LTC1647-2IS8#TR Linear Technology, LTC1647-2IS8#TR Datasheet
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LTC1647-2IS8#TR
Specifications of LTC1647-2IS8#TR
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LTC1647-2IS8#TR Summary of contents
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... A programmable electronic circuit breaker protects against overloads and shorts. The ON pins are used to control board power or clear a fault. The LTC1647 dual Hot Swap controller with a common V CC 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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... LTC1647-1CS8#PBF LTC1647-1CS8#TRPBF LTC1647-1IS8#PBF LTC1647-1IS8#TRPBF LTC1647-2CS8#PBF LTC1647-2CS8#TRPBF LTC1647-2IS8#PBF LTC1647-2IS8#TRPBF LTC1647-3CGN#PBF LTC1647-3CGN#TRPBF LTC1647-3IGN#PBF LTC1647-3IGN#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifications, go to: ...
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... The GATE capacitance must be < 0.15μF at maximum V pin clamp voltage is desired, use an external Zener diode. Note 4: The total supply current I connected internally (LTC1647-1, LTC1647-2) or externally (LTC1647-3). Note 5: The individual supply current I The lower of the two supplies, V current. The higher supply will carry the additional supply current of the charge pump and the bias generator beside its channel’ ...
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... LTC1647-2/LTC1647-3 PIN 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 FAULT1 2 6 (Internally Tied Together) 7 ON1 and FAULT2 3 8 (Internally Tied Together) 4 GND The ONX/FAULTX must be connected to a driver via a resistor if the autoretry feature is being used ...
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... CC1 CC2 (V) CC 1647-1/2/3 G06 (V – Temperature GATE1 CC1 12V CC1 15V CC1 CC1 CC1 T = 25°C A (LTC1647- (V) CC2 1647-1/2/3 G09 GATE Output Source Current vs Temperature CC1 CC2 –75 –50 – 100 125 150 TEMPERATURE (°C) 1647-1/2/3 G12 1647fa 5 ...
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... LTC1647-1/ LTC1647-2/LTC1647-3 TYPICAL PERFORMANCE CHARACTERISTICS GATE Output Sink Current 100 T = 25° (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 Undervoltage Lockout Threshold vs Temperature 2.6 2.5 RISING EDGE 2.4 2 ...
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... I = 5mA OL 0.8 0.6 0 1mA OL 0.2 0 –75 –50 – 100 125 150 TEMPERATURE (°C) 1647-1/2/3 G23 Circuit Breaker Reset Time 25° (V) CC 1647-1/2/3 G26 LTC1647- FAULT CC 1 25°C A 0.8 0.6 0.4 0 (V) CC 1647-1/2/3 G24 Circuit Breaker Reset Time vs Temperature 12V ...
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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 are internally connected CC1 CC2 together. GND: Chip Ground. ON1: Channel 1 ON Input. The threshold at the ON1 pin is set at 1 ...
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... PUMP CHANNEL TWO (DUPLICATE OF CHANNEL ONE) LTC1647-2 CHANNEL ONE + – + 50μs FILTER – 2.45V UVL FAULT CHARGE 1.21V CP PUMP CHANNEL TWO (DUPLICATE OF CHANNEL ONE) LTC1647-1/ LTC1647-2/LTC1647-3 CP 10μA 6 GATE1 50μA 5 GATE2 1647-1/2/3 BD1 CP 10μA 6 GATE1 50μA 5 GATE2 1647-1/2/3 BD2 1647fa 9 ...
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... PUMP SELECTION CHANNEL TWO (DUPLICATE OF CHANNEL ONE) Electronic Circuit Breaker Each channel of the LTC1647 features an electronic circuit CC1 breaker to protect against excessive load current and short- circuits. Load current is monitored by sense resistor R1 as shown in Figure 1. The circuit breaker threshold, V 50mV and it exhibits a response time, t 300ns ...
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... SENSE pins are highly CC = – R3•C3•ln[1 – (V /R1 – I )/( specified 10V) and logic-level DS(ON) GS specified 5V). The absolute DS(ON typically 20V for standard GS rating. The LTC1647 GS is illustrated in the Typical CC as shown in Figure 4. For OUT TRIP LOAD – 1647fa 11 ...
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... LOGIC) FAULT 0.1μF RAMP-DOWN V CC DISCHARGES 1647-1/2/3 F05 , or is pulled high before CC CC (Figure 6). Once LKO about 700mV below V CC – the LTC1647 enters UVLO LKO LKH V GATE V GATE DUE TO V RAMP-UP FAST RAMP-DOWN SLOPE = 10μA/C1 AT UNDERVOLTAGE LOCKOUT V OUT C ...
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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 present. An abrupt connection, produced by plugging a ...
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... The two Hot Swap channels of the LTC1647 are ideally suited for V power control in portable computers. ID Figure 13 shows an application using the LTC1647-2 on the system side of the device bay interface (1394 PHY and/or USB). The controller detects the presence of a peripheral 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 ...
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... V SENSE GATE LTC1647-3 FAULT 8 GND 8a. HOT SWAP CONTROLLER ON MOTHERBOARD STAGGERED PCB EDGE CONNECTOR SENSE LTC1647-3 FAULT 8 GND 8b. HOT SWAP CONTROLLER ON DAUGHTERBOARD Figure 8. Staggered Pins Connection LTC1647-1/ LTC1647-2/LTC1647-3 STAGGERED PCB EDGE CONNECTOR V OUT + C LOAD Q1 V OUT + C LOAD GATE 1647-1/2/3 F08 1647fa 15 ...
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... REQUIRED FOR V 24V 0V 1μs/DIV 9a. Undamped V Waveform (48” Leads IRF7413 0.01Ω R2 10Ω POWER SCOPE LEADS PROBE LTC1647 >10V CC 24V 1647-1/2/3 F09a 9b. Undamped V Figure 9. Ring Experiment V OUT + C LOAD C1 *D1 10nF DDZ23 1647-1/2/3 F09 0V 1μs/DIV 1647-1/2/3 F09b Waveform (8” Leads) ...
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... LTC1647 1647-1/2/3 F10 Figure 10. Transient Suppressor Clamp Q1 R1 IRF7413 0.01Ω R3 10Ω C1 0.1μF LTC1647 > 10V CC 1647-1/2/3 F11a 11b. V Figure 11. Snubber “Fixes” LTC1647-1/ LTC1647-2/LTC1647-3 12V 0V 1μs/DIV 1647-1/2/3 F10a V Waveform Clamped Transient Suppressor V OUT + C LOAD R2 10Ω C1 *D1 10nF ...
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... V Short-Circuit Supply Current Glitch without Any Limiting CC 18 SUPPLY GLITCH IRF7413 2μH 0.01Ω R2 10Ω 100μF C1 10nF LTC1647 > 10V CC Figure 12. Supply Glitch GATE OF MOSFET V SHORT-CIRCUIT CC SUPPLY CURRENT 1647-1/2/3 F12a 12b. V *D1 DDZ23 1647-1/2/3 F12 5V/DIV V CC 5V/DIV 10A/DIV 5μ ...
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... GATE1 ON2 t9 t10 FAULT 2 WAVEFORM SHOWN WITHOUT C6 FAULT2 GATE2 Power Controller with Fault Status and Retry Sequence ID LTC1647-1/ LTC1647-2/LTC1647-3 DEVICE #1 + 1394 PHY R3 R4** AND/OR LOAD USB PORT C1 10nF * C IS USER-SELECTED BASED LOAD ON THE DEVICE REQUIREMENTS ** R3, R4, R7 AND R8 ARE OPTIONAL DISCHARGE RESISTORS WHEN DEVICES ARE POWERED-OFF ...
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... LTC1647-1/ LTC1647-2/LTC1647-3 PACKAGE DESCRIPTION .254 MIN .0165 ±.0015 RECOMMENDED SOLDER PAD LAYOUT .007 – .0098 (0.178 – 0.249) .016 – .050 (0.406 – 1.270) NOTE: 1. CONTROLLING DIMENSION: INCHES 2. DIMENSIONS ARE IN (MILLIMETERS) 3. DRAWING NOT TO SCALE .050 BSC .245 MIN .030 ±.005 ...
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... Revised Figure 14 in Typical Applications and updated Related Parts list 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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC1647-1/ LTC1647-2/LTC1647-3 PAGE NUMBER 11, 12, 15 ...
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... LTC1647-2/LTC1647-3 TYPICAL APPLICATION 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’ ...