LTC3803-3 LINER [Linear Technology], LTC3803-3 Datasheet
LTC3803-3
Related parts for LTC3803-3
LTC3803-3 Summary of contents
Page 1
... IN regulator. An internal undervoltage lockout shuts down the LTC3803-3 when the input voltage falls below 4.4V, guaranteeing at least 4.4V of gate drive to the external MOSFET. The LTC3803-3 is available in a low profile (1mm) 6-lead SOT-23 (ThinSOT UPS840 V OUT 5V 2A MAX 300μ ...
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... LTC3803E-3 ....................................... – 40°C to 85°C LTC3803I-3 ...................................... – 40°C to 125°C Junction Temperature (Note 3) ............................ 125°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C *LTC3803-3 internal clamp circuit self regulates V voltage to 9.5V. CC ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T ...
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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 LTC3803-3 is tested in a feedback loop that servos V output of the error amplifier while maintaing I the current limit range. Note 6: Peak current sense voltage is reduced dependent on duty cycle ...
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... LTC3803 TYPICAL PERFOR A CE CHARACTERISTICS Reference Voltage vs Temperature 812 808 804 800 796 792 788 –30 – 110 – TEMPERATURE (°C) 38033 G01 Oscillator Frequency vs Temperature 330 320 310 300 290 280 270 –50 –30 –10 ...
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... TEMPERATURE (°C) Soft-Start Time vs Temperature 3.5 3.0 2.5 2.0 1.5 1.0 0 110 130 –50 38033 G13 LTC3803 25°C unless otherwise noted /RUN Start-Up Current Source TH vs Temperature 700 0.1V CC TURNON ITH/RUN 600 500 400 300 200 100 0 – ...
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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 LTC3803-3 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 constant frequency current mode controller for flyback and DC/DC boost converter applica- tions in a tiny ThinSOT package. The LTC3803-3 is de- signed 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 LTC3803-3’ ...
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... TURNOFF ITH/RUN (NOMINALLY 5.7V) (NOMINALLY 0.28V) LTC3803-3 ENABLED 38033 F01 Figure 1. Start-Up/Shutdown State Diagram The undervoltage lockout (UVLO) mechanism prevents the LTC3803-3 from trying to drive a MOSFET with insuf- ficient V . The voltage at the (nominally 8.7V) at least momentarily to enable TURNON 8 LTC3803-3 operation. The V fall to V lockout disables the LTC3803-3 ...
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... MOSFET gate driver. CC pin is not forced CC Adjustable Slope Compensation The LTC3803-3 injects a 5μA peak current ramp out through its SENSE pin which can be used for slope compensation pin from CC in designs that require it. This current ramp is approximately linear and begins at zero current at 8% duty cycle, reach- ...
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... LTC3803 APPLICATIO S I FOR ATIO Many LTC3803-3 application circuits can be derived from the topology shown in Figure 2. The LTC3803-3 itself imposes no limits on allowed power output, input voltage V or desired regulated output volt- IN age V ; these are all determined by the ratings on the OUT external power components. The key factors are: Q1’ ...
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... Figure 2). This current ramp starts at zero right SL after the NGATE pin has been high for the LTC3803-3’s minimum duty cycle of 8%. 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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... It should be made large enough to yield a worst- case maximum charging current less than the minimum rated LTC3803-3 supply current, so that in operation, most of the LTC3803-3’s supply current is delivered through the third winding. This results in the highest possible efficiency. Capacitor C should then be made large enough to avoid VCC the relaxation oscillation behavior described above ...
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... BAS516 • BAS516 9.2k 1k 220k • LTC3803 /RUN NGATE FDC2512 GND CC 5. SENSE FB 1μF 0.1Ω PRIMARY GROUND 38033 TA03 LTC3803-3 SECONDARY SIDE 2.2μF 10V, 100mA OUTPUT SECONDARY SIDE GROUND T1: PULSE ENGINEERING PA0648 OR TYCO TTI8698 38033fa 13 ...
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... LTC3803-3 U TYPICAL APPLICATIO S 4:1 Input Range 3.3V Output Isolated Flyback DC/DC Converter + 72V 2.2μF 220k – MMBTA42 V IN PDZ6. /RUN GATE TH LTC3803 GND SENSE PA1277NL • 100k • 68Ω 150pF BAS516 22Ω 680Ω • 0.1μF FDC2512 4 ...
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... 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) LTC3803-3 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 38033fa 15 ...
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... LTC3803-3 U TYPICAL APPLICATIO S 90% Efficient Synchronous Flyback Converter V IN 36V TO 72V 220k 1n 33k /RUN GATE TH LTC3803-3 560Ω GND CC 8.06k 0.8V SENSE FB 25.5k* 10μF R 10V FB V OUT T1: PULSE ENGINEERING PA1006 C : TDK 1μF, 100V, X5R IN Q1: FAIRCHILD FDC2512 C : TDK 100μF, 6.3V, X5R ...