LTC3803-5 Linear Technology, LTC3803-5 Datasheet
LTC3803-5
Related parts for LTC3803-5
LTC3803-5 Summary of contents
Page 1
... V can be powered from a high V its internal 8V shunt regulator. An internal undervoltage lockout shuts down the IC when the input voltage falls below 3.2V, guaranteeing at least 3.2V of gate drive to the external MOSFET. The LTC3803-5 is available in a low profile (1mm) 6-lead SOT-23 (ThinSOT U 10MQ100N VPH5-0155 13V/0.3A 20mA MIN 1µ ...
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... LTC3803E-5 ....................................... – 40°C to 85°C LTC3803H-5 (Note 3) ....................... – 40°C to 150°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C *LTC3803-5 internal clamp circuit self regulates V ELECTRICAL CHARACTERISTICS to 85°C operating junction temperature range, otherwise specifications are at T SYMBOL ...
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... Note 4: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. Note 5: The LTC3803-5 is tested in a feedback loop that servos V output of the error amplifier while maintaining I the current limit range. Note 6: Peak current sense voltage is reduced dependent on duty cycle ...
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... LTC3803-5 W TYPICAL PERFOR A CE CHARACTERISTICS Reference Voltage vs Temperature www.datasheet4u.com 812 808 804 800 796 792 788 –50 –30 – 110 130 TEMPERATURE (°C) Oscillator Frequency vs Temperature 220 215 210 205 200 195 190 185 180 50 70 –50 – ...
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... TEMPERATURE (°C) 38035 G10 110 130 150 38035 G13 LTC3803-5 I /RUN Start-Up Current Source TH vs Temperature 1000 0.1V CC TURNON 900 ITH/RUN 800 700 600 500 400 300 ...
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... Nominal voltage range is www.datasheet4u.com 0.7V to 1.9V. Forcing this pin below 0.28V causes the LTC3803-5 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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... U OPERATIO The LTC3803 constant frequency current mode controller for flyback, SEPIC and DC/DC boost converter applications in a tiny ThinSOT package. The LTC3803-5 is www.datasheet4u.com 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 LTC3803-5’ ...
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... V voltage to around 8V as long as the V to sink more than 25mA. This shunt regulator is always (nominally active, even when the LTC3803 shutdown, since it SHDN serves the vital function of protecting the V seeing too much voltage. ...
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... U U APPLICATIO S I FOR ATIO Many LTC3803-5 application circuits can be derived from the topology shown in Figure 2. www.datasheet4u.com The LTC3803-5 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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... Figure 2). This current ramp starts at zero right SL after the NGATE pin has been high for the LTC3803-5’s minimum duty cycle of 6.5%. The current rises linearly towards a peak of 5µA at the maximum duty cycle of 80%, shutting off once the NGATE pin goes low. A series resistor ...
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... S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 0.95 REF 1.22 REF 1.50 – 1.75 2.80 BSC 1.4 MIN (NOTE 4) 1.00 MAX 0.30 – 0.50 REF 0.09 – 0.20 (NOTE 3) LTC3803-5 BAS516 • SECONDARY SIDE 2.2µF 10V, 100mA OUTPUT SECONDARY SIDE GROUND T1: PULSE ENGINEERING PA0648 OR TYCO TTI8698 38035 TA03 2.90 BSC (NOTE 4) PIN ONE ID 0.95 BSC 0.80 – ...
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... LTC3803-5 TYPICAL APPLICATIO S 90% Efficient Synchronous Flyback Converter V IN www.datasheet4u.com 36V TO 72V C 270k 1n 33k /RUN GATE TH LTC3803-5 560 GND CC 8.06k SENSE FB 25.5k* 1µ 10V V OUT T1: PULSE ENGINEERING PA1006 D1: PHILIPS BAS516 Q1: FAIRCHILD FDC2512 C : TDK 1µF, 100V, X5R ...