LM5068MM-3/NOPB National Semiconductor, LM5068MM-3/NOPB Datasheet
LM5068MM-3/NOPB
Specifications of LM5068MM-3/NOPB
LM5068MM-3TR
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LM5068MM-3/NOPB Summary of contents
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... LM5068-2 and -4 continuously re-try at intervals set by a programmable timer. The LM5068 is available in a MSOP-8 package. Typical Application © 2004 National Semiconductor Corporation Features n Safe module insertion and removal from live backplanes n In-rush current limiting for safe board insertion into live ...
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Connection Diagram Pin Description PIN NAME 1 PWRGD Open Drain Power Good indicator 2 OV Line Over-Voltage Shutdown 3 UV Line Under-Voltage Shutdown 4 V Negative Supply Voltage Input EE 5 SENSE Current Sense Input 6 GATE N-Channel MOSFET Gate ...
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... LM5068MM-2/MMX-2 Auto Re-try LM5068MM-3/MMX-3 Latch Off LM5068MM-4/MMX-4 Auto Re-try Ordering Information Order Number Package Marking LM5068MM-1 LM5068MMX-1 LM5068MM-2 LM5068MMX-2 LM5068MM-3 LM5068MMX-3 LM5068MM-4 LM5068MMX-4 Power Good Polarity Active HIGH Active HIGH Active LOW Active LOW NSC Package Drawing S66B S66B S67B S67B ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications PWRGD (PWRGD SENSE (SENSE UV/OV (Clamped) (UV/ All Other Inputs Electrical Characteristics Specifications in standard typeface are for T perature range. Unless otherwise noted V ...
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Electrical Characteristics Specifications in standard typeface are for T perature range. Unless otherwise noted V Symbol Parameter Gate Drive V Saturation Gate Drive Voltage G V Gate Low Threshold GLT I Gate Pin Current (Sourcing) GATE Gate Pin Current (Sinking) ...
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Block Diagram www.national.com 6 20078603 ...
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Typical Performance Characteristics I vs Temperature IN V Under-Voltage Shutdown (V DD UVS Under-Voltage Comparator Threshold (V Over-Voltage Comparator Threshold (V Temperature 20078632 V Under-Voltage Shutdown Hysteresis ( Temperature 20078634 ) and Under-Voltage Comparator ...
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Typical Performance Characteristics Over-Voltage Comparator Threshold Hysteresis Current Sink ( Temperature OVHCS Circuit Breaker Current Limit Voltage (V Temperature Fast Discharge Current Limit Voltage (V Temperature www.national.com (Continued) UV Comparator Delay (t (t OVCD 20078638 ) vs CB ...
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Typical Performance Characteristics Timer Low Voltage Threshold (V TLVT Timer On (Circuit Breaker, Sourcing) vs Temperature Saturation Gate Drive Voltage ( Temperature (48V) G (Continued Temperature Timer On (Initial Cycle, Sourcing) vs Temperature 20078644 Timer Off ...
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Typical Performance Characteristics Gate Pin Current (Sourcing) (I GATE Gate Voltage at onset of PWRGD (V www.national.com (Continued Temperature PWRGD Low Voltage (V 20078652 ) vs Temperature PGV 20078656 Temperature PGLV 20078655 ...
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Function Description The LM5068 is designed to facilitate the insertion and re- moval of circuit cards into live backplanes in a controlled manner. Because the supply bypass capacitors on the circuit card can draw large transient currents critical ...
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Current Control (Continued) conditions. The voltage drop across the sense resistor (R is monitored at the SENSE pin. The over-current protection functions are determined through the following three distinct thresholds at the SENSE pin: 1. Circuit Breaker (CB) threshold (typically ...
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UV and OV Thresholds and Voltage Divider Selection for R1, R2, and R3 (Continued) Hysteresis is necessary to prevent a possible “chattering” condition when the controller enables or disables the exter- nal MOSFET. The change in line current interacts with ...
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Sense Resistor (R ), Timer s Capacitor (C ) and N-Channel T Mosfet (Q1) Selection Applying Equation (5) and Equation (7) to Equation (2) gives the TIMER capacitor value of: Finally, the SOA curves of a prospective MOSFET are checked ...
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Timing Diagrams Assuming all of the initial conditions are met, the power-up sequence starts with Timer capacitor ( charged with 6µA current source quickly discharge to V (1V). At time point (2) the 60µA ...
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Timing Diagrams (Continued) UV drops below UV HIGH (time point 1) puts the controller into a disabled mode. Later, UV increases over the UV LOW threshold (time point 3), which initiates a system power-up sequence. www.national.com FIGURE 6. Under-Voltage Timing ...
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Timing Diagrams (Continued) During normal operation, if the OV pin exceeds OV HIGH, as shown at time point 1 in the above diagram, the TIMER status is unaffected. The GATE and PWRGD ( for LM5068-1 & -2) pins are pulled ...
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Timing Diagrams (Continued) The above timing waveform shows the circuit breaker cur- rent limit fault behavior. The timer capacitor is charged with 240µA when the SENSE pin exceeds V drops below V before the TIMER reaches V CB www.national.com FIGURE ...
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Timing Diagrams (Continued) The above diagram shows analog current limit behavior when the SENSE pin voltage exceeds V time, which activates the Analog Current Limit but never reaches the fault timer threshold. At that time the GATE is regulated by ...
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Timing Diagrams (Continued) In case of a severe fault (for example sudden short-circuit of the output load) the SENSE pin exceeds the V and GATE immediately pulls down until the Active Current Limit loop establishes control of the current in ...
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Timing Diagrams (Continued) FIGURE 11. Shutdown Cooling Timing Behavior Figure 11 shows the timer behavior for LM5068-2, -4 during fault re-try time. During normal operation, whenever the SENSE pin exceeds the 50mV, circuit breaker fault limit, the timer capacitor begins ...
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Evaluation Board Schematic PART VALUE C1 NOT USED C2 NOT USED C3 0.022uF/ 50V C4 0.33uF / 50V C5 100uF / 100V C6 0.1uF / 100V F1 10A FUSE J1 PCB terminal Blocks/ 10A J2 PCB terminal Blocks/ 10A Q1 ...
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... Evaluation Board Schematic PART VALUE U1 LM5068 (Continued) PACKAGE DESCRIPTION MSOP-8 National Semiconductor 23 PART NUMBER LM5068 20078660 20078661 www.national.com ...
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www.national.com 24 20078662 20078673 ...
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25 20078674 www.national.com ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...