LTC3703IGN-5 Linear Technology, LTC3703IGN-5 Datasheet
LTC3703IGN-5
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LTC3703IGN-5 Summary of contents
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... Telecom and Base Station Power Supplies ■ Networking Equipment, Servers ■ Automotive and Industrial Control , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Protected by U.S. Patents including 5408150, 5055767, 6677210, 5847554, 5481178, 6304066, 6580258. U TYPICAL APPLICATIO MODE/SYNC 30k ...
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... Junction Temperature (Notes 3, 7) LTC3703E, LTC3703I ....................................... 125°C LTC3703H (Note 9) .......................................... 150°C Storage Temperature Range ................. –65°C to 150°C Lead Temperature (Soldering, 10 sec.)................. 300° ORDER PART NUMBER LTC3703EGN LTC3703IGN MODE/SYNC 6 LTC3703HGN f 7 SET COMP PART I 10 MAX INV 11 MARKING NC 12 RUN/SS ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T BGRTN = 0V, RUN/ open, R MAX SET SYMBOL PARAMETER ∆V Feedback Voltage Line Regulation FB, LINE ∆V Feedback Voltage Load Regulation FB, LOAD V MODE/SYNC Threshold MODE/SYNC ...
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LTC3703 W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Input Voltage 100 OUT 0.5A OUT 12V 75 OUT f = 300kHz PULSE SKIP DISABLED ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Driver Peak Source Current vs Temperature 3 10V CC 2.8 2.6 2.4 2.2 2.0 1.8 1.6 1.4 1.2 1.0 –50 – 125 150 100 TEMPERATURE (°C) 3703 ...
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LTC3703 W U TYPICAL PERFOR A CE CHARACTERISTICS I Current vs Temperature MAX –50 – 100 125 150 TEMPERATURE (°C) 3703 G19 Shutdown Threshold vs Temperature 1.4 1.2 1.0 0.8 0.6 0.4 0.2 ...
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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 enable/disable control and an external clock input for synchronization of the internal oscillator. Pulling this pin ...
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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) output feedback voltage again matches the reference voltage. In normal operation, the top MOSFET is turned on when the RS latch is set by the on-chip oscillator and is turned off when the PWM ...
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LTC3703 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 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 to the difference ...
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LTC3703 U OPERATIO 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 regulated. With the INV ...
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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 U U APPLICATIO S I FOR ATIO appropriate breakdown specification. Since many high voltage MOSFETs have higher threshold voltages (typi- ≥ 6V), the LTC3703 is designed to be used cally, V GS(MIN) with 15V gate drive ...
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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 contains large low impedance drivers ca- pable of driving large gate capacitances ...
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LTC3703 U U APPLICATIO S I FOR ATIO Since ∆I increases with input voltage, the output ripple is L highest at maximum input voltage. ESR also has a signifi- cant effect on the load transient response. Fast load transitions at ...
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U U APPLICATIO S I FOR ATIO 1µ LTC3703 DRV BG CC BGRTN Figure 10a. V Generated from 10V < ...
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LTC3703 U U APPLICATIO S I FOR ATIO Bottom MOSFET Source Supply (BGRTN) The bottom gate driver, BG, switches from DRV where BGRTN can be a voltage between ground and –5V. Why not just keep it simple and always connect ...
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U U APPLICATIO S I FOR ATIO GAIN A V –12dB/OCT 0 PHASE –6dB/OCT Figure 11. Transfer Function of Buck Modulator will stop, leaving 6dB/octave and 90° of phase shift (Figure 11). So far, the AC response of the loop ...
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... V in degrees. Refer to your SPICE manual for details of OUT how to generate this plot *3703 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 TYPE 2 Loop: ⎛ ⎞ BOOST = + ° K tan 45 ⎜ ⎟ ⎝ ⎠ π 2 • • • • ...
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LTC3703 U U APPLICATIO S I FOR ATIO 2 ⎛ ⎞ MAX = + δ ⎜ ⎟ MAIN MAX ⎝ ⎠ 1 – D MAX ⎛ ⎞ MAX V ...
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U U APPLICATIO S I FOR ATIO Once V is determined chosen as follows: PROG IMAX /12µA IMAX PROG Note that in a boost mode architecture only possible to provide protection for “soft” ...
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LTC3703 U U APPLICATIO S I FOR ATIO If RUN/SS starts at 0V, the delay before starting is approxi- mately DELAY START , SS µ plus an additional ...
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U U APPLICATIO S I FOR ATIO oscillator can synchronize to frequencies between 100kHz and 600kHz, independent of the frequency programmed by the R resistor. However recommended that an SET R resistor be chosen such that the frequency ...
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LTC3703 U U APPLICATIO S I FOR ATIO losses are predicted from the DC resistances of MOSFETs, the inductor and input and output capacitor ESR. In continuous mode, the average output current flows through L but ...
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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 U U APPLICATIO S I FOR ATIO And double check the assumed 70°C + (1.64W)(20°C/W) = 103°C J Since the synchronous MOSFET will be conducting over twice as long each period (almost 100% of the ...
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U U APPLICATIO S I FOR ATIO connection), staying away from any high dV/dt traces. Place the divider resistors near the LTC3703 in order to keep the high impedance FB node short. 8. For applications with multiple switching power convert- ...
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LTC3703 U TYPICAL APPLICATIO S 36V-72V Input Voltage to 5V/10A Step-Down Converter with Pulse Skip Mode Enabled R C1 10k 470pF 1000pF R MAX R2 C 21.5k 0.1µ 100Ω 113k C C3 ...
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... FLASH SHALL NOT EXCEED .254mm (.010") PER SIDE 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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... Switch, Automatic Step-Up/Step-Down, ≤ 60V, Voltage Mode, 1Ω Logic-Level MOSFET Drivers ≤ 60V, Current Mode, 1.23V ≤ V ≤ 36V OUT LT 0306 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2003 ≤ 20A ≤ 20A ≤ 20A OUT 3703fa ...