LTC1647-3CGN#PBF Linear Technology, LTC1647-3CGN#PBF Datasheet
LTC1647-3CGN#PBF
Specifications of LTC1647-3CGN#PBF
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LTC1647-3CGN#PBF Summary of contents
Page 1
... The ON pins are used to control board power or clear a fault. The LTC1647 dual Hot Swap controller with a common V SO-8 package. The LTC1647-2 is similar to the LTC1647-1 but combines a fault status flag with automatic retry at the ON pins and is also available in the SO-8 package ...
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... Consult factory for Military grade parts. ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V V Supply Range CC CCX I V Supply Current (Note Supply Current (Note 5, LTC1647-3) CCX CCX V V Undervoltage Lockout LKO CCX V V Undervoltage Lockout Hysteresis LKH CCX V Circuit Breaker Trip Voltage CB ...
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... U PI TABLES LTC1647-1 Pinout PIN DESCRIPTION PIN ON1 6 3 ON2 7 4 GND 8 LTC1647-1 does not have the FAULT status feature. LTC1647-2 Pinout PIN DESCRIPTION PIN ON1 and FAULT 1 6 (Internally Tied Together ON2 and FAULT 2 8 (Internally Tied Together) 4 GND The ONX/FAULT X must be connected to a driver via a resistor if the autoretry feature is being used ...
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... CC2 0 –75 –50 – 100 125 150 TEMPERATURE ( C) 1647-1/2/3 G08 CC1 CC2 15V CC1 V = 12V CC1 CC1 CC1 (V) CC2 1647-1/2/3 G03 GATE CC1 CC2 (V) CC 1647-1/2/3 G06 (V – Temperature GATE1 CC1 12V CC1 15V CC1 CC1 CC1 (LTC1647- (V) CC2 1647-1/2/3 G09 ...
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... GATE Output Sink Current 100 (V) CC 1647-1/2/3 G13 GATE Fast Pull-Down Current vs Temperature CC1 CC2 –75 –50 – 100 125 150 TEMPERATURE ( C) 1647-1/2/3 G16 LTC1647-1/LTC1647-2/LTC1647-3 GATE Output Source Current CC1 CC2 (V) CC 1647-1/2/3 G11 GATE Output Sink Current vs Temperature –75 –50 – ...
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... LTC1647-1/LTC1647-2/LTC1647 TYPICAL PERFOR A CE CHARACTERISTICS Undervoltage Lockout Threshold vs Temperature 2.6 2.5 RISING EDGE 2.4 2.3 FALLING EDGE 2.2 2.1 –75 –50 – 100 125 150 TEMPERATURE ( C) 1647-1/2/3 G19 FAULT 2 1.8 1.6 1.4 1 5mA 1.0 OL 0.8 0.6 0 1mA OL 0 (V) CC 1647-1/2/3 G22 ...
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... CC1 CC2 V (LTC1647-3): Channel 2 Positive Supply Input. See CC2 V for functional description. CC1 V : The Common Positive Supply Input for the LTC1647-1 CC and the LTC1647-2. V and V CC1 CC2 nected together. GND: Chip Ground. ON1: Channel 1 ON Input. The threshold at the ON1 pin is set at 1 ...
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... GND 4 SENSE 2 7 ON2/FAULT LTC1647-1 CHANNEL ONE + – FILTER – 2.45V UVL CHARGE REFERENCE 1.21V CP PUMP CHANNEL TWO (DUPLICATE OF CHANNEL ONE) LTC1647-2 CHANNEL ONE + – FILTER – 2.45V UVL FAULT CHARGE REFERENCE 1.21V CP PUMP CHANNEL TWO (DUPLICATE OF CHANNEL ONE GATE GATE 2 ...
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... If both supplies are connected together (internally for LTC1647-1 and LTC1647-2 or externally for LTC1647-3), the reference and charge pump circuit draw equal current from both pins. Electronic Circuit Breaker Each channel of the LTC1647 features an electronic circuit breaker to protect against excessive load current and LTC1647-1/LTC1647-2/LTC1647-3 LTC1647-3 CHANNEL ONE + – ...
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... MOSFETs. The maximum rating for logic-level MOSFETs is lower and ranges from 8V to 16V depending on the manufacturer and specific part number. Some logic-level MOSFETs have a 20V maximum V LTC1647 is primarily targeted for standard MOSFETs; low )/(I – supply voltage applications should use logic-level ...
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... The LTC1647-2 and LTC1647-3 are designed to allow an automatic reset of the electronic circuit breaker after a fault condition occurs. This is accomplished by pulling the ON/FAULT (LTC1647-2) pin or the ON and FAULT pins tied together (LTC1647-3) high through a resistor, R3, as RAMP-DOWN shown in Figure 7. An autoretry sequence begins if a fault occurs ...
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... The opposite is true for LTC1647 Hot Swap circuits on a daughterboard. In most cases, on the powered side of the MOSFET switch (V ) there is no supply bypass capacitor CC present ...
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... PHY and USB). The controller detects the presence of a periph- eral in each device bay and controls the LTC1647-2. The timing waveform illustrates the following sequence of events: t1, rising out of undervoltage lockout with GATE 1 ramping up; t2, load current fault at R1; t3, circuit breaker resets with R5/C3 delay ...
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... CC R4 FAULT CONNECTOR SENSE GATE LTC1647-3 FAULT 8 GND (a) HOT SWAP CONTROLLER ON MOTHERBOARD STAGGERED PCB EDGE CONNECTOR LTC1647-3 FAULT 8 GND (b) HOT SWAP CONTROLLER ON DAUGHTERBOARD Figure 8. Staggered Pins Connection BACKPLANE STAGGERED PCB EDGE CONNECTOR V OUT + C LOAD Q1 V OUT + C LOAD SENSE GATE 1647-1/2/3 F08 ...
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... U U APPLICATIO S I FOR ATIO 12V 24V 0V 1 s/DIV (a) Undamped V Waveform (48" Leads) LTC1647-1/LTC1647-2/LTC1647 IRF7413 0.01 POWER SCOPE LEADS PROBE + – LTC1647 24V 0V 1647-1/2/3 F09a CC Figure 9. Ring Experiment V OUT + C LOAD 10nF 1647-1/2/3 F09 1 s/DIV 1647-1/2/3 F09b (b) Undamped V CC Waveform (8" Leads) 15 ...
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... Q1 R1 IRF7413 0.01 V OUT + C LOAD R2 D1 10nF LTC1647 1647-1/2/3 F10 Figure 10. Transient Suppressor Clamp R1 0. POWER LEADS C1 0.1 F LTC1647 12V 0V 1647-1/2/3 F11a Figure 11. Snubber “Fixes” 12V 0V 1 s/DIV 1647-1/2/3 F10a V Waveform Clamped Transient Suppressor Q1 IRF7413 V OUT + C LOAD 10nF 1647-1/2/3 F11 ...
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... Supply Current Glitch with 2 H Series Inductor LTC1647-1/LTC1647-2/LTC1647 SUPPLY GLITCH IRF7413 100 F – LTC1647 GATE V 1647-1/2/3 F12a GATE V 1647-1/2/3 F12c Figure 12. Supply Glitch C1 10nF 1647-1/2/3 F12 CC 10 s/DIV 1647-1/2/3 F12b (b) V Supply Glitch CC without Any Limiting CC 10 s/DIV 1647-1/2/3 F12d ...
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... APPLICATIO S I FOR ATIO 3. SUPPLY ON1 FAULT 1 DEVICE BAY CONTROLLER WITH 1394 PHY AND/OR USB ON2 FAULT 2 Figure 13 0.1 1/2 MMDF3N02HD SENSE 1 GATE 1 0 ON1/FAULT 1 LTC1647-2 3 ON2/FAULT 2 4 GND R6 10 SENSE 2 GATE 0 0.1 Q2 1/2 MMDF3N02HD LKO V ON1 t4 t5 FAULT 1 WAVEFORM SHOWN WITH FAULT1 ...
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... 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. LTC1647-1/LTC1647-2/LTC1647-3 U Dimensions in inches (millimeters) unless otherwise noted. ...
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... U TYPICAL APPLICATIO Hot Swapping Two Supplies Two separate supplies can be independently controlled by using the LTC1647-3. In some applications, sequencing between the two power supplies is a requirement. For example, it may be necessary to ramp-up one supply first before allowing the second supply to power-up, as well as requiring that this same supply ramp-down last on power- down. Figure 14’ ...