LTC3703EGN Linear Technology, LTC3703EGN Datasheet

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... Telecom and Base Station Power Supplies n Networking Equipment, Servers n Automotive and Industrial Control L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5408150, 5055767, 6677210, 5847554, 5481178, 6304066, 6580258. TYPICAL APPLICATION ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T BGRTN = 0V, RUN/ open, R MAX SET SYMBOL PARAMETER V , DRV V , DRV Supply Voltage Pin Voltage IN ...

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LTC3703 ELECTRICAL CHARACTERISTICS Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3703E ...

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TYPICAL PERFORMANCE CHARACTERISTICS V Shutdown Current vs CC Temperature –50 – 100 125 TEMPERATURE (°C) 3703 G07 Driver Peak Source Current vs Temperature 3 10V ...

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LTC3703 TYPICAL PERFORMANCE CHARACTERISTICS RUN/SS Pull-Up Current vs V Voltage VOLTAGE (V) CC 3703 G16 I Current vs Temperature MAX –50 –25 0 ...

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PIN FUNCTIONS (GN16/G28) MODE/SYNC (Pin 1/Pin 6): Pulse-Skip Mode Enable/Sync Pin. This multifunction pin provides pulse-skip mode enable/disable control and an external clock input for synchronization of the internal oscillator. Pulling this pin below 0. external logic-level ...

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LTC3703 FUNCTIONAL DIAGRAM GN16 4μA RUN/SS – 0.9V 3.2V UVSD OTSD MODE/SYNC SYNC 1 DETECT COMP 3 + 0.8V ÷ – (<15V) 12 OVER TEMP ...

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OPERATION (Refer to Functional Diagram) drop in the feedback voltage relative to the reference. The COMP voltage then rises, increasing the duty ratio until the output feedback voltage again matches the reference voltage. In normal operation, the top MOSFET is ...

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LTC3703 OPERATION (Refer to Functional Diagram) side 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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OPERATION (Refer to Functional Diagram) For maximum protection, the LTC3703 current limit con- sists of a steady-state limit circuit and an instantaneous limit circuit. The steady-state limit circuit that pulls a current from the RUN/SS pin proportional ...

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LTC3703 OPERATION (Refer to Functional Diagram) Buck or Boost Mode Operation The LTC3703 has the capability of operating both as a step-down (buck) and step-up (boost) controller. In boost mode, output voltages as high as 80V can be tightly regu- ...

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APPLICATIONS INFORMATION 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 details). In this synchronized mode, ...

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LTC3703 APPLICATIONS INFORMATION breakdown specifi cation. Since many high voltage MOSFETs have higher threshold voltages (typically, V the LTC3703 is designed to be used with 15V gate drive supply (DRV pin). CC For maximum effi ciency, on-resistance ...

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APPLICATIONS INFORMATION The term (1 + δ) is generally given for a MOSFET in the form of a normalized R vs temperature curve, and DS(ON) typically varies from 0.005/°C to 0.01/°C depending on the particular MOSFET used. Multiple MOSFETs can ...

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... SW is low. When the B CC topside MOSFET is turned on, the driver places the C voltage across the gate source of the top MOSFET. The switch node voltage, SW, rises to V follows. With the topside MOSFET on, the boost voltage ThinSOT is a trademark of Linear Technology Corporation. and connected to the B B ...

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APPLICATIONS INFORMATION 1μ LTC3703 DRV BG CC BGRTN Figure 10a. V Generated from 10V < OPTIONAL V CC CONNECTION 10V ...

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LTC3703 APPLICATIONS INFORMATION Bottom MOSFET Source Supply (BGRTN) The bottom gate driver, BG, switches from DRV BGRTN where BGRTN can be a voltage between ground and –5V. Why not just keep it simple and always connect BGRTN to ground? In ...

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APPLICATIONS INFORMATION will approach its ESR and the rolloff due to the capaci- tor will stop, leaving 6dB/octave and 90° of phase shift (Figure 11). GAIN A V –12dB/OCT 0 PHASE –6dB/OCT Figure 11. Transfer Function of Buck Modulator So ...

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... SPICE deck and generate an AC plot of V(V OUT degrees. Refer to your SPICE manual for details of how to generate this plot. *3703 modulator gain/phase *2003 Linear Technology *this fi le written to run with PSpice 8.0 *may require modifi cations for other SPICE simulators *MOSFETs rfet mod sw 0.02 ...

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APPLICATIONS INFORMATION Finally, choose a convenient resistor value for R1 (10k is usually a good value). Now calculate the remaining values constant used in the calculations chosen crossover frequency (GAIN/20 (this converts ...

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LTC3703 APPLICATIONS INFORMATION similar. However, note that the power dissipation equations for the MOSFETs at maximum output current in a boost converter are: 2 ⎛ ⎞ MAX = + ⎝ ⎜ ⎠ ⎟ MAIN MAX ...

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APPLICATIONS INFORMATION cycle (minimum order to ensure that the current IN limit does not kick in at loads < I O(MAX MAX ( ) = 1 δ PROG DS ON ...

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LTC3703 APPLICATIONS INFORMATION charge up the soft-start capacitor C on RUN/SS reaches 0.9V, the LTC3703 begins operating at its minimum on-time. As the RUN/SS voltage increases from 1.4V to 3V, the duty cycle is allowed to increase from 0% to ...

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APPLICATIONS INFORMATION MODE/SYNC Pin (External Synchronization) The internal LTC3703 oscillator can be synchronized to an external oscillator by applying and clocking the MODE/SYNC pin with a signal above 2V oscillator locks to the external clock after the second clock transition ...

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LTC3703 APPLICATIONS INFORMATION 1. V supply current. The V current is the DC supply CC CC current given in the Electrical Characteristics table which powers the internal control circuitry of the LTC3703. Total supply current is typically about 2.5mA and ...

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APPLICATIONS INFORMATION With most output capacitors, several devices paralleled to get the ESR down will have so much capacitance that this drop term is negligible. Ceramic capacitors are an exception; a small ceramic capacitor can have suitably low ESR with ...

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LTC3703 APPLICATIONS INFORMATION Next, choose the top and bottom MOSFET switch. Since the drain of each MOSFET will see the full supply voltage 72V (max) plus any ringing, choose a 100V MOSFET to provide a margin of safety. Si7456DP has ...

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APPLICATIONS INFORMATION 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 components have been placed on one side of the IC and all ...

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LTC3703 TYPICAL APPLICATIONS 36V-72V Input Voltage to 5V/10A Step-Down Converter with Pulse Skip Mode Enabled R C1 10k 1000pF 470pF R MAX R2 21.5k 1% 0.1μ 113k 100Ω 2200pF Single ...

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... 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. GN Package 16-Lead Plastic SSOP (Narrow .150 Inch) (Reference LTC DWG # 05-08-1641) ...

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... Monolithic 3A, 200kHz/500kHz Step-Down Regulator LT3433 Monolithic Step-Up/Step-Down DC/DC Converter LTC3703-5 60V Synchronous DC/DC Controller LT3800 60V Synchronous DC/DC Controller trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 12V to 24V/5A Synchronous Boost Converter ...