LTC4211CMS8 Linear Technology, LTC4211CMS8 Datasheet
LTC4211CMS8
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LTC4211CMS8 Summary of contents
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... Zener diode clamp. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners SENSE 0.007Ω ...
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... FB MS8 PACKAGE 8-LEAD PLASTIC MSOP = 125°C, θ 200°C/ W JMAX JA ORDER PART MS8 PART NUMBER MARKING LTC4211CMS8 LTSC LTC4211IMS8 LTSD The ● denotes specifications which apply over the full operating = 25° 5V, unless otherwise noted. (Note CONDITIONS FB = High High, TIMER = Low ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are T SYMBOL PARAMETER I Normal GATE Pull-Down Current GATEDOWN Fast GATE Pull-Down Current ∆V External N-Channel Gate Drive GATE V GATE Overvoltage Lockout Threshold GATEOV V FB Voltage Threshold FB ∆V FB Threshold ...
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LTC4211 W U TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Supply Voltage 4 25°C A 3.5 3.0 2.5 2.0 1.5 1.0 0 SUPPLY VOLTAGE (V) ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS GATE Output Source Current vs Supply Voltage 25° SUPPLY VOLTAGE (V) 4211 ...
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LTC4211 W U TYPICAL PERFOR A CE CHARACTERISTICS FILTER Threshold vs Temperature 1. 1.35 1.30 HIGH THRESHOLD 1.25 1.20 LOW THRESHOLD 1.15 1.10 75 100 125 –75 –50 – 150 TEMPERATURE (°C) 4211 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS TIMER Pull-Up Current vs Supply Voltage 2. 25°C A 2.20 2.10 2.00 1.90 1.80 1. SUPPLY VOLTAGE (V) 4211 G28 ...
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LTC4211 W U TYPICAL PERFOR A CE CHARACTERISTICS V (FAST COMP Temperature 170 165 160 155 150 145 140 135 130 25 50 –75 – 50 – 100 125 150 TEMPERATURE (°C) ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS FAULT Pin Low to GATE Discharging Time vs Supply Voltage 4 25°C A 4.0 3.5 3.0 2.5 2.0 1 SUPPLY ...
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LTC4211 CTIO S (8-Lead Package/10-Lead Package) RESET (Pin 1/Pin 1): An open-drain N-channel MOSFET whose source connects to GND (Pin 4/Pin 5). This pin pulls low if the voltage at the FB pin (Pin 5/Pin ...
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CTIO S (8-Lead Package/10-Lead Package) FAULT (Not available on S8/MS8, Pin 10 MS): FAULT is both an input and an output. Connected to this pin are an analog comparator (COMP6) and an open-drain N-chan- nel ...
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LTC4211 U OPERATIO HOT CIRCUIT INSERTION When circuit boards are inserted into or removed from live backplanes, the supply bypass capacitors can draw huge transient currents from the backplane power bus as they charge. The transient current can cause permanent ...
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U OPERATIO UNDERVOLTAGE LOCKOUT The LTC4211’s power-on reset circuit initializes the start- up procedure and ensures the chip is in the proper state if the input supply voltage is too low. If the supply voltage falls below 2.18V, the LTC4211 ...
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LTC4211 U OPERATIO Table TIMER TIMER C TIMER 0.0033µF 0.0047µF 0.0068µF 0.0082µF 0.01µF 0.015µF 0.022µF 0.033µF 0.047µF 0.068µF 0.082µF 0.1µF 0.15µF 0.22µF 0.33µF CHECK FOR GATE < 0. ...
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U OPERATIO a start-up check to make sure the supply voltage is above its 2.3V UVLO threshold (see Time Point 1). If the input supply voltage is valid, the gate of the external pass transistor is pulled to ground by ...
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LTC4211 U OPERATIO In this fashion, the inrush current is controlled and C is charged up slowly during the soft-start cycle. The timing diagram in Figure 6 illustrates the operation of the LTC4211 in a normal power-up sequence with limited ...
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U OPERATIO or by actively limiting the inrush current. The LTC4211 uses GATE voltage slew rate limiting when C and/or the inrush current limit is set high. If GATE voltage slew rate control is preferred with large C capacitor (C ...
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LTC4211 U OPERATIO TIMER GATE V OUT RESET V – SENSE FAULT Figure 8. Output Short Circuit Causes Fast Comparator to Trip the Circuit Breaker 18 FAST COMPARATOR ARMED SLOW COMPARATOR ARMED CIRCUIT ...
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U OPERATIO TIMER GATE V OUT RESET V – SENSE FILTER FAULT Figure 9. Mild Overcurrent Slow Comparator Trips the Circuit Breaker After Filter Programming Period FAST COMPARATOR ARMED SLOW COMPARATOR ARMED OVER ...
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LTC4211 U OPERATIO TIMER GATE V OUT RESET V – SENSE FILTER FAULT Figure 10. Power-Up in Overcurrent, Slow Comparator Trips the Circuit Breaker start-up sequence where the LTC4211 is powered up into ...
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U OPERATIO Table SLOWCOMP FILTER C FILTER 100pF 220pF 330pF 470pF 680pF 820pF 1000pF SENSE RESISTOR CONSIDERATIONS The fault current level at which the LTC4211’s internal electronic circuit breaker trips is determined by a sense resistor ...
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LTC4211 U OPERATIO The maximum load current that trips the circuit breaker is given in Equation 12 MAX ( ) = = I TRIP MAX ( ) R R SENSE MIN ( ) SENSE MIN where ⎡ = ...
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U OPERATIO The R of the external pass transistor should be low DS(ON) to make its drain-source voltage ( 2.5V RSENSE error at the output voltage. ...
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LTC4211 U U APPLICATIO S I FOR ATIO BACKPLANE PCB EDGE CONNECTOR CONNECTOR (FEMALE) (MALE RESET Figure 13. Hot Swap Controller On Daughter Board (Staggered Pin Connections Z1* 10Ω ...
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U U APPLICATIO S I FOR ATIO BACKPLANE PCB EDGE CONNECTOR CONNECTOR (FEMALE) (MALE) LONG SHORT SHORT ON/OFF LONG GND ZZ1 = 1SMA10A OR SMAJ10A M2: 2N7002LT1 * OPTIONAL BACKPLANE PCB EDGE CONNECTOR CONNECTOR LAST BLADE OR ...
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LTC4211 U U APPLICATIO S I FOR ATIO 12V Hot Swap Application Figure 17 shows a 12V, 3A hot swap application circuit. The resistor divider R1/R2 programs the undervoltage lockout externally and allows the system to start up after V ...
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U U APPLICATIO S I FOR ATIO 1 ON/FAULT V CC TIMER GATE V OUT RESET V – SENSE FILTER t OFF t 2 DUTY CYCLE = (t FILTER OFF ...
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LTC4211 U U APPLICATIO S I FOR ATIO BACKPLANE PCB EDGE CONNECTOR CONNECTOR (FEMALE) (MALE) LONG 3.3V Z1* LONG 5V Z2* SHORT RESET SHORT ON R10 10k LONG GND voltage side of the MOSFET switch. An abrupt connection, produced by ...
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U U APPLICATIO S I FOR ATIO CURRENT FLOW TO LOAD SENSE RESISTOR Z1* TRANSIENT SNUBBER VOLTAGE NETWORK SUPPRESSOR Figure 22. Recommended Layout for LTC4211 Protection Devices SENSE D ...
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LTC4211 U U APPLICATIO S I FOR ATIO SUPPLY OVERVOLTAGE DETECTION/ PROTECTION USING FILTER PIN In addition to using external protection devices around the LTC4211 for large scale transient protection, low power Zener diodes can be used with the LTC4211’s ...
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U U APPLICATIO S I FOR ATIO OVERVOLTAGE TIMER GATE V OUT RESET >V – 80mV REF FILTER FAULT FAULT IS PULLED LOW (BUT NOT LATCHED) DUE TO A START-UP OVERVOLTAGE PROBLEM FAULT is ...
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LTC4211 U U APPLICATIO S I FOR ATIO BACKPLANE PCB EDGE CONNECTOR CONNECTOR (FEMALE) (MALE) LONG 5V SHORT FAULT SHORT RESET SHORT ON/OFF LONG GND Figure 25. LTC4211MS Low Side Overvoltage Protection Implementation OVERVOLTAGE SENSED BY FILTER PIN 1 2 ...
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U U APPLICATIO S I FOR ATIO ramped up to its nominal operating value. After Time Point 5, a supply voltage fault occurs at the load and the Zener diode begins to conduct, causing V crease. At Time Point 6A, ...
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LTC4211 U APPE DIX Table 4 lists some current sense resistors that can be used with the circuit breaker. Table 5 lists some power MOSFETs that are available. Table 6 lists the web sites of several Table 4. Sense Resistor ...
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... 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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... Operates from –10V to –80V 8-Pin, Operates from 9V to 80V, Latch-Off/Auto Retry 16-Pin, Overvoltage Protection to 33V 16-Pin, 3.3V, 5V and ±12V, 1V Precharge, PCI Reset Logic 8-Pin, 16-Pin, Operates from 2.7V to 16.5V Operates from 1.7V to 16.5V LT 0906 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2006 4211fa ...