lt3684emse-trpbf Linear Technology Corporation, lt3684emse-trpbf Datasheet
lt3684emse-trpbf
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lt3684emse-trpbf Summary of contents
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... The LT3684 is available in 10-Pin MSOP and 3mm × 3mm DFN packages with Exposed Pads for low thermal resistance. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. V OUT 3 ...
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... BIAS 6 PG EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB = 10°C/W JC ORDER PART NUMBER LCVT LT3684EMSE LCVT LT3684IMSE ● The denotes the specifi cations which apply over the full operating = 25° 10V RUNS/SS CONDITIONS V = 0.2V RUN/SS V ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T noted. (Note 2) PARAMETER Minimum Bias Voltage Feedback Voltage FB Pin Bias Current (Note 3) FB Voltage Line Regulation Error Amp g m Error Amp Gain V Source Current C ...
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LT3684 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency (V = 5.0V) OUT 100 V = 12V 24V NEC PLC-0745-4R7 f = 800kHz 50 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Feedback Voltage 1.290 1.285 1.280 1.275 1.270 1.265 1.260 1.255 1.250 –50 – 100 TEMPERATURE (°C) 3684 G10 Minimum Switch On-Time 140 120 100 –50 – ...
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LT3684 TYPICAL PERFORMANCE CHARACTERISTICS Minimum Input Voltage 6.5 6.0 5.5 5 OUT 4 25° 4.7µ 800kHz 4.0 0.1 0.001 0.01 1 LOAD CURRENT (A) 3684 G19 Switching Waveforms (Discontinuous Operation) ...
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PIN FUNCTIONS BD (Pin 1): This pin connects to the anode of the boost Schottky diode. BOOST (Pin 2): This pin is used to provide a drive voltage, higher than the input voltage, to the internal bipolar NPN power switch. ...
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LT3684 BLOCK DIAGRAM BIAS INTERNAL 1.265V REF 7 RUN/ SOFT-START PG 6 ERROR AMP + 1.12V – GND – + Σ SLOPE COMP ...
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OPERATION The LT3684 is a constant frequency, current mode step- down regulator. An oscillator, with frequency set by RT, enables an RS fl ip-fl op, turning on the internal power switch. An amplifi er and comparator monitor the current fl ...
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LT3684 APPLICATIONS INFORMATION FB Resistor Network The output voltage is programmed with a resistor divider between the output and the FB pin. Choose the 1% resis- tors according to: ⎛ ⎞ V OUT = – 1 ...
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APPLICATIONS INFORMATION frequency will be necessary to achieve safe operation at high input voltages. If the output is in regulation and no short-circuit or start-up events are expected, then input voltage transients 36V are acceptable regardless of ...
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LT3684 APPLICATIONS INFORMATION Of course, such a simple design guide will not always re- sult in the optimum inductor for your application. A larger value inductor provides a slightly higher maximum load current and will reduce the output voltage ripple. ...
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APPLICATIONS INFORMATION Table 2. Capacitor Vendors VENDOR PHONE Panasonic (714) 373-7366 Kemet (864) 963-6300 Sanyo (408) 749-9714 Murata (408) 436-1300 AVX Taiyo Yuden (864) 963-6300 When choosing a capacitor, look carefully through the data sheet to fi nd out what ...
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LT3684 APPLICATIONS INFORMATION LT3684 CURRENT MODE SW POWER STAGE ERROR g = 3.5mho m R1 AMPLIFIER FB – 330µmho + 1.265V 3M V GND Figure 2. Model for Loop ...
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APPLICATIONS INFORMATION BD BOOST LT3684 GND 4.7µF (4a) For V > 2.8V OUT BD BOOST LT3684 GND 4.7µF (4b) For 2.5V < V OUT BD BOOST V V ...
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LT3684 APPLICATIONS INFORMATION Soft-Start The RUN/SS pin can be used to soft-start the LT3684, reducing the maximum input current during start-up. The RUN/SS pin is driven through an external RC fi lter to create a voltage ramp at this pin. ...
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APPLICATIONS INFORMATION VIAS TO LOCAL GROUND PLANE VIAS TO V Figure 8. A Good PCB Layout Ensures Proper, Low EMI Operation Hot Plugging Safely The small size, robustness and low impedance of ceramic capacitors make them an attractive option for ...
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LT3684 APPLICATIONS INFORMATION CLOSING SWITCH SIMULATES HOT PLUG + LOW IMPEDANCE ENERGIZED 24V SUPPLY + 0.1µF + 22µF 35V AI.EI. Figure 9. A Well Chosen Input Network Prevents Input Voltage Overshoot and Ensures Reliable Operation when the LT3684 is Connected ...
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TYPICAL APPLICATIONS V IN 6.3V TO 34V 4.7µF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB6R8M V IN 4.4V TO 34V 4.7µF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB4R7M 5V Step-Down Converter RUN/SS BOOST ON OFF ...
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LT3684 TYPICAL APPLICATIONS 34V 4.7 F D1: DIODES INC. DFLS240L D2: MBR0540 L: TAIYO YUDEN NP06DZB4R7M V IN 8.6V TO 22V TRANSIENT TO 36V D: DIODES INC. DFLS240L L: SUMIDA CDRH4D22/HP-2R2 20 2.5V Step-Down Converter V ...
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TYPICAL APPLICATIONS V IN 15V TO 34V 10µF D: DIODES INC. DFLS240L L: NEC/TOKIN PLC-0755-100 V IN 3.5V TO 27V D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB3R3M 12V Step-Down Converter RUN/SS BOOST ON OFF V SW ...
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LT3684 PACKAGE DESCRIPTION 3.50 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF 22 DD Package 10-Lead Plastic DFN (3mm × 3mm) (Reference LTC ...
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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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... I < 30µA, TSSOP16E OUT(MIN 1.20V 2.5mA, I < 25µA, TSSOP16E OUT(MIN 1.20V 100µA, I < 1µA, TSSOP16E OUT(MIN < 1µA, 3mm × 3mm = 1.265V 5µA, I OUT(MIN 0207 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2007 TM 3684f ...