.6 –8.0 –8.4 –8.8 –9.2 –9.6 –10.0 – 100 –25 TEMPERATURE ( C) 4240 G25 3V Foldback Current Limit Voltage vs Temperature ...
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LTC4240 CTIO S PRSNT1# (Pin 1): PCI Present Detect Input 1. PRSNT1# and PRSNT2# are readable over the I and PRSNT2# indicate the maximum power used by the card. Do not float. PRSNT2# (Pin 2): ...
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CTIO S node. An external 1k resistor between the transistor’s base and 3V is needed. IN PRECHARGE (Pin 18): Precharge Monitor Input. An inter- nal error amplifier servos the DRIVE pin voltage to keep the ...
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LTC4240 W BLOCK DIAGRA SENSE OUT 70mV, +– + TIMER LO 165mV, A1 TIMER HI +– – + CP1 55mV +– – 4.3V UVL OFF/ON 28 FAULT 7 Q13 PWRGD 8 Q12 ...
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U U APPLICATIO S I FOR ATIO The LTC4240 is a Hot Swap controller that allows a board to be safely inserted and removed from a CompactPCI bus slot. The LTC4240 has built-in 2-wire I interface hardware to allow software ...
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LTC4240 U U APPLICATIO S I FOR ATIO used to turn off/on the power switches, turn on the status LED (alerting the user that its safe to remove the plug-in board), and assert the LOCAL_PCI_RST# signal. The I bus is ...
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U U APPLICATIO S I FOR ATIO START and STOP Commands The START command is defined as a high to low transition of the SDA line while the SCL line is high asynchro- nous event issued by ...
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LTC4240 U U APPLICATIO S I FOR ATIO ADDRESS BYTE SCL START SDA 0 1 ADDR 4 ADDR 3 ADDR 2 Table 2. Command Byte Definitions HIGH C7 Don’t care C6 Don’t care C5 Ignore V ...
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U U APPLICATIO S I FOR ATIO Table 3 shows the definition for each data bit. PWRGD, FAULT, RESETIN, and RESETOUT external pins can be monitored. PRSNT1# and PRSNT2# are PCI signals that provide information on the power requirements of ...
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LTC4240 U U APPLICATIO S I FOR ATIO stage in the hot plug sequence, indicating that the LTC4240 is in reset mode with all power switches off (BD_SEL# is still pulled high to long 5V). The 12V and –12V supplies ...
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U U APPLICATIO S I FOR ATIO Note that capacitor C1 performs dual functions. In addi- tion to controlling the ramp up rates of the 5V and 3.3V outputs, it also compensates the current limit loop. Current limit faults are ...
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LTC4240 U U APPLICATIO S I FOR ATIO Timer During a power-up sequence, an 11.5 A current source is connected to the TIMER pin (Pin 5) and charges up the external TIMER pin capacitor. Current limit faults are ignored until ...
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U U APPLICATIO S I FOR ATIO Once the TIMER voltage has reached 5.5V, all of the supplies will be latched off if any supply enters current limit for at least 35 s. The 35 s delay prevents quick current ...
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LTC4240 U U APPLICATIO S I FOR ATIO sense resistor drops to 0.0049 and the largest value of threshold voltage increases to 60mV. This results in a trip current of 12.2A LOAD(MAX) SENSE ...
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APPLICATIO S I FOR ATIO Transient Power Dissipation There are certain transient events that can significantly increase the power dissipated by the external FET. If the LTC4240 5V supply ( 10%) powers up into a ...
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LTC4240 U U APPLICATIO S I FOR ATIO Table 6. R1 and R2 Resistor Values vs Precharge Voltages V R11A R11B V PRECHARGE PRECHARGE 1.5V 18 9.09 0.9V 1.4V 18 7.15 0.8V 1.3V 18 5.36 0.7V 1.2V 18 3.65 0.6V ...
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U U APPLICATIO S I FOR ATIO than 2 A, then a 50K resistor can be connected directly from the 1V bias voltage to the I/O line. However, many ICs connected to the I/O lines can have leakage currents up ...
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LTC4240 U U APPLICATIO S I FOR ATIO The assumption by the CompactPCI specification is that there is a diode to 3.3V on the circuit that is driving the BD_SEL# pin. The 1.2k resistor pull card ...
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U U APPLICATIO S I FOR ATIO Disallowing bulk capacitors on the input power pins mitigates the inrush current during hot plug. However, it also tends to create a resonant circuit formed by the inductance of the backplane power supply ...
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LTC4240 U U APPLICATIO S I FOR ATIO Note (see front page schematic) that the 12V and –12V show 0.01 F snubber capacitors. This is consistent with the CPCI specification since we also recommend a 10 snubber resistor. The 12V ...
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... Vishay-Dale Vishay-Siliconix Diodes, Inc. 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 PART NUMBER ...
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... Eliminates ORing Diodes, Identifies and Localizes Faults www.linear.com .386 – .393* .033 (9.804 – 9.982) (0.838 1615 REF .150 – .157** (3.810 – 3.988 .004 – .009 (0.102 – 0.249) .0250 (0.635) BSC GN28 (SSOP) 0502 LT/TP 0403 2K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2003 4240f ...