LTC1643LCGN Linear Technology, LTC1643LCGN Datasheet
LTC1643LCGN
Specifications of LTC1643LCGN
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LTC1643LCGN Summary of contents
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... On-Chip Switches I Fault and Power-Good Outputs I APPLICATIO S U PCI-Based Servers I CompactPCI Compliant Boards I , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. CompactPCI is a trademark of PCI Industrial Computer Manufacturing Group. TYPICAL APPLICATION U SYSTEM POWER SUPPLY 8 ...
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... V = – 12V EEIN EEOUT 12VOUT LTC1643H/LTC1643L Only – EEOUT LTC1643H/LTC1643L Only – INFORMATION ORDER PART NUMBER TOP VIEW 16 12V OUT LTC1643HCGN 15 V EEOUT LTC1643LCGN 14 5V OUT LTC1643L-1CGN LTC1643HIGN 12 5V SENSE LTC1643LIGN 11 GATE 10 3V SENSE GN PART MARKING 1643H GN PACKAGE 1643L 1643L1 ...
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DC ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 12V – 12V 3.3V, V 12VIN EE 3VIN SYMBOL PARAMETER V Power-Good ...
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LTC1643L/LTC1643L-1/LTC1643H W U TYPICAL PERFORMANCE CHARACTERISTICS Timer Current vs Temperature 23.5 23.0 22.5 22.0 21.5 21.0 20.5 20.0 19.5 –50 – 100 TEMPERATURE ( C) 1643 G04 Power Good Threshold Voltage vs Temperature (12V ) OUT ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Circuit Breaker Trip Filter Time vs Temperature 15.50 15.25 15.00 14.75 14.50 14.25 14.00 –50 – 100 125 TEMPERATURE ( C) 1643 G13 V Supply Current EEIN vs Temperature 0.90 0.89 ...
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LTC1643L/LTC1643L-1/LTC1643H W U TYPICAL PERFORMANCE CHARACTERISTICS 3V Undervoltage Lockout IN vs Temperature 2.454 2.452 2.450 2.448 2.446 2.444 2.442 –50 – 100 125 TEMPERATURE ( C) 1643 G21 V Current Foldback EE vs Temperature 600 500 ...
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PIN FUNCTIONS the ON pin pulled low, the GATE pin is pulled high current source and the internal 12V and – 12V switches are turned on. When the ON pin is pulled low ...
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LTC1643L/LTC1643L-1/LTC1643H PIN FUNCTIONS V (Pin 15): –12V Supply Output. A 1.2 switch is EEOUT connected between V and V EEIN exceed –10.8V before the PWRGD signal can go high on the LTC1643H and LTC1643L. W BLOCK DIAGRAM ...
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U U APPLICATIONS INFORMATION LTC1643 FEATURE SUMMARY 1. Allows safe board insertion and removal from either a motherboard (LTC1643H) or CompactPCI board (LTC1643L/LTC1643L-1). 2. Controls all four PCI supplies: –12V, 12V, 3.3V and 5V. 3. Programmable foldback current limit: a ...
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LTC1643L/LTC1643L-1/LTC1643H U U APPLICATIONS INFORMATION SYSTEM POWER SUPPLY 10k PCI 6 POWER SYSTEM R4 CONTROLLER 10k 7 RESET ON 10V/DIV TIMER 10V/DIV GATE 10V/DIV 12V OUT 5V/DIV 5V OUT 5V/DIV 3V OUT 5V/DIV V EEOUT ...
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U U APPLICATIONS INFORMATION Timer During a power-up sequence current source is connected to the TIMER pin (Pin 4) and current limit faults are ignored until the voltage ramps to within 0.9V of 12V (Pin 1). This ...
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LTC1643L/LTC1643L-1/LTC1643H U U APPLICATIONS INFORMATION ON 10V/DIV TIMER 10V/DIV GATE 10V/DIV 12V OUT 5V/DIV 3V OUT 5V/DIV 5V OUT 5V/DIV V EEOUT 5V/DIV FAULT 10V/DIV PWRGD 10V/DIV 20ms/DIV Figure 4. Power-Up into a Short on 3.3V Output 5V 3.3V 3 ...
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U U APPLICATIONS INFORMATION MED 5V MED 3.3V R11 † 1 V(I/ 12V 1.2k 0 12V R12 3 5% –12V BD_SEL# V(I/O) V(I/O) R13 D2* 2k R10 2k 5% 12V 5% ...
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LTC1643L/LTC1643L-1/LTC1643H U U APPLICATIONS INFORMATION For the 12V supply, P-channel transistor Q4 is placed in parallel with the internal switch. When the LTC1643H is turned off, the GATE pin is held low and transistor Q3 is turned on which pulls ...
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... CONTROLLER R4 10k 7 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. LTC1643L/LTC1643L-1/LTC1643H U GN Package 16-Lead Plastic SSOP (Narrow .150 Inch) (Reference LTC DWG # 05-08-1641) 0.229 – ...
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... Operation, Multifunction Current Control – 20V to 80V Supplies, Active Current Limiting –15V Minimum Floating Supply, Active Current Limiting Floating Supply, Power Good, Active Current Limiting 1643fa LT/TP 0801 1.5K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 LONG 3.3V IN ...