ltc1421isw-trpbf Linear Technology Corporation, ltc1421isw-trpbf Datasheet
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ltc1421isw-trpbf
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ltc1421isw-trpbf Summary of contents
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... Controls Supply Voltages from 3V to 12V Connection Inputs Detect Board Insertion or Removal Undervoltage Lockout Power-On Reset Input U APPLICATIO S Hot Board Insertion Electronic Circuit Breaker , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. U TYPICAL APPLICATIO ...
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... SETLO LTC1421CSW 4 21 GATELO LTC1421CG-2 OUTLO LTC1421CSW-2 CCHI LTC1421IG 7 18 SETHI LTC1421ISW 8 17 GATEHI LTC1421IG-2 OUTHI LTC1421ISW-2.5 15 COMPOUT – 14 COMP + 13 COMP SW PACKAGE 24-LEAD PLASTIC SO = 125 C, = 100 C/W ( 125 C/W (SW unless otherwise noted (Note 2). MIN TYP MAX 1.5 3 0.6 1 2.28 2.45 2.60 100 1 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER I RAMP Pin Output Current RAMP I Charge Pump Output Current CP V GATEHI N-Channel Gate Drive GATEHI V GATELO N-Channel Gate Drive GATELO V Auxiliary V Output Voltage ...
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LTC1421/LTC1421-2 TYPICAL PERFORMANCE CHARACTERISTICS Reference Voltage vs Temperature 1.238 CCLO V = 12V CCHI 1.236 1.234 1.232 1.230 1.228 1.226 1.224 – 50 – 100 125 TEMPERATURE ( C) 1421 ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS CPON Voltage vs Source Current (Charge Pump On – 0.5 – 1.0 – 1.5 SOURCE CURRENT (mA PIN FUNCTIONS CON1 (Pin 1): TTL Level Input ...
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LTC1421/LTC1421-2 PIN FUNCTIONS RAMP (Pin 10): Analog Power-Up Ramp Control Pin. By connecting an external capacitor between the RAMP and GATEHI, a positive linear voltage ramp on GATEHI and GATELO is generated on power-up with a slope ...
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W BLOCK DIAGRAM CCLO CC 24 AUXV CC 50mV CPON FAULT 1 CON1 2 CON2 3 POR 5 DISABLE 12 GND U W SWITCHI WAVEFOR S ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION Hot Circuit Insertion When circuit boards are inserted into a live backplane, the supply bypass capacitors on the board can draw huge transient currents from the backplane power bus as they charge up. The transient ...
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U U APPLICATIONS INFORMATION PWRGD and RESET The LTC1421 uses a 1.232V bandgap reference, internal resistive divider and a precision voltage comparator to monitor V (Figure 6). OUTLO The reset threshold voltage for V OUTLO the FB pin connection as ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION Figure 8c shows how the comparator can be used to generate a reset when the 12V supply (V below 10.8V. The 5V supply (V OUTLO reset when it dips below 4.65V. When the 12V supply ...
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U U APPLICATIONS INFORMATION is connected between REF (Pin 8) and the negative supply and the trip point of Comparator 2 set to GND. Soft Reset Generation A soft reset that doesn’t cycle the supply voltage can be generated externally ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION When V collapses, there is enough energy stored on CCLO the 1 F capacitor connected to AUXV discharge circuitry alive long enough to fully turn off the external N-channels. Power N-Channel Selection The R of ...
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U U APPLICATIONS INFORMATION can usually be prevented by using logic that does not include the clamping diodes such as the QSI 74FCTT family from Quality Semiconductor using a data bus switch such as the 10-bit QS3384 QuickSwitch ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION When CON1 and CON2 are both forced to ground for more than 20ms, the LTC1421 assumes that the board is fully connected to the host and power-up can begin. When V and V exceed the ...
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U U APPLICATIONS INFORMATION time point 2). Pulses less than 20ms on POR are ignored. CPON goes low. Both GATEHI and GATELO will be actively pulled down to GND. When V its reset threshold voltage, PWRGD will immediately pull low ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION Board Removal Timing When the board is removed from the host, the sequence happens in reverse (Figure 17). Since CON1 and CON2 are the shortest pins, they break connection first and are internally pulled high ...
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U U APPLICATIONS INFORMATION 5V Only Applications The LTC1421 may be used in 5V only applications as shown in Figure 18. A soft reset can be generated from the backplane via an open-collector inverter driving the FB (Pin 11) or ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION module. The ground pin for the LTC1421 is connected to – 48V; Zener diode D1 and resistor R1 provide the positive supply for the chip. Bypass capacitor C4 is protected against inrush current by P-channel ...
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U U APPLICATIONS INFORMATION W U CONNECTOR STAGGERED LTC1421/LTC1421-2.5 19 ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION – 48V 0.1 F – 48V BACKPLANE PC BOARD 24V R1 5.1k 1/ 2.2 F 5.1V 25V FAULT 3 POR 1 S1 BACKPLANE PC BOARD Figure ...
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U U APPLICATIONS INFORMATION W U CONNECTOR STAGGERED LTC1421/LTC1421-2.5 21 ...
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LTC1421/LTC1421-2 APPLICATIONS INFORMATION – 48V BACKPLANE PC BOARD 5V BACKPLANE PC BOARD Figure 25. Hot Swappable 5V Supply with Overvoltage Protection ...
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... DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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. ...
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... IRF7413 1 2 3.3V 11.5A CIRCUIT BREAKER 10A CIRCUIT BREAKER R6 100 1% 1/16W R8 5.62k 1% 1/16W GND LOGIC RST # R7 130k TP0610T 25V – 12V NO CIRCUIT BREAKER Q2 1421 F27 1/2 IRF7101 PCI PERIPHERAL 1421fc LT/LCG 0301 2K REV C • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1996 ...