lm25069pmmx-2 National Semiconductor Corporation, lm25069pmmx-2 Datasheet
lm25069pmmx-2
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lm25069pmmx-2 Summary of contents
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... The LM25069-1 latches off after a fault detection, while the LM25069-2 automatically restarts at a fixed duty cycle. The LM25069 is available pin MSOP package. Typical Application © 2009 National Semiconductor Corporation LM25069 Features ■ Operating range: +2.9V to +17V ■ ...
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... Connection Diagram Ordering Information Order Number LM25069PMME-1 LM25069PMM-1 LM25069PMMX-1 LM25069PMME-2 LM25069PMM-2 LM25069PMMX-2 Pin Descriptions Pin # Name Description 1 SENSE Current sense input 2 VIN Positive supply input 3 UVLO/EN Under-voltage lockout 4 OVLO Over-voltage lockout 5 GND Circuit ground 6 TIMER Timing capacitor 7 PWR Power limit set ...
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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. VIN to GND (Note 5) SENSE, OUT, PGD to GND UVLO to GND OVLO to GND VIN to SENSE ...
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... Note 3: OUT bias current (disabled) due to leakage current through an internal 1.0 MΩ resistance from SENSE to VOUT. Note 4: For detailed information on soldering plastic MSOP packages refer to the Packaging Databook available from National Semiconductor Corporation. Note 5: Current out of a pin is indicated as a negative number. ...
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Typical Performance Characteristics 25° 12V IN VIN Pin Input Current vs. VIN OUT Pin Input Current GATE Pin Source Current Unless otherwise specified the following conditions apply: T SENSE Pin Input Current 30086703 GATE Pin Voltage 30086705 MOSFET ...
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PGD Pin Low Voltage vs. Sink Current UVLO Threshold vs. Temperature OVLO Threshold vs. Temperature www.national.com Input Current, Enabled vs. Temperature 30086708 UVLO Hysteresis Current vs. Temperature 30086757 OVLO Hysteresis Current vs. Temperature 30086766 6 30086758 30086755 30086756 ...
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Current Limit Threshold vs. Temperature Power Limit Threshold vs. Temperature GATE Source Current vs. Temperature Circuit Breaker Threshold vs. Temperature 30086759 GATE Output Voltage vs. Temperature 30086761 PGD Low Voltage vs. Temperature 30086763 7 30086760 30086762 30086765 www.national.com ...
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Block Diagram www.national.com FIGURE 1. Basic Application Circuit 8 30086710 30086711 ...
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Functional Description The LM25069 is designed to control the in-rush current to the load upon insertion of a circuit card into a live backplane or other "hot" power source, thereby limiting the voltage sag on the backplane’s supply voltage, and ...
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Gate Control A charge pump provides the voltage at the GATE pin to en- hance the N-Channel MOSFET’s gate. During normal oper- ating conditions (t3 in Figure 3) the gate held charged by an internal 20 µA ...
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Higher values may result in instability in the current limit control loop. Circuit Breaker If the load current increases rapidly (e.g., the load is short- circuited) the current in the sense resistor (R the current limit threshold before the ...
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Under-Voltage Lock-Out (UVLO) The series pass MOSFET (Q1) is enabled when the input supply voltage ( within the operating range defined by SYS the programmable under-voltage lockout (UVLO) and over- voltage lock-out (OVLO) levels. Typically the UVLO level ...
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Application Information (Refer to Figure 1) CURRENT LIMIT The LM25069 monitors the current in the external MOSFET (Q1) by measuring the voltage across the sense resistor (R ), connected from VIN to SENSE. The required resistor S value ...
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R is the load resistance. The Fault Timeout Period L must be set longer than t to ...
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MOSFET SELECTION It is recommended that the external MOSFET (Q1) selection be based on the following criteria: - The BV rating should be greater than the maximum DSS system voltage (V ), plus ringing and transients which can SYS occur ...
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FIGURE 11. UVLO and OVLO Thresholds Set By R1-R3 The procedure to calculate the resistor values is as follows: - Choose the upper UVLO threshold (V UVLO threshold (V ). UVL - Choose the upper OVLO threshold (V - The ...
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As an example, assume the application requires the following thresholds 8V 7V, V UVH UVL OVH 14V. Therefore V = 1V, and V UV(HYS) OV(HYS) sistor values are kΩ kΩ ...
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FIGURE 15. Adding Delay to the Power Good Output Pin Design-in Procedure The recommended design-in procedure is as follows: • Determine the current limit threshold (I must be higher than the normal maximum load current, allowing for tolerances in the ...
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FIGURE 16. Recommended Board Connector Design 19 30086753 www.national.com ...
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System Considerations A) Continued proper operation of the LM25069 hot swap cir- cuit requires capacitance be present on the supply side of the connector into which the hot swap circuit is plugged in, as depicted in Figure 2. The capacitor ...
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Physical Dimensions inches (millimeters) unless otherwise noted NS Package Number MUB10A 21 www.national.com ...
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