LTC3703IG-5#PBF Linear Technology, LTC3703IG-5#PBF Datasheet
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LTC3703IG-5#PBF
Specifications of LTC3703IG-5#PBF
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LTC3703IG-5#PBF Summary of contents
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... Telecom and Base Station Power Supplies ■ Networking Equipment, Servers ■ Automotive and Industrial Control , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. *U.S. Patent Numbers: 5408150, 5055767, 6677210, 5847554, 5481178, 6304066, 6580258; Others Pending. U ...
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... V = DRV = BOOST = 25k, unless otherwise specified. CONDITIONS RUN/ (Note 5) RUN/ (Note 5) RUN/ COMP Voltages ................... –0. ORDER PART TOP VIEW NUMBER 28 BOOST 27 TG LTC3703EG LTC3703IG DRV BGRTN G PACKAGE = 125°C, θ = 100°C ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T BGRTN = 0V, RUN/ open, R MAX SET SYMBOL PARAMETER Main Control Loop V Feedback Voltage FB ∆V Feedback Voltage Line Regulation FB, LINE ∆V Feedback Voltage Load ...
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LTC3703 TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Input Voltage 100 OUT OUT OUT f = 250kHz FORCED CONTINUOUS ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Driver Peak Source Current vs Temperature 1 1.1 1.0 0.9 0.8 –60 –40 – 100 120 140 TEMPERATURE (°C) 37035 G10 Driver Pull-Down R ...
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LTC3703 TYPICAL PERFOR A CE CHARACTERISTICS I Current vs Temperature MAX –60 –40 – 100 120 140 TEMPERATURE (°C) 37035 G19 Shutdown Threshold vs Temperature 1.4 1.2 1.0 0.8 0.6 ...
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CTIO S (GN16/G28) MODE/SYNC (Pin 1/Pin 6): Pulse Skip Mode Enable/Sync Pin. This multifunction pin provides Pulse Skip Mode en- able/disable control and an external clock input for synchro- nization of the internal oscillator. Pulling ...
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LTC3703 CTIO AL DIAGRA 4µA RUN/SS – 3.2V UVSD OTSD SYNC MODE/SYNC 1 DETECT COMP 3 + ÷ 0. – (<15V) ...
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U OPERATIO (Refer to Functional Diagram) When the load current increases, it causes a drop in the feedback voltage relative to the reference. The COMP volt- age then rises, increasing the duty ratio until the output feedback voltage again matches ...
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LTC3703-5 U OPERATIO (Refer to Functional Diagram) MOSFETs can occur. To prevent this from occuring, the bottom driver return is brought out as a separate pin (BGRTN) so that a negative supply can be used to reduce the effect of ...
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U OPERATIO (Refer to Functional Diagram) For maximum protection, the LTC3703-5 current limit consists of a steady-state limit circuit and an instanta- neous limit circuit. The steady-state limit circuit amplifier that pulls a current from the RUN/SS ...
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LTC3703-5 U OPERATIO (Refer to Functional Diagram) Buck or Boost Mode Operation The LTC3703-5 has the capability of operating both as a step-down (buck) and step-up (boost) controller. In boost mode, output voltages as high as 60V can be tightly ...
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U U APPLICATIO S I FOR ATIO The oscillator can also be synchronized to an external clock applied to the MODE/SYNC pin with a frequency in the range of 100kHz to 600kHz (refer to the MODE/SYNC Pin section for more ...
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LTC3703 APPLICATIO S I FOR ATIO appropriate breakdown specification. Since most MOSFETs in the 30V to 60V range have logic level thresholds ≥ 4.5V), the LTC3703-5 is designed to be used (V GS(MIN) with a 4.5V to 15V ...
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U U APPLICATIO S I FOR ATIO Multiple MOSFETs can be used in parallel to lower R and meet the current and thermal requirements if desired. The LTC3703-5 contains large low impedance drivers capable of driving large gate capacitances without ...
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... MOSFET(s). The reverse breakdown of the external diode, D greater than V for the external diode is the reverse recovery and reverse leakage, either of which may cause excessive reverse ThinSOT is a tradmark of Linear Technology Corporation. and BOOST) CC package and a chip inductor for minimal extra 2 ) ...
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U U APPLICATIO S I FOR ATIO 1µ LTC3703 DRV BG CC BGRTN Figure 9a. V Generated from 5V < ...
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LTC3703 APPLICATIO S I FOR ATIO node dV/dt can be many volts/ns, which will pull up on the gate of the bottom MOSFET through its Miller capacitance. If this Miller current, times the internal gate resistance of the ...
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U U APPLICATIO S I FOR ATIO GAIN A V –12dB/OCT 0 PHASE –6dB/OCT Figure 10. Transfer Function of Buck Modulator feedback amplifier, on the other hand, gives us a handle with which to adjust the AC response. The goal ...
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... AC plot of V degrees. Refer to your SPICE manual for details of OUT how to generate this plot. *3703-5 modulator gain/phase *2003 Linear Technology *this file written to run with PSpice 8.0 *may require modifications for other SPICE simulators *MOSFETs rfet mod sw 0.02 *inductor lext sw out1 10u rl out1 out 0 ...
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U U APPLICATIO S I FOR ATIO BOOST values greater than 60° usually require Type 3 loops for satisfactory performance. Finally, choose a convenient resistor value for R1 (10k is usually a good value). Now calculate the remaining values: (K ...
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LTC3703 APPLICATIO S I FOR ATIO Boost Converter: Power MOSFET Selection For information about choosing power MOSFETs for a boost converter, see the Power MOSFET Selection sec- tion for the buck converter, since MOSFET selection is similar. However, ...
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U U APPLICATIO S I FOR ATIO maximum junction temperature. The maximum inductor current is a function of both duty cycle and maximum load current, so the limit must be set for the maximum expected duty cycle (minimum V ) ...
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LTC3703 APPLICATIO S I FOR ATIO the RUN/SS pin allows an internal 4µA current source to charge up the soft-start capacitor C on RUN/SS reaches 1V, the LTC3703-5 begins operating at its minimum on-time. As the RUN/SS voltage ...
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U U APPLICATIO S I FOR ATIO MODE/SYNC Pin (External Synchronization) The internal LTC3703-5 oscillator can be synchronized to an external oscillator by applying and clocking the MODE/ SYNC pin with a signal above 2V . The internal oscillator P-P ...
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LTC3703 APPLICATIO S I FOR ATIO MOSFET and the synchronous MOSFET. If the two MOSFETs have approximately the same R resistance of one MOSFET can simply be summed with the 2 DCR resistance obtain I ...
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U U APPLICATIO S I FOR ATIO Measurement Techniques Measuring transient response presents a challenge in two respects: obtaining an accurate measurement and gener- ating a suitable transient to test the circuit. Output mea- surements should be taken with a ...
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LTC3703 APPLICATIO S I FOR ATIO estimated at maximum input voltage, assuming a junction temperature of 100°C (30°C above an ambient of 70°C 007 100 25 0 ...
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U U APPLICATIO S I FOR ATIO 5. Place the small-signal components away from high frequency switching nodes (BOOST, SW, TG, and BG). In the layout shown in Figure 20, all the small signal compo- nents have been placed on ...
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LTC3703-5 U TYPICAL APPLICATIO S 15V-60V Input Voltage to 12V/10A Step-Down Converter with Pulse Skip Mode Enabled R C1 10k 470pF 1000pF R MAX R2 C 8.06k 0.1µ 100Ω 113k C C3 ...
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... DIMENSIONS ARE IN (INCHES) 3. DRAWING NOT TO SCALE 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 Package 16-Lead Plastic SSOP (Narrow ...
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... Supply Current, 16-Pin SSOP ≤ 60V, No Protection Diode Required, 8-Lead MSOP OUT ≤ 60V, 0.1Ω Saturation Switch, 16-Pin SSOP ≤ 36V OUT LT/LT 0505 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2004 ≤ 20A OUT 37035fa ...