LTC3405A-1.8 Linear Technology, LTC3405A-1.8 Datasheet
LTC3405A-1.8
Related parts for LTC3405A-1.8
LTC3405A-1.8 Summary of contents
Page 1
... PCB footprint. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. The LTC3405A-1.5/LTC3405A-1.8 are available in a low profile (1mm) ThinSOT package. For adjustable output voltage, refer to the LTC3405A data sheet ...
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... GND PACKAGE 6-LEAD PLASTIC SOT- 125 C, JMAX Consult LTC Marketing for parts specified with wider operating temperature ranges. CONDITIONS 90%, Duty Cycle < 35% IN OUT LTC3405A-1.5, MODE = 3.6V LTC3405A-1.8, MODE = 3. – V OVL OVL OUT V = 2.5V to 5.5V IN (Note 90%, MODE = 3.6V OUT ...
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... G05 Output Voltage vs Load Current 1.834 1.824 1.814 Burst Mode OPERATION 1.804 1.794 PULSE SKIPPING MODE 1.784 1.774 0 100 200 300 400 500 LOAD CURRENT (mA) 3405A1518 G09 LTC3405A-1.5/LTC3405A-1.8 Efficiency vs Output Current 100 ...
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... LTC3405A-1.5/LTC3405A-1 TYPICAL PERFOR A CE CHARACTERISTICS (From Figure 1a) Dynamic Supply Current vs Supply Voltage 1800 V = 1.8V OUT 1600 LOAD 1400 1200 1000 800 600 400 PULSE SKIPPING MODE 200 BURST MODE OPERATION 0 2 2.5 3 3.5 5.5 4 4.5 5 SUPPLY VOLTAGE (V) 3405A1518 G12 Switch Leakage vs Input Voltage ...
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... In shutdown, all functions are disabled drawing <1 A supply current. Do not leave RUN floating. GND (Pin 2): Ground Pin. SW (Pin 3): Switch Node Connection to Inductor. This pin connects to the drains of the internal main and synchro- nous power MOSFET switches. LTC3405A-1.5/LTC3405A-1.8 Load Step V OUT 100mV/DIV AC ...
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... SLOPE COMP OSC FREQ SHIFT V OUT 5 R1 LTC3405A-1 110k 440k – LTC3405A-1 180k R2 = 360k V IN RUN 1.2V REF 1 – OVDET + 1.294V SHUTDOWN U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC3405A Fixed output voltage series parts use a constant frequency, current mode step-down architec- ture ...
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... The LTC3405A series parts will operate with input supply voltages as low as 2.5V, but the maximum allowable output current is reduced at this low voltage. Figure 2 shows the reduction in the maximum output current as a function of input voltage for both fixed output voltages. LTC3405A-1.5/LTC3405A-1.8 www.DataSheet4U.com 600 V = 1.5V ...
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... LTC3405A-1.5/LTC3405A-1 APPLICATIO S I FOR ATIO The basic LTC3405A series parts application circuit is shown in Figure 1. External component selection is driven by the load requirement and begins with the selection of L followed by C and OUT Inductor Selection For most applications, the inductor value will fall in the range of 2 ...
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... It is often useful to analyze individual losses to determine what is limiting the efficiency and which change would produce the most improvement. Efficiency can be expressed as: Efficiency = 100% – ( ...) LTC3405A-1.5/LTC3405A-1 where L1, L2, etc. are the individual losses as a percentage of input power. ...
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... where example, consider the LTC3405A-1.8 with an input voltage of 2.7V, a load current of 300mA and an ambient and the duty cycle temperature From the typical performance graph of switch resistance, the approximately 0.94 and the R )(1 – DC) DS(ON)BOT N-channel synchronous switch is approximately 0 ...
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... MOSFETs. 3. Keep the (–) plates of C and C IN OUT Design Example As a design example, assume the LTC3405A-1.8 is used in a single lithium-ion battery-powered cellular phone application. The V will be operating from a maximum of IN 4.2V down to about 2.7V. The load current requirement is a maximum of 0.25A but most of the time it will be in ...
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... LTC3405A-1.5/LTC3405A-1 APPLICATIO S I FOR ATIO 2.7V TO 4.2V AC COUPLED 6 LTC3405A-1.8 4 CER RUN 6 5 MODE V OUT GND *SUMIDA CMD4D11-6R8MC 2 ** TAIYO YUDEN JMK212BJ475MG 3405A1518 F06a Figure 6a. 100 100 OUTPUT CURRENT (mA) 3405A1518 F06b Figure 6b ...
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... U TYPICAL APPLICATIO 2.7V TO 4.2V AC COUPLED LTC3405A-1.5/LTC3405A-1.8 Single Li-Ion to 1.5V/300mA Regulator for High Efficiency and Small Footprint 4 LTC3405A-1.5 4 CER RUN 6 5 MODE V OUT GND 3405A1518 TA02a 2 * MURATA LQH32CN4R7M33 ** TAIYO YUDEN CERAMIC JMK212BJ475MG 100 ...
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... LTC3405A-1.5/LTC3405A-1.8 U TYPICAL APPLICATIO S Using All Ceramic Capacitors Optimized for Smallest Footprint V IN 2.7V TO 4.2V AC COUPLED 14 Single Li-Ion to 1.5V/150mA Regulator 2 LTC3405A-1.5 2 CER RUN 6 5 MODE V OUT GND 3405A1518 TA03a 2 * TAIYO YUDEN LB2012T2R2M ** TAIYO YUDEN CERAMIC LMK212BJ225MG 1.5V ...
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... 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. LTC3405A-1.5/LTC3405A-1 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 1 ...
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