LTC1643AL-1IGN Linear Technology, LTC1643AL-1IGN Datasheet
LTC1643AL-1IGN
Specifications of LTC1643AL-1IGN
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LTC1643AL-1IGN Summary of contents
Page 1
... FAULT output indicates an overcurrent condition. The ON(LTC1643AH)/ON (LTC1643AL/ LTC1643AL-1) pin is used to cycle the board power or reset the circuit breaker. The LTC1643AL-1 has the ±12V power good comparators disabled. The LTC1643A is available in a 16-pin narrow SSOP package. ...
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... U W INFORMATION ORDER PART NUMBER LTC1643AHCGN TOP VIEW LTC1643ALCGN 16 12V OUT LTC1643AL-1CGN 15 V EEOUT LTC1643AHIGN 14 5V OUT 13 5V LTC1643ALIGN LTC1643AL-1IGN SENSE 11 GATE GN PART MARKING 10 3V SENSE 1643AH 1643AL GN PACKAGE 643AL1 643AHI 643ALI = 135° 43AL1I http://www.linear.com/leadfree/ = 3.3V (Note 2) 3VIN 5VIN ...
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... Note 2: All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to ground unless otherwise specified. 12V Current Foldback Profile 1.0 0 OUTPUT VOLTAGE (V) LTC1643AL LTC1643AL-1/LTC1643AH MIN TYP MAX ≤ 70°C 2.8 2.9 3.0 ● A ≤ 85°C ● 2.75 2.9 3.0 A ≤ ...
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... LTC1643AL LTC1643AL-1/LTC1643AH 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 – 100 125 TEMPERATURE (°C) 1643A G04 Power Good Threshold Voltage vs Temperature (12V ) OUT 11.14 11.12 11.10 11.08 11.06 11.04 –50 –25 ...
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... LT1643A G17 12V Undervoltage Lockout IN vs Temperature 9.515 9.510 9.505 9.500 9.495 9.490 9.485 50 100 125 –50 – TEMPERATURE (°C) 1643A G20 LTC1643AL 12V Supply Current IN vs Temperature 3.72 3.70 3.68 3.66 3.64 3.62 –50 – 100 125 TEMPERATURE (°C) 1643A G15 3V ...
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... TIMER. Current limit faults will be ignored until the voltage at the TIMER pin rises to with a foldback within 0.9V of 12V ON/ON (Pin 5): Digital Input.The LTC1643AL/LTC1643AL-1 have an active low enable, ON, and the LTC1643AH has an active high enable, ON. When the ON pin is pulled high or 3V ...
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... FAULT pin is released, the state of the chip will be determined by the ON pin. PWRGD (Pin 7): Open-Drain Digital Power-Good Output. PWRGD remains low while V 12VOUT ≥ 4.75V and V ≤ – 10.8V. The LTC1643AL-1 V 5VOUT EEOUT has the power good comparators connected to the 12V and V ...
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... The chip also protects the PCI supplies from shorts and monitors the supply voltages. The LTC1643AH is designed for motherboard applica- tions, while the LTC1643AL/LTC1643AL-1 are designed for CompactPCI applications where the chip resides on the plug-in board. and 12V ...
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... W U Some ±12V supplies in CompactPCI applications are not well regulated and can violate the tolerance specification. For these applications, the LTC1643AL-1 should be used because the PWRGD signal does not depend on ±12V outputs. Power-Up Sequence The power supplies are controlled by placing external N-channel pass transistors in the 3.3V and 5V power paths, and internal pass transistors for the 12V and – ...
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... LTC1643AL LTC1643AL-1/LTC1643AH 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 5V/DIV FAULT 10V/DIV PWRGD 10V/DIV 10ms/DIV Figure 2. Normal Power-Up Sequence 0.007Ω IRF7413 ...
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... CompactPCI Application The LTC1643AL is designed for hot swapping CompactPCI boards. The typical application is shown in Figure 7. The 3.3V, 5V, 12V and –12V inputs to the LTC1643AL come from the medium length power pins. The long 3.3V, 5V and V(I/O) pins power up the pull-up resistors, bus precharge ...
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... Figure 5. Short Circuit on 5V Followed by Circuit Breaker Reset R1 Q1 0.007Ω IRF7413 20Ω 0.005Ω IRF7413 1µ 1µF 20Ω 10Ω GATE SENSE OUT IN SENSE LTC1643AL Figure 6. Delay in the Current Limit Loop 20ms/DIV 10Ω 3.3V 7.6A R7 100Ω 0.047µF 5V OUT 1643A F06 1643A F05 1643afb ...
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... The power good comparators on the 12V The V EEIN still operate normally if a – 12V However, 12V is still required at the 12V to function. Refer to Figure 10 for a typical LTC1643AL-1 application circuit. LTC1643AL LTC1643AL-1/LTC1643AH ...
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... LTC1643AL LTC1643AL-1/LTC1643AH U U APPLICATIONS INFORMATION Increasing 12V and – 12V Current Capability for PCI Applications The internal switches of the LTC1643A are designed for up to 500mA loads on 12V and 200mA on –12V. If more current is needed, then the circuits in Figure 8 can be used. For the 12V supply, P-channel transistor Q4 is placed in parallel with the internal switch ...
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... GATE SENSE SENSE GND 12V IN V EEIN ON LTC1643AH FAULT PWRGD Figure 9. System Without 3.3V Supply LTC1643AL LTC1643AL-1/LTC1643AH .189 – .196* (4.801 – 4.978) .009 (0.229 REF .150 – .157** (3.810 – 3.988 .004 – .0098 (0.102 – 0.249) .0250 (0.635) BSC ...
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... IRF7413 10Ω 10Ω GATE SENSE OUT IN SENSE 1 12V EEIN 5 ON LTC1643AL-1 6 FAULT 7 PWRGD TIMER GND 0.1µF LOCAL_PCI_RESET# R14 10Ω, 5% DATA LINE EXAMPLE DATA BUS www.linear.com ● 3.3V 7.6A R5 100Ω 0.047µF 5V OUT 16 12V NC OUT EEOUT PRECHARGE OUT 1V ± ...