LTC4214-2 Linear Technology, LTC4214-2 Datasheet
LTC4214-2
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LTC4214-2 Summary of contents
Page 1
... A power good status output can enable a power module at start-up or disable it if the circuit breaker trips. The LTC4214-1 latches off after a circuit breaker fault times out. The LTC4214-2 provides automatic retry after a fault. The LTC4214 is available in the 10-pin MSOP package. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... Current into DRAIN Pin (100 s Pulse) ................... 5mA Maximum Junction Temperature .......................... 125 C Operating Temperature Range LTC4214-1C/LTC4214-2C ....................... LTC4214-1I/LTC4214-2I ................... – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T ...
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... Note 2: All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to V specified 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 125 (V) IN 4214 G01 LTC4214-1/LTC4214-2 MIN TYP –15 0.1 3 1.7 –5 = 2.2V TMR = 2.2V 28 TMR –40 –200 5 = 2.2V TMR = DRN 1.109 1.232 0.1 3.5 4.2 0.2 –30 –50 130 0 ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com W TYPICAL PERFOR A CE CHARACTERISTICS otherwise specified. Undervoltage Lockout Hysteresis V vs Temperature LKH 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 –55 –35 – 105 25 65 TEMPERATURE ( C) Fast Current Limit Voltage V vs Temperature FCL 300 V = 12V IN 275 250 225 200 175 150 –55 –35 – ...
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... TEMPERATURE ( C) 4214 G16 V vs Temperature UVHST 0. 12V IN 0.27 0.26 0.25 0.24 0.23 0.22 125 –55 –35 – TEMPERATURE ( C) 4214 G19 LTC4214-1/LTC4214-2 All voltages are referenced to V Unless EE I (FCL, Sinking) GATE vs Temperature 400 V UV/OV = 2.5V 350 TIMER = 0.15V EE 300 V 250 200 150 100 50 0 –55 – ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com W TYPICAL PERFOR A CE CHARACTERISTICS otherwise specified Temperature OVHST 0. 12V IN 0.17 0.16 0.15 0.14 0.13 0.12 85 105 –55 –35 – TEMPERATURE ( C) TIMER Threshold vs Temperature 4 12V IN 3.5 3.0 V TMRH 2.5 2.0 V TMRL 1.5 1.0 0.5 85 105 –55 –35 – TEMPERATURE ( C) I (Circuit Breaker, Sourcing) TMR vs Temperature ...
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... IN SS PIN FLOATING, V RAMPS FROM 0.2V TO 1.4V 150 SS 140 130 120 110 100 105 125 –55 –35 – TEMPERATURE ( C) 4214 G37 LTC4214-1/LTC4214-2 All voltages are referenced to V Unless DRN DRAIN 100 V = 12V 0.1 0.01 0.001 0.0001 0.00001 ...
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... LTC4214-1/LTC4214 CTIO S V (Pin 1): Positive Supply Input. Connect this pin to the IN positive side of the supply via a resistor. An internal undervoltage lockout (UVLO) circuit holds GATE low until the V pin is greater than V ...
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... The charging clears UVLO, IN and discharging currents are 5 A and TIMER ramps , SS < 0.2V, GATEL between its 1.7V and 3V thresholds. At the completion of a shutdown cooling cycle, the LTC4214-2 attempts a start- charges cycle SENSE DRN . In the event that C ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com W BLOCK DIAGRA 2.25V TIMER 1. 69.35k 3.65k – + 1.232V V IN – – + LOGIC – + – ...
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... MOSFET characteristics and nomi- nal design current. One possibility is that the MOSFET will LONG GND SHORT + C LOAD LOAD LONG –12V 4214 F01 LTC4214-1/LTC4214-2 ) voltage is < 50mV ( < 1. GATEL , falls out of range, the start-up cycle IN to less than 1.7V, then ...
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... UV momentarily low or drop- ping the input voltage V old of 4.8V or pulling TIMER momentarily low with a switch. The LTC4214-2 retries after its shutdown cooling cycle. Although short-circuits are the most obvious fault type, several operating conditions may invoke overcurrent pro- tection ...
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... LTC4214 PWRGD DRAIN TIMER GATE SENSE 47nF 1nF 22nF LTC4214-1/LTC4214 OVHI – 2.85V OVHI 0VHST . GND R4 + 100k C L 100 NDS0605 0 PULLDN 10k 475k OUT Q1 IRF7413 R R ...
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... If the SENSE pin detects more than a 50mV drop across R , the TIMER pin charges C S charges to 3V, the GATE pin pulls low and the LTC4214-1 latches off while the LTC4214-2 starts a shutdown cooling is given by: cycle. The LTC4214-1 remains latched off until the UV pin D is momentarily pulsed low or TIMER is momentarily ...
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... SHUTDOWN COOLING CYCLE For the LTC4214-1 (latchoff version), TIMER latches high with pull-up after the circuit breaker fault TIMER reaches 3V. For the LTC4214-2 (automatic retry version), a shutdown cooling cycle begins if TIMER reaches the 3V threshold. TIMER starts with pull-down until it reaches the 1 ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com U U APPLICATIO S I FOR ATIO GATE GATE is pulled low to V under any of the following EE conditions: in UVLO undervoltage condition overvoltage condition, during the initial timing cycle or when the circuit breaker fault times out. When GATE turns on current source charges the MOSFET gate and any associated external capacitance ...
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... INRUSH MIN Maximum short-circuit current limit is calculated using the maximum V I SHORTCIRCUIT MAX The TIMER capacitor C slowest expected charging rate; otherwise TIMER might time out before the load capacitor is fully charged. A value LTC4214-1/LTC4214-2 is calculated and S and C . The circuit breaker ...
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... LTC4214-1/LTC4214 APPLICATIO S I FOR ATIO for C is calculated based on the maximum time it takes the T load capacitor to charge. That time is given by • • CHARGE ( ) I I INRUSH MIN The maximum current flowing in the DRAIN pin is given ...
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... SS control level and the analog current limit loop activates. Between time points 6 and 8, the GATE voltage is servoed, the SENSE voltage is regulated at V (t) (Equation 7) and soft-start limits the slew rate of ACL LTC4214-1/LTC4214-2 CURRENT FLOW CURRENT FLOW FROM LOAD TO –12V BACKPLANE SENSE RESISTOR ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com U U APPLICATIO S I FOR ATIO V CLEARS GND – (–12V) UV/ LKO IN TIMER GATE V GATEL SS SENSE V OUT DRAIN PWRGD Figure 8. System Power-Up Timing (All Waveforms are Referenced to V the load current. If the SENSE voltage (V reaches the V threshold at time point 7, the circuit CB breaker TIMER activates ...
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... GATEL ACL must be satisfied before current. If the SENSE voltage (V V threshold at time point 7, the circuit breaker TIMER CB activates. The TIMER capacitor, C LTC4214-1/LTC4214 < 20 • V AND TIMER < TMRL , CHECK GATE < SENSE < V AND SS < 20 • V ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com U U APPLICATIO S I FOR ATIO ( • current pull-up. As the load capacitor DRN nears full charge, load current begins to decline. At point 8, the load current falls and the SENSE voltage drops below V (t). The analog current limit loop shuts off and the ACL GATE pin ramps further ...
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... V ) ACL OS 20 • • GATE INITIAL TIMING START-UP LTC4214-1/LTC4214-2 (time point 1), an initial timing UVHI threshold. The initial timing cycle restarts, AND TIMER < TMRL , CHECK GATE < SENSE < V AND SS < 20 • V TMRL GATEL CB 10 ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com U U APPLICATIO S I FOR ATIO Overvoltage Timing During normal operation, if the OV pin exceeds V shown at time point 1 of Figure 12, the TIMER and PWRGD status are unaffected. Nevertheless, SS and GATE pull down and the load is disconnected. At time point OVERSHOOTS V ...
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... TIMER capacitor to integrate and reach V is less than 4.2V. If the the LTC4214 shuts down. During shutdown, the LTC4214-1 latches TIMER high with pull-up current source; the LTC4214-2 activates a shutdown cooling cycle. , GATE pulls down TMRH CB TIMES OUT 1 ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com U U APPLICATIO S I FOR ATIO Resetting a Fault Latch (LTC4214-1) The latched circuit breaker fault of LTC4214-1 benefits from long cooling time reset by pulling the UV pin below V – V with a switch. Reset is also accom- UVHI UVHST plished by pulling the V pin momentarily below (V ...
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... SENSE V OUT DRAIN PWRGD CB Figure 15. Shutdown Cooling Timing Behavior of LTC4214-2 (All Waveforms are Referenced and three 5 A charge phases in this shutdown cooling cycle spanning time points 2 and 3. At time point 3, the LTC4214 automatic retry occurs with a start-up cycle. , GATE pulls down ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com U U APPLICATIO S I FOR ATIO Analog Current Limit and Fast Current Limit In Figure 16a, when SENSE exceeds V lated by the analog current limit amplifier loop. When SENSE drops below V , GATE is allowed to pull up. In ACL Figure 16b, when a severe fault occurs, SENSE exceeds ...
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... V ACL SENSE DRNCL V DRAIN DRNL PWRGD (17b) With External C SS LTC4214-1/LTC4214-2 (t) (Equation 7). At time ACL , at time point 7 and the circuit breaker CB (t). The current ACL can cause premature circuit breaker SS (t) may exceed the V potential during ACL CB values is SOA duration may ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com U U APPLICATIO S I FOR ATIO Power Limit Circuit Breaker Figure 18 shows the LTC4214 power limit circuit breaking application. The SENSE pin is modulated by the board supply voltage The zener voltage, V SUPPLY to be the same as the low supply operating voltage 10V ...
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... BSC 4.90 0.152 DETAIL “A” (.193 .006) 0.254 (.010) 0 – 6 TYP 0.53 0.152 (.021 .006) DETAIL “A” SEATING PLANE 0.17 – 0.27 (.007 – .011) TYP LTC4214-1/LTC4214-2 0.497 0.076 (.0196 .003 REF 3.00 0.102 (.118 .004) (NOTE 0.86 1.10 (.034) ( ...
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... LTC4214-1/LTC4214-2 www.DataSheet4U.com TYPICAL APPLICATIO GND 470 100nF GND (SHORT PIN) R1 121k LTC4214 TIMER 32. 47nF 1nF 22nF –12V *M0C207 Z1:SMAJ15A Figure 19. – 12V/2A Hot Swap Controller RELATED PARTS PART NUMBER DESCRIPTION LTC1421 ...