LT1912EDD#PBF Linear Technology, LT1912EDD#PBF Datasheet

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... LT1912 is available in 10-pin MSOP and 3mm × 3mm DFN packages with exposed pads for low thermal resistance. L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners ...

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... JC EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT1912EDD#PBF LT1912EDD#TRPBF LT1912EMSE#PBF LT1912EMSE#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T noted. (Note 2) PARAMETER Feedback Voltage FB Pin Bias Current (Note 3) FB Voltage Line Regulation Error Amp g m Error Amp Gain V Source Current C V Sink Current C ...

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LT1912 TYPICAL PERFORMANCE CHARACTERISTICS Efficiency 100 V = 12V 34V 24V NEC PLC-0745-5R6 500kHz OUT 50 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 ...

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TYPICAL PERFORMANCE CHARACTERISTICS Feedback Voltage 840 820 800 780 760 –50 – 100 125 TEMPERATURE (°C) 1912 G09 Minimum Switch On-Time 140 120 100 –50 – 100 ...

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LT1912 TYPICAL PERFORMANCE CHARACTERISTICS V Voltages C 2.50 2.00 CURRENT LIMIT CLAMP 1.50 1.00 SWITCHING THRESHOLD 0.50 0 –50 – 100 125 TEMPERATURE (°C) 1912 G19 6 Switching Waveforms; Discontinuous Operation V SW 5V/DIV I L ...

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PIN FUNCTIONS BD (Pin 1): This pin connects to the anode of the boost Schottky diode. BD also supplies current to the internal regulator. BOOST (Pin 2): This pin is used to provide a drive voltage, higher than the input ...

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LT1912 OPERATION The LT1912 is a constant frequency, current mode step- down regulator. An oscillator, with frequency set by R enables an RS flip-flop, turning on the internal power switch. An amplifier and comparator monitor the current flowing between the ...

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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 R1= R2 – 1 ⎝ ⎜ ⎠ ⎟ ...

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LT1912 APPLICATIONS INFORMATION pulse-skipping operation where some switching pulses are skipped to maintain output regulation. In this mode the output voltage ripple and inductor current ripple will be higher than in normal operation. The minimum input voltage is determined by ...

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... For details of maximum output current and discontinuous mode opera- tion, see Linear Technology Application Note 44. Finally, for duty cycles greater than 50 minimum inductance required to avoid subharmonic oscillations. See AN19. ...

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LT1912 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 Catch Diode The catch diode conducts current only during switch off time. Average forward ...

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APPLICATIONS INFORMATION and in particular the type of output capacitor. A practical approach is to start with one of the circuits in this data sheet that is similar to your application and tune the com- pensation network to optimize the ...

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LT1912 APPLICATIONS INFORMATION 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 depend on input and output ...

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APPLICATIONS INFORMATION 6.0 5.5 TO START (WORST CASE) 5.0 4.5 4.0 TO RUN 3.5 3 3.3V OUT T = 25° 8.2µ 500kHz 2 100 LOAD CURRENT (A) 8.0 TO START ...

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... LT1912 circuits. However, these capaci- tors can cause problems if the LT1912 is plugged into a live supply (see Linear Technology Application Note 88 for a complete discussion). The low loss ceramic capacitor, combined with stray inductance in series with the power ...

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... AI.EI. Figure 9. A Well Chosen Input Network Prevents Input Voltage Overshoot and Ensures Reliable Operation when the LT1912 is Connected to a Live Supply Other Linear Technology Publications Application Notes 19, 35 and 44 contain more detailed descriptions and design information for buck regulators and other switching regulators. The LT1376 data sheet has a more extensive discussion of output ripple, loop compensation and stability testing ...

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LT1912 TYPICAL APPLICATIONS V IN 6.8V TO 36V 4.7µF 470pF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB6R8M V IN 4.4V TO 36V 4.7µF 470pF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB4R7M 18 5V Step-Down Converter ...

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TYPICAL APPLICATIONS 36V 4.7µF 330pF D1: DIODES INC. DFLS240L D2: MBR0540 L: TAIYO YUDEN NP06DZB4R7M 2.5V Step-Down Converter RUN/SS BOOST ON OFF LT1912 R T 20k 68.1k SYNC FB GND ...

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LT1912 TYPICAL APPLICATIONS V IN 15V TO 36V 10µF 26.1k 330pF D: DIODES INC. DFLS240L L: NEC/TOKIN PLC-0755-100 V IN 3.5V TO 27V 4.7µF 330pF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB3R3M 20 12V Step-Down Converter ...

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PACKAGE DESCRIPTION 3.55 ±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 DD Package 10-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # ...

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LT1912 PACKAGE DESCRIPTION 1.88 ± 0.102 (.074 ± .004) 5.23 (.206) (.066 ± .004) MIN 0.305 ± 0.038 (.0120 ± .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE DETAIL “A” 0.18 (.007) NOTE: 1. DIMENSIONS IN ...

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... Changed units to mA for Quiescent Current from V 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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... OUT(MIN 1.2V 100µA, I <1µA, OUT(MIN 0.79V 70µA, I <1µA, OUT(MIN 1.26V 50µA, I <1µA, OUT(MIN 1.26V 1.5mA, I <1µA, OUT(MIN 0.79V 450µA, I < 1µA, OUT(MIN 1110 REV A • PRINTED IN USA  LINEAR TECHNOLOGY CORPORA TION 2007 1912fa ...