LTC3704EMS Linear Technology, LTC3704EMS Datasheet
LTC3704EMS
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LTC3704EMS Summary of contents
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... SENSE pin to a resistor in the source of the power MOSFET. The LTC3704 is available in the 10-lead MSOP package. , LTC, LT and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners ...
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... PACKAGE/ORDER I FOR ATIO + 0.3V INTVCC ORDER PART NUMBER LTC3704EMS LTC3704IMS Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specified with wider operating temperature ranges. ...
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ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are 5V 1.5V 80k INTVCC RUN FREQ SYMBOL PARAMETER Oscillator f Oscillator ...
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LTC3704 W U TYPICAL PERFOR A CE CHARACTERISTICS NFB Voltage vs Temp –1.25 –1.24 –1.23 –1.22 –1. –50 – 100 125 TEMPERATURE (°C) 3704 G01 Shutdown Mode ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS RUN Thresholds 1.5 1.4 1.3 1 (V) IN 3704 G10 Frequency vs Temperature 325 320 315 310 305 300 295 290 285 280 275 ...
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LTC3704 CTIO S RUN (Pin 1): The RUN pin provides the user with an accurate means for sensing the input voltage and pro- gramming the start-up threshold for the converter. The falling RUN pin threshold ...
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W BLOCK DIAGRA FREQ 4 0.62V MODE/SYNC 5 NFB 200k – 3 BUFFER + – + 1.230V INTV CC 5.2V 8 – + 2.00V SLOPE COMPENSATION V-TO-I OSC I OSC 50k 200k + 0.30V EA – g ...
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LTC3704 U OPERATIO Main Control Loop The LTC3704 is a constant frequency, current mode controller for DC/DC positive-to-negative converter appli- cations. The LTC3704 is distinguished from conventional current mode controllers because the current control loop can be closed by sensing ...
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U OPERATIO minimum on-time (about 175ns). Below this output current level, the converter will begin to skip cycles in order to maintain output regulation. Figures 3 and 4 show the light load switching waveforms for Burst Mode and Pulse-Skip Mode ...
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LTC3704 U U APPLICATIO S I FOR ATIO MODE/ SYNC t = 25ns MIN 0.8T GATE Figure 5. MODE/SYNC Clock Input and Switching Waveforms for Synchronized Operation Programming the Operating Frequency The choice of operating ...
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U U APPLICATIO S I FOR ATIO cause the LTC3704 to exceed its maximum junction temperature rating. The junction temperature can be estimated using the following equations: ≈ • Q Q(TOT ...
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LTC3704 U U APPLICATIO S I FOR ATIO The resistor R1 is typically chosen to be less than 1M. For applications where the RUN pin is only to be used as a logic input, the user should be aware of ...
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U U APPLICATIO S I FOR ATIO Applications Circuits A simple positive-to-negative application circuit for the LTC3704 is shown in Figure 1. The basic operation of this circuit is shown in Figure 9. During the on-time the inductor currents flow ...
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LTC3704 U U APPLICATIO S I FOR ATIO internal ramp compensation (at duty cycles above 50%), and the converter operation will approach voltage mode (ramp compensation reduces the gain of the current loop). If too small an inductor is used, ...
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U U APPLICATIO S I FOR ATIO the initial equations for I and I L1(PEAK) inductor is used, make sure that the minimum saturation current for the parallel configuration exceeds the maxi- mum switch current, or: ⎛ ⎞ χ ≥ ...
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LTC3704 U U APPLICATIO S I FOR ATIO 200 150 100 0.2 0.4 0.5 DUTY CYCLE Figure 11. Maximum SENSE Threshold Voltage vs Duty Cycle Another method of choosing which power MOSFET to use is to check ...
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U U APPLICATIO S I FOR ATIO The used in this equation normally includes TH(JA) the R for the device plus the thermal resistance from TH(JC) the case to the ambient temperature ( can then ...
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LTC3704 U U APPLICATIO S I FOR ATIO 1 ( – ≥ MAX I • RMS COUT ( ) should be noted that these equations assume no cou- pling between the inductors. If the ...
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U U APPLICATIO S I FOR ATIO Aluminum electrolytic and dry tantalum capacitors are both available in surface mount packages. In the case of tantalum critical that the capacitors have been surge tested for use in switching power ...
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LTC3704 U U APPLICATIO S I FOR ATIO regulator feedback loop acts on the resulting error amp output signal to return V to its steady-state value. During O this recovery time, V can be monitored for overshoot or O ringing ...
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U U APPLICATIO S I FOR ATIO • O(MAX) F Assuming a maximum junction temperature of 125°C and a forward voltage of approximately 0.33V at 3A (the maximum output current 15V), this ...
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LTC3704 U U APPLICATIO S I FOR ATIO V (AC) OUT 10mV/DIV I (DC) L2 1A/DIV 1μs/DIV –2V OUT Figure 18. Output Ripple Voltage and Inductor Current for the Circuit in Figure 15 V ...
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U U APPLICATIO S I FOR ATIO PC Board Layout Checklist 1. In order to minimize switching noise and improve output load regulation, the GND pin of the LTC3704 should be connected directly to 1) the negative termi- nal of ...
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LTC3704 U U APPLICATIO S I FOR ATIO 2. Beware of ground loops in multiple layer PC boards. Try to maintain one central ground node on the board and use the input capacitor to avoid excess input ripple for high ...
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U U APPLICATIO S I FOR ATIO R C 14. 4.7nF R T 80. 2.49k 1% D1: DIODES INC B320B L1, L2: BH ELECTRONICS BH 510-1009 M1: SILICONIX Si9426 3.0 3.5 4.0 ...
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LTC3704 U U APPLICATIO S I FOR ATIO 5.4V UV – 49.9k 150k 1nF C C2 100pF RUN I TH LTC3704 R C NFB 82k FREQ C C1 MODE/SYNC ...
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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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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... LT1931 Inverting 1.2MHz, SOT-23 Converter TM LT1964 ThinSOT Linear Low Dropout Regulator LTC3401/LTC3402 1A/2A 3MHz Synchronous Boost Converters ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● High Efficiency Positive-to-Negative Converter ...