lt3481imse-trpbf Linear Technology Corporation, lt3481imse-trpbf Datasheet
lt3481imse-trpbf
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lt3481imse-trpbf Summary of contents
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... V output voltage. The LT3481 is available in 10-Pin MSOP and 3mm x 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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... Not Switching BIAS V = 0.2V RUN/ 3V, Not Switching BIAS Not Switching BIAS ORDER PART NUMBER 10 RT LT3481EMSE LT3481IMSE BIAS 6 PG MSE PART MARKING LTBVT = 45°C/W, θ = 10°C/W JC LTBVW = 15V 3.3V unless otherwise BOOST BIAS MIN TYP MAX ● ...
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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 GM Error Amp Gain V Source Current C V ...
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LT3481 W U TYPICAL PERFOR A CE CHARACTERISTICS Effi ciency (V = 5.0V) OUT 100 12V 24V NEC PLC-0745-4R7 10 f: 800kHz 0 0.0001 0.001 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Switch Voltage Drop 700 600 500 400 300 200 100 0 0 500 1000 1500 2000 2500 3000 3500 SWITCH CURRENT (mA) 3481 G10 Switching Frequency 1. 45.3kΩ T 1.15 1.10 ...
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LT3481 W U TYPICAL PERFOR A CE CHARACTERISTICS Error Amp Output Current 100 –20 –40 –60 –80 1.065 1.165 1 .265 1.365 1.465 FB PIN VOLTAGE (V) 3481 G19 V Voltages C 2.50 2.00 CURRENT ...
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CTIO S 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 ...
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LT3481 OPERATION The LT3481 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 ...
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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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LT3481 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 ...
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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. If ...
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LT3481 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 ...
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APPLICATIONS INFORMATION A fi nal precaution regarding ceramic capacitors concerns the maximum input voltage rating of the LT3481. A ceramic input capacitor combined with trace or cable inductance forms a high quality (under damped) tank circuit. If the LT3481 circuit ...
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LT3481 APPLICATIONS INFORMATION Burst Mode Operation To enhance effi ciency at light loads, the LT3481 auto- matically switches to Burst Mode operation which keeps the output capacitor charged to the proper voltage while minimizing the input quiescent current. During Burst ...
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APPLICATIONS INFORMATION may not be fully charged. Because the boost capacitor is charged with the energy stored in the inductor, the circuit will rely on some minimum load current to get the boost circuit running properly. This minimum load will ...
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LT3481 APPLICATIONS INFORMATION from maximum value given by the following equation: ⎛ OUT = DC 1 – ⎝ ⎜ SYNC MAX + V – where V is the ...
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APPLICATIONS INFORMATION OUT GND VIAS TO LOCAL GROUND PLANE VIAS TO RUN/SS VIAS TO V VIAS TO PG OUT Figure 9. A Good PCB Layout Ensures Proper, Low EMI Operation + LOW IMPEDANCE ...
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LT3481 APPLICATIONS INFORMATION fi rst plot is the response with a 4.7µF ceramic capacitor at the input. The input voltage rings as high as 50V and the input current peaks at 26A. A good solution is shown in Figure 10b. ...
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TYPICAL APPLICATIONS V IN 4.4V TO 34V 4.7µF 16.2k 330pF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB4R7M 34V 4.7µF 22.1k 220pF D1: DIODES INC. DFLS240L D2: MBR0540 L: TAIYO YUDEN NP06DZB4R7M V IN 8.6V TO ...
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LT3481 TYPICAL APPLICATIONS V IN 15V TO 34V 10µF 330pF D: DIODES INC. DFLS240L L: NEC/TOKIN PLC-0755-100 V IN 20V TO 34V 4.7µF NOTE: DO NOT APPLY SYNC SIGNAL UNTIL PGOOD GOES HIGH SYNC IN 3.3V SQ WAVE 300kHz TO ...
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TYPICAL APPLICATIONS 1k SYNC IN 3.3V SQ WAVE 360kHz TO 450kHz 25k Q1 25k 50pF V IN 3.5V TO 27V 4.7µF 330pF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB3R3M 5V Step-Down Converter with Sync and One-Shot ...
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LT3481 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 Package 10-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # ...
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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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... TSSOP16E 25 1.20V 1mA <6µA 25 1.20V 3.8mA <30µA TSSOP16E 60V 1.20V 2.5mA 25µA TSSOP16E 60V 1.20V 100µA <1µA TSSOP16E LT 0406 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2006 PACKAGE ThinSOT DFN MS8E DFN MS8E 3481f ...