LT3437IFE#TRPBF Linear Technology, LT3437IFE#TRPBF Datasheet
LT3437IFE#TRPBF
Specifications of LT3437IFE#TRPBF
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LT3437IFE#TRPBF Summary of contents
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... Battery-Powered Systems ■ Powered Ethernet , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. *Protected by U.S. Patents, including 6498466. **See Burst Mode Operation section for conditions. ...
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LT3437 ABSOLUTE AXI U RATI GS (Note SHDN, BIAS, SW Operating ............................. 60V SHDN 100ms Transient, <15% Duty Cycle ....... 80V IN BOOST Pin Above SW ............................................ 35V BOOST Pin Voltage ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T otherwise noted. SYMBOL PARAMETER I Supply Quiescent Current VIN Minimum BIAS Voltage (Note 5) I BIAS Sleep Current (Note 4) BIASS I BIAS Quiescent Current BIAS Minimum Boost Voltage (Note 6) ...
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LT3437 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T otherwise noted. I Supply Quiescent Current VIN Minimum BIAS Voltage (Note 5) I BIAS Sleep Current (Note 4) BIASS I BIAS Quiescent Current BIAS Minimum Boost Voltage (Note 6) Input ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency and Power Loss vs Load Current 100 V = 12V 3.3V 90 OUT T = 25° EFFICIENCY POWER LOSS ...
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LT3437 W U TYPICAL PERFOR A CE CHARACTERISTICS Soft-Start Current Threshold vs FB Voltage 35 SOFT-START DEFEATED 0.2 0.6 0.8 1.0 0.4 FB VOLTAGE (V) 3437 G10 Supply Current vs Input Voltage ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Dropout Operation OUT I = 250mA LOAD BOOST DIODE = DIODES INC B1100 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 INPUT ...
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LT3437 CTIO S (DD/FE) SW (Pin 1/Pin 2): The SW pin is the emitter of the on-chip power NPN switch. This pin is driven up to the input pin voltage during switch on time. Inductor ...
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CTIO S (DD/FE) BIAS (Pin 6/Pin 10): The BIAS pin is used to improve efficiency when operating at higher input voltages and light load current. Connecting this pin to the regulated output voltage forces most ...
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LT3437 W BLOCK DIAGRA V IN UNDERVOLTAGE BIAS SYNC SHDN + SHDN COMP – 1. – + 1.25V V C The LT3437 is a constant frequency, current mode buck converter. This means that there is an internal ...
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U U APPLICATIO S I FOR ATIO FEEDBACK PIN FUNCTIONS The feedback (FB) pin on the LT3437 is used to set output voltage and provide several overload protection features. The first part of this section deals with selecting resistors to ...
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LT3437 U U APPLICATIO S I FOR ATIO high input current surge during start-up. The soft-start function reduces input current surge by regulating switch current via the V pin to maintain a constant voltage ramp C rate (dV/dt) at the ...
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U U APPLICATIO S I FOR ATIO voltage could be unacceptable. Table 2 shows some typical solid tantalum surface mount capacitors. Table 2. Surface Mount Solid Tantalum Capacitor ESR and Ripple Current E CASE SIZE ESR MAX (Ω) AVX TPS ...
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LT3437 U U APPLICATIO S I FOR ATIO V OUT 10mV/DIV 100µF TANTALUM ESR 75mΩ V OUT 10mV/DIV 100µF CERAMIC V SW 10V/DIV V = 12V 1µs/DIV 3.3V OUT I = 500mA LOAD L = 100µH Figure ...
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... After making an initial choice, consider the secondary things like output voltage ripple, second sourcing, etc. Use the experts in Linear Technology’s applications department if you feel uncertain about the final choice. ). They have experience with a wide range of inductor ...
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LT3437 U U APPLICATIO S I FOR ATIO Short-Circuit Considerations The LT3437 is a current mode controller. It uses the V node voltage as an input to a current comparator which turns off the output switch on a cycle-by-cycle basis ...
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U U APPLICATIO S I FOR ATIO Burst Mode OPERATION To enhance efficiency at light loads, the LT3437 automati- cally switches to Burst Mode operation which keeps the output capacitor charged to the proper voltage while minimizing the input quiescent ...
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LT3437 U U APPLICATIO S I FOR ATIO These requirements result in the use of a Schottky type diode. DC switching losses are minimized due to its low forward voltage drop, and AC behavior is benign due to its lack ...
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U U APPLICATIO S I FOR ATIO SHUTDOWN FUNCTION AND UNDERVOLTAGE LOCKOUT The SHDN pin on the LT3437 controls the operation of the IC. When the voltage on the SHDN pin is below the 1.3V shutdown threshold, the LT3437 is ...
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LT3437 U U APPLICATIO S I FOR ATIO LAYOUT CONSIDERATIONS As with all high frequency switchers, when considering layout, care must be taken in order to achieve optimal electrical, thermal and noise performance. For maximum efficiency, switch rise and fall ...
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U U APPLICATIO S I FOR ATIO FE Package Topside Metal W U Figure 9. Suggested Layouts LT3437 3437 F09b DD Package Topside Metal 3437fc 21 ...
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LT3437 U U APPLICATIO S I FOR ATIO THERMAL CALCULATIONS Power dissipation in the LT3437 chip comes from four sources: switch DC loss, switch AC loss, boost circuit current, and input quiescent current. The following formu- las show how to ...
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U U APPLICATIO S I FOR ATIO increase in internal dissipation is of insufficient time dura- tion to raise die temperature significantly. A second consideration is controllability. A potential limi- tation occurs with a high step-down ratio ...
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LT3437 U U APPLICATIO S I FOR ATIO A zero can be added into the loop by placing a resistor (R at the V pin in series with the compensation capacitor placing a capacitor (C ) ...
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PACKAGE DESCRIPTIO 3.50 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 0.50 BSC 2.38 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2). CHECK ...
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LT3437 PACKAGE DESCRIPTIO 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE ...
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... SOME RESTRICTIONS MAY APPLY 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. 14V to 3.3V Step-Down Converter with 100µ ...
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... TSSOP-16E IN OUT 3.3V to 60V 100µA, I < 1µA, TSSOP-16E 40V 1.25V 26µA, ThinSOT IN OUT(MIN 36V 0.8V 670µ OUT(MIN QFN-32, SSOP-28 LT 0107 REV C • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2005 < 15µA, < 6µA, < 1µA, SD < 20µA, 3437fc ...