LT1738EG#TR Linear Technology, LT1738EG#TR Datasheet
LT1738EG#TR
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LT1738EG#TR Summary of contents
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... Protection features include gate drive lockout for low V soft-start, output current limit, short-circuit current limit- ing, gate drive overvoltage clamp and input supply undervoltage lockout. , LTC and LT are registered trademarks of Linear Technology Corporation 12V + ...
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LT1738 ABSOLUTE AXI U RATI GS (Note 1) Supply Voltage (V ) ................................................ 20V IN Gate Drive Current ..................................... Internal Limit V5 Current ................................................. Internal Limit SHDN Pin Voltage .................................................... 20V Feedback Pin Voltage (Trans. 10ms) ...................... ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T other pins open unless otherwise noted. SYMBOL PARAMETER Oscillator and Sync f Max Switch Frequency MAX f Synchronization Frequency Range SYNC V SYNC Pin Input Threshold SYNC R SYNC Pin Input ...
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LT1738 W U TYPICAL PERFOR A CE CHARACTERISTICS Feedback Voltage and Input Current vs Temperature 1.260 1.258 1.256 1.254 1.252 1.250 1.248 1.246 1.244 1.242 1.240 –50 – TEMPERATURE ( C) Feedback Overvoltage Shutdown vs Temperature ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS SHDN Pin Hysteresis Current vs Temperature –50 – 100 125 150 TEMPERATURE ( C) 1738 G09 Slope Compensation 110 V PIN = ...
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LT1738 CTIO S Part Supply V5 (Pin 5): This pin provides a 5V output that can sink or source 10mA for use by external components. V5 source current comes from V . Sink current goes ...
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CTIO S Approximately current can be sourced from this pin if V < V – 0.8V. GCL IN This pin also controls undervoltage lockout of the gate drive. If the pin is ...
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LT1738 CTIO S V (Pin 12): The compensation pin is used for frequency C compensation and current limiting the output of the error amplifier and the input of the current comparator. Loop frequency ...
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U OPERATIO In noise sensitive applications switching regulators tend to be ruled out as a power supply option due to their propensity for generating unwanted noise. When switch- ing supplies are required due to efficiency or input/output constraints, great pains ...
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LT1738 U OPERATIO The current slew feedback loop consists of the voltage across the external sense resistor, which is internally amplified and differentiated. The derivative is limited to a value set The current slew rate is thus ...
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U OPERATIO Table 1. Safety and Protection Features FEATURE Maximum Current Fault Short-Circuit Fault Overvoltage Fault GCL Clamp Gate Drive Undervoltage Lockout Thermal Shutdown V Undervoltage Lockout IN Gate Drive Source and Sink Current Limit V5 Source/Sink Current Limit Shutdown ...
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LT1738 U U APPLICATIO S I FOR ATIO Oscillator frequency is important for noise reduction in two ways. First the lower the oscillator frequency the lower the waveform’s harmonics, making it easier to filter them. Second the oscillator will control ...
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U U APPLICATIO S I FOR ATIO Table 2 INPUT VOLTAGE CAPACITOR VALUE < 25V 50V 2.5pF 100V Smaller value capacitors can be made in two ways. The first is simply combining two capacitors in series. The equivalent capacitance is ...
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LT1738 U U APPLICATIO S I FOR ATIO most of the control circuitry of the regulator. Note after the control circuitry powers on, gate driver activity will depend on the voltage of V with respect to the voltage on GCL. ...
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U U APPLICATIO S I FOR ATIO Setting Current Limit The sense resistor sets the value for maximum operating current. When the CS pin voltage is 0.1V the gate driver will immediately go low (no slew control). Therefore the sense ...
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... Select an inductor that can handle peak current, average current (heating effects) and fault current. 5. Finally, double check output voltage ripple. The experts in the Linear Technology Applications depart- ment have experience with a wide range of inductor types and can assist you in making a good choice. ...
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U U APPLICATIO S I FOR ATIO The worst component from an AC point is the gate charge current. The actual peak current depends on gate capaci- tance and slew rate, being higher for larger values of each. The total ...
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LT1738 U U APPLICATIO S I FOR ATIO First determine the maximum gate drive that you require. Typically you will want least 2V greater than the rated threshold. Higher voltages will lower the on resis- tance ...
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... FLASH SHALL NOT EXCEED .254mm (.010") 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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... Low Noise Step-Down Switching Regulator LTC1922-1 Synchronous Phase Modulated Full-Bridge Controller LT3439 Ultralow Noise Transformer Driver DirectSense is a trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 Ultralow Noise 30W Offline Power Supply ...