LTC3803 LINER [Linear Technology], LTC3803 Datasheet
LTC3803
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LTC3803 Summary of contents
Page 1
... LTC3803-based con- verters to accept input supplies beyond the LTC3803’s absolute maximum V feature allows efficient operation at high input voltages. For simplicity, the LTC3803 can also be powered from a high V IN regulator. An internal undervoltage lockout shuts down the LTC3803 when the input voltage falls below 4.6V, guaranteeing at least 4 ...
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... Peak Slope Compensation Output Current SLMAX t Soft-Start Time SFST Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LTC3803E is guaranteed to meet specifications from Specifications over the – operating temperature range 2 U RATINGS PACKAGE/ORDER * ...
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... C/W Note 4: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. Note 5: The LTC3803 is tested in a feedback loop that servos V output of the error amplifier while maintaing I TH the current limit range TYPICAL PERFOR A CE CHARACTERISTICS Reference Voltage vs Temperature 800 ...
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... LTC3803 W U TYPICAL PERFOR A CE CHARACTERISTICS V Undervoltage Lockout CC Thresholds vs Temperature 10.0 9.5 9.0 V TURNON 8.5 8.0 7.5 7.0 6.5 V 6.0 TURNOFF 5.5 5.0 –50 –30 – 110 TEMPERATURE ( C) 3803 G07 Start-Up I Supply Current CC vs Temperature – 0.1V CC TURNON –50 –30 – 110 TEMPERATURE ( C) 3803 G10 ...
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... TH serves as the error amplifier compensation point as well as the run/shutdown control input. Nominal voltage range is 0.7V to 1.9V. Forcing this pin below 0.28V causes the LTC3803 to shut down. In shutdown mode, the NGATE pin is held low. GND (Pin 2): Ground Pin. V (Pin 3): Receives the feedback voltage from an exter- FB nal resistive divider across the output ...
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... OPERATIO The LTC3803 is a constant frequency current mode con- troller for flyback and DC/DC boost converter applications in a tiny ThinSOT package. The LTC3803 is designed so that none of its pins need to come in contact with the input or output voltages of the power supply circuit of which part, allowing the conversion of voltages well beyond the LTC3803’ ...
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... LTC3803-based power supplies to rise in a smooth and controlled manner on start-up. Powering the LTC3803 In the simplest case, the LTC3803 can be powered from a TURNON high voltage supply through a resistor. A built-in shunt regulator from the V current as needed through this resistor to regulate the V voltage to around 9 ...
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... LTC3803 U U APPLICATIO S I FOR ATIO Many LTC3803 application circuits can be derived from the topology shown in Figure 2. The LTC3803 itself imposes no limits on allowed power output, input voltage V or desired regulated output IN voltage V ; these are all determined by the ratings on the OUT external power components. The key factors are: Q1’s ...
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... NGATE pin begins switching and the external MOSFET (Q1) begins to deliver power. The voltage decline as the LTC3803 draws its normal supply cur- rent, which exceeds that delivered by R time, typically tens of milliseconds, the output voltage approaches its desired value. By this time, the third ...
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... IN R LTC3803 VCC GND VCC Figure 3. Powering the LTC3803 Via the Internal Shunt Regulator from overvoltage transients as the third winding is pow- ering up. In applications where a third transformer winding is unde- sirable or unavailable, the shunt regulator allows the turn-on thresh- LTC3803 to be powered through a single dropping resistor ...
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... MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193 U S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 1.22 REF 1.50 – 1.75 2.80 BSC 1.4 MIN (NOTE 4) 0.95 BSC 0.80 – 0.90 1.00 MAX 0.09 – 0.20 (NOTE 3) LTC3803 2.90 BSC (NOTE 4) PIN ONE ID 0.30 – 0.45 6 PLCS (NOTE 3) 0.01 – 0.10 1.90 BSC S6 TSOT-23 0302 11 3803i ...
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... Burst Mode is a registered trademark of Linear Technology Corporation Linear Technology Corporation 12 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 2W Housekeeping Telecom Converter BAS516 T1 • 2 BAS516 • BAS516 9.2k 1k 220k • LTC3803 /RUN NGATE FDC2512 GND CC 5. SENSE ...