lm5025bmtcx National Semiconductor Corporation, lm5025bmtcx Datasheet
lm5025bmtcx
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lm5025bmtcx Summary of contents
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... Typical Application Circuit Simplified Active Clamp Forward Power Converter © 2006 National Semiconductor Corporation The LM5025B includes a high-voltage start-up regulator that operates over a wide input range of 13V to 100V. Additional features include: Line Under Voltage Lockout (UVLO), soft- start, oscillator UP/DOWN sync capability, precision refer- ence and thermal shutdown ...
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... Connection Diagram Ordering Information Order Number Package Type LM5025BMTC TSSOP-16 LM5025BMTCX TSSOP-16 LM5025BSD LLP-16 LM5025BSDX LLP-16 Pin Descriptions Pin Name 1 V Source Input Voltage IN 2 RAMP Modulator ramp signal 3 CS1 Current sense input for cycle-by-cycle limiting If CS1 exceeds 0.25V the outputs will go into ...
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Pin Descriptions (Continued) Pin Name 7 V Output from the internal high voltage start-up CC regulator. The V 7.6V. 8 OUT_A Main output driver 9 OUT_B Active Clamp output driver 10 PGND Power ground 11 AGND Analog ground 12 SS ...
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Block Diagram www.national.com Simplified Block Diagram 4 20141102 ...
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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 GND GND CC CS1, CS2 to GND All other inputs to GND ESD Rating ...
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Electrical Characteristics Specifications with standard typeface are for T Temperature range 48V Symbol Parameter CS2 Sink Impedance (Post Fault Discharge) CS1 and CS2 Leakage Current Soft-Start Soft-start Current Source Normal Soft-start Current Source following a ...
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Electrical Characteristics Specifications with standard typeface are for T Temperature range 48V Symbol Parameter OUT_B High Saturation OUTPUT_B Peak Current Sink OUT_B Low Saturation OUTPUT_B Rise Time OUTPUT_B Fall Time Output Timing Control Overlap Time ...
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Typical Performance Characteristics V Regulator Start-up Characteristics REF REF Overlap Time vs R www.national.com vs Vin CC 20141103 20141105 SET 20141107 20141104 Oscillator Frequency vs RT 20141106 Overlap Time ...
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Typical Performance Characteristics Dead Time vs R SET SS Pin Current vs Temperature (Continued) Dead Time vs Temperature 20141109 20141111 29.5K SET 20141110 www.national.com ...
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Detailed Operating Description The LM5025B is a functional variant of the LM5025 active clamp PWM controller. The functional differences of the LM5025B are as follows: • The maximum PWM duty cycle is limited to less than 75% to reduce voltage ...
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PWM Outputs (Continued) Compound Gate Drivers The LM5025B contains two unique compound gate drivers, which parallel both MOS and Bipolar devices to provide high drive current throughout the entire switching event. The Bi- polar device provides most of the drive ...
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Maximum Duty Cycle of the PWM clock. The leading edge of OUT_A is delayed with respect to OUT_B by the overlap time which is deter- mined by the TIME pin resistor (K1 x RSET) When operating at maximum duty cycle, ...
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Oscillator and Sync Capability The LM5025B oscillator is set by a single external resistor connected between the RT pin and GND. To set a desired oscillator frequency (F), the necessary RT resistor can be calculated from: 1. (4960/F) ...
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Physical Dimensions inches (millimeters) unless otherwise noted Note recommended that the exposed pad be connected to Pin 11 (AGND) Molded TSSOP-16 NS Package Number MTC16 16-Lead LLP Surface Mount Package NS Package Number SDA16A 15 www.national.com ...
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National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. For the most current product information ...