LTC1647-3 Linear Technology, LTC1647-3 Datasheet
LTC1647-3
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LTC1647-3 Summary of contents
Page 1
... 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. The LTC1647-3 has individual V status pins for each channel and is available in a 16-lead narrow SSOP package. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... 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 ...
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... The GATE capacitance must be < 0. 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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... 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 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 ...
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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 ...
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... CTIO S V (LTC1647-3): Channel 1 Positive Supply Input. The CC1 supply range for normal operation is 2.7V to 16.5V. The supply current typically 1mA. Channel 1’s under- CC1 voltage lockout (UVLO) circuit disables GATE 1 until the supply voltage greater than V CC1 2 ...
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... LTC1647-1/LTC1647-2/LTC1647-3 W BLOCK DIAGRA S + 50mV – SENSE 1 8 1.21V ON1 GND 4 SENSE 2 7 ON2 3 + 50mV – SENSE 1 8 1.21V ON1/FAULT GND 4 SENSE 2 7 ON2/FAULT LTC1647-1 CHANNEL ONE + – FILTER – 2.45V UVL CHARGE REFERENCE 1 ...
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... FAULT APPLICATIO S I FOR ATIO V Selection Circuit CC The LTC1647-3 features separate supply inputs ( for each channel. The reference and charge pump CC2 circuit draw supply current from the higher of the two supplies. An internal V selection circuit detects and CC makes the power connection automatically. This allows a 3V channel to have standard MOSFET gate overdrive when the other channel is 5V ...
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... The added delay is given – R3•C3•ln[1 – (V /R1 – I DELAY 0.01 IRF7413 10k SENSE GATE ON1 LTC1647-3 3 FAULT FAULT 8 GND Figure 1. Supply Control Circuitry – SENSE t FAULT t RESET V GATE V FAULT Figure 2. Current Fault Timing 10 ...
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... GATE pulls down to GND. is equal to OUT Autoretry 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 ...
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... LTC1647-1/LTC1647-2/LTC1647 APPLICATIO S I FOR ATIO pulls the ON pin up. C3 delays GATE turn-on until the voltage at the ON pin exceeds V . The delay time –R3•C3•ln[1–(V – V DELAY IH OL GATE ramps A/C1 until Q1 conducts still shorted to GND, the cycle repeats. The ramp interval ...
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... An inductor ( series with Q1’s source limits the short-circuit di/dt, thereby limiting the peak current and the supply glitch (Figure 12c and 12d). Additional power supply bypass capacitance also reduces the magnitude of the V glitch. CC LTC1647-1/LTC1647-2/LTC1647 Power Controller ID of fully ...
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... 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 R2 C1 ...
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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" ...
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... LTC1647-1/LTC1647-2/LTC1647 APPLICATIO S I FOR ATIO POWER LEADS + 12V – ON SEMICONDUCTOR * 1SMA12CAT3 + 12V – 12V 0V 1 s/DIV (a) V Waveform Damped Snubber (15 , 6.8nF IRF7413 0.01 V OUT + C LOAD R2 D1 10nF LTC1647 1647-1/2/3 F10 Figure 10. Transient Suppressor Clamp R1 0.01 R3 ...
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... U U APPLICATIO S I FOR ATIO 12V 1 s/DIV (a) V Short-Circuit CC Supply Current Glitch without Any Limiting 1 s/DIV (c) V Short-Circuit CC 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 ...
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... LTC1647-1/LTC1647-2/LTC1647 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 ...
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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’ ...