LM3661TL-1.25 NSC [National Semiconductor], LM3661TL-1.25 Datasheet
LM3661TL-1.25
Related parts for LM3661TL-1.25
LM3661TL-1.25 Summary of contents
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LM3661 450mA Subminiature, Micropower Step-Down DC-DC Converter for Ultra Low-Voltage Circuits General Description The LM3661 step-down DC-DC converter is optimized for powering ultra-low voltage circuits from a single Lithium-Ion cell. The device provides two pin-selectable output voltages. See ordering information ...
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Block Diagram www.national.com FIGURE 1. Simplified Functional Diagram 2 20098801 ...
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... Connection Diagrams 10-Bump micro SMD Package Top View Ordering Information Order Number Output Voltage LM3661TLX - 1.25 1.05V/1.25V LM3661TL - 1.25 LM3661TLX - 1.35 1.05V/1.35V LM3661TL - 1.35 LM3661TLX - 1.40 1.05V/1.40V LM3661TL - 1.40 Pin Description Pin Number Name SEL C1 I SEL D1 SYNC/MODE PGND ...
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Pin Description (Continued) Pin Number Name SGND www.national.com Function Analog Supply Input. Analog and Control Ground. 4 ...
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... SEL LM3661TL-1.25 SEL IN LM3661TL-1.35 SEL LM3661TL-1.35 SEL IN LM3661TL-1.40 SEL LM3661TL-1.40 SEL IN LM3661TL-1.25 SEL = 1mA LM3661TL-1.25 SEL IN LM3661TL-1.35 SEL LM3661TL-1.35 SEL IN LM3661TL-1. SEL LM3661TL-1. SEL IN SYNC/MODE = 2.7V to 5.5V IN SYNC/MODE = ...
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Electrical Characteristics Specifications with standard typeface are for T Range ( −30˚C to +85˚C). Unless otherwise specified µF. OUT Symbol Parameter V EN Logic High Input (Note 4) EN ...
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Typical Performance Characteristics otherwise noted) Quiescent Supply Current vs. Supply Voltage (PWM MODE) Output Voltage vs. Output Current (PWM MODE, I =L, V SEL OUT Output Voltage vs. Output Current (LDO MODE, V =1.05V) OUT (Circuit in Fig.2, PV Quiescent ...
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Typical Performance Characteristics otherwise noted) (Continued) Output Voltage vs. Supply Voltage (PWM MODE SEL Output Voltage vs. Supply Voltage (LDO MODE, V OUT Switching Frequency vs. Temperature (PWM MODE, SYNC/MODE = V www.national.com (Circuit in Fig.2, ...
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Typical Performance Characteristics otherwise noted) (Continued) Efficiency vs. Output Current (PWM MODE SEL OUT LDO Load Transient Response (V = 3.6V & 1.35V) IN OUT PWM Start-up Respsonse (V = 3.6V & ...
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Typical Performance Characteristics otherwise noted) (Continued) LDO Start-up Respsonse (V = 3.6V & OUT V Transition in PWM Mode SEL (LM3661-1.35) V & SYNC/MODE Transition in PWM Mode SEL www.national.com (Circuit in Fig. 1.05V) 20098842 20098847 ...
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Typical Performance Characteristics otherwise noted) (Continued) TYP Waveform (PWM Mode 450mA) OUT External SYNC/MODE at 600kHz ( I = 450mA ) OUT (Circuit in Fig. EN=3.6V External SYNC/MODE at 600kHz ( ...
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Circuit Operation The LM3661 operates as follows: During the first part of each switching cycle, the control block in the LM3661 turns on the internal PFET switch. This allows current to flow from the input through the inductor to the ...
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Frequency Synchronization (Continued) over/undershoot. Note that sharp edged signals from a pulse or function generator can develop under/overshoot as high as 10V at the end of an improperly terminated cable. Over-voltage Protection The LM3661 has an over-voltage comparator that prevents ...
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Application Information INDUCTOR SELECTION There are a few things that one must consider when select- ing an inductor for an application. They are the inductor DC current rating, inductor ripple current, DC-resistance of the inductor and value of the inductor. ...
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Application Information to perform these functions. The ESR, or equivalent series resistance, of the filter capacitors is a major factor in voltage ripple. Table 3 lists suggested capacitors suppliers. Table 3. Suggested capacitors and Suppliers Model Size (EIA) Input Filter ...
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Physical Dimensions NOTES: UNLESS OTHERWISE SPECIFIED 1. EPOXY COATING 2. 63Sn/37Pb EUTECTIC BUMP 3. RECOMMEND NON-SOLDER MASK DEFINED LANDING PAD. 4. PIN A1 IS ESTABLISHED BY LOWER LEFT CORNER WITH RESPECT TO TEXT ORIENTATION. REMAINING PINS ARE NUMBERED COUNTER CLOCKWISE. ...
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National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. For the most current product information ...