LTC1646CGN#TRPBF Linear Technology, LTC1646CGN#TRPBF Datasheet
LTC1646CGN#TRPBF
Specifications of LTC1646CGN#TRPBF
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LTC1646CGN#TRPBF Summary of contents
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... PWRGD, RESETOUT and FAULT Outputs U APPLICATIO S ■ CompactPCI Bus Removable Boards , LTC and LT 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. U TYPICAL APPLICATIO COMPACT PCI COMPACT PCI ...
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LTC1646 ABSOLUTE AXI U RATI GS (Note 1) Supply Voltages ............................................... IN Input Voltages: (Pins 15, 16) ..................... –0.3V to 10V Output Voltages: (Pins .................. –0.3V to 10V Analog Voltages ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Input High Voltage IH V TIMER Threshold Voltage TIMER I OFF/ON Input Current IN RESETIN Input Current 5V Input Current SENSE 3V Input Current SENSE 3V Input Current ...
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LTC1646 W U TYPICAL PERFOR A CE CHARACTERISTICS 5V Undervoltage Lockout IN Voltage vs Temperature 2.60 2.55 LOW-TO-HIGH TRANSITION 2.50 HIGH-TO-LOW TRANSITION 2.45 2.40 –50 – TEMPERATURE (°C) 1646 G04 3V Foldback Current Limit IN Voltage ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Gate I vs Temperature SINK 10 FAULT = –50 – 100 TEMPERATURE (°C) 1646 G13 Power Good Threshold Voltage vs Temperature (5V ) ...
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LTC1646 W U TYPICAL PERFOR A CE CHARACTERISTICS RESETOUT, PWRGD and FAULT Output Low Voltage vs I 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0 (mA) SINK CTIO ...
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CTIO S 3V (Pin 9): 3.3V Current Limit Set. With a sense SENSE resistor placed in the supply path between the GATE pin voltage will be adjusted to maintain SENSE a constant ...
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LTC1646 W TEST DIAGRA DIAGRA Input Mode Window Voltage 3VONLY = ⎟ 5V ⎢ – 3.3V 3.3V 3VONLY IN IN OUT ...
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W BLOCK DIAGRA SENSE OUT +– + 55mV +– – + 150mV +– – 2.5V UVL OFF/ON 15 FAULT 3 Q7 PWRGD 4 Q6 RESETIN 5µA TIMER ...
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LTC1646 U U APPLICATIO S I FOR ATIO 4. Programmable foldback current limit: a programmable analog current limit with a value that depends on the output voltage. If the output is shorted to ground, the current limit drops to keep ...
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U U APPLICATIO S I FOR ATIO GATE 10V/DIV 5V OUT 3V OUT 5V/DIV TIMER 5V/DIV BD_SEL# 5V/DIV HEALTHY# 5V/DIV LCL_PCI_RST# 5V/DIV PRECHARGE 5V/DIV 20ms/DIV Figure 2. Normal Power-Up Sequence Power-Down Sequence When BD_SEL# is pulled high, a power-down sequence ...
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LTC1646 U U APPLICATIO S I FOR ATIO Table TIMER TIMER TIMER TIMER TIMER 0.01µF 2.5ms 0.22µF 0.022µF 5.5ms 0.33µF 0.033µF 8.25ms 0.47µF 0.047µF 11.8ms 0.68µF 0.068µF 17ms 0.82µF 0.082µF 20.5ms 1µF 0.1µF ...
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U U APPLICATIO S I FOR ATIO 5V –5V IN SENSE 100mV/DIV GATE 10V/DIV FAULT 5V/DIV 5µs/DIV Figure 6. Short-Circuit Fault (Pin 12) and 5V (Pin 11) for the 5V supply. For IN SENSE the 3.3V supply, ...
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LTC1646 U U APPLICATIO S I FOR ATIO (RTOL = ±1%, ±2% or ±5%) and standard sense resistor values. Equation 7 can be used to calculate the nominal value from the maximum value found by Equation 6: R SENSE MAX ...
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U U APPLICATIO S I FOR ATIO Table 5. R1 and R2 Resistor Values vs Precharge Voltage PRECHARGE PRECHARGE 1.5V 18Ω 9.09Ω 0.9V 1.4V 18Ω 7.15Ω 0.8V 1.3V 18Ω 5.36Ω 0.7V 1.2V 18Ω 3.65Ω 0.6V 1.1V ...
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LTC1646 U U APPLICATIO S I FOR ATIO COMPACT PCI BACKPLANE CONNECTOR (MALE) 5V LONG 5V GND Z1: BZX84C6V2 If no 3.3V supply is present, Figure 11 illustrates how the LTC1646 should be configured. First, 3V connected to 3V (Pin ...
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U U APPLICATIO S I FOR ATIO Since there is no bulk capacitance to damp the parasitic trace inductance, supply voltage transients excite para- sitic resonant circuits formed by the power MOSFET capacitance and the combined parasitic inductance from the ...
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LTC1646 U U APPLICATIO S I FOR ATIO PCB Layout Considerations For proper operation of the LTC1646’s circuit breaker function, a 4-wire Kelvin connection to the sense resistors is highly recommended. A recommended PCB layout for the sense resistor, the ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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. ...
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... Supplies for PCI Bus 3.3V, 5V, ±12V Local Reset Logic and Precharge Operates from 1.2V to 12V, Power Sequencing Dual ON Pins for Supplies from 3V to 15V Single Supply, 2.5V to 16.5V, MSOP LT 1205 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2000 1646fa ...