LM3677TL-1.8EV National Semiconductor, LM3677TL-1.8EV Datasheet
LM3677TL-1.8EV
Specifications of LM3677TL-1.8EV
Related parts for LM3677TL-1.8EV
LM3677TL-1.8EV Summary of contents
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... Only three external surface-mount components, an inductor and two ceramic capacitors, are required. Typical Application Circuits FIGURE 1. Typical Application Circuit FIGURE 2. Typical Application Circuit - ADJ. Version © 2008 National Semiconductor Corporation Features ■ 16 µA typical quiescent current ■ 600 mA maximum load capability ■ ...
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... GND Ordering Information Order Number Spec LM3677TL-1.2 (Note 1) NOPB LM3677TLX-1.2 (Note 1) NOPB LM3677TL-1.3 NOPB LM3677TLX-1.3 NOPB LM3677TL-1.5 NOPB LM3677TLX-1.5 NOPB www.national.com FIGURE 3. 5 Bump Micro SMD Package FIGURE 4. 6 Pin LLP Package Description Power supply input. Connect to the input filter capacitor (Figure 1). ...
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... Order Number Spec LM3677TL-1.8 NOPB LM3677TLX-1.8 NOPB LM3677TL-1.875 NOPB LM3677TLX-1.875 NOPB LM3677TL-2.5 NOPB LM3677TLX-2.5 NOPB LM3677TL-ADJ NOPB LM3677TLX-ADJ NOPB LM3677LEE-1.2 NOPB LM3677LE-1.2 NOPB LM3677LEX-1.2 NOPB LM3677LEE-1.5 NOPB LM3677LE-1.5 NOPB LM3677LEX-1.5 NOPB LM3677LEE-1.8 NOPB LM3677LE-1.8 NOPB LM3677LEX-1.8 NOPB LM3677LEE-1.82 NOPB LM3677LE-1.82 NOPB LM3677LEX-1 ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributor for availability and specifications. V Pin: Voltage to GND IN FB, SW, EN Pin: ...
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Dissipation Rating Table θ JA 85°C/W (4-layer board) micro SMD 117°C/W (4-layer board) LLP ≤ 60°C T 25° Power Rating Power Rating 1178 mW 785 mW 855 mW 556 85°C A Power ...
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Block Diagram www.national.com FIGURE 5. Simplified Functional Diagram 6 30008418 ...
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Typical Performance Characteristics LM3677, Circuit of Figure 3.6V Quiescent Supply Current vs. Supply Voltage (Switching) Switching Frequency vs. Temperature Open/Closed Loop Current Limit vs. Temperature = 1.8V 25°C, unless otherwise noted. OUT A ...
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Output Voltage vs. Supply Voltage (V = 2.5V) OUT Output Voltage vs. Temperature (V = 1.8V) OUT Output Voltage vs. Output Current (V = 1.8V) OUT www.national.com Output Voltage vs. Temperature 30008438 Output Voltage vs. Temperature 30008485 Output Voltage vs. ...
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Efficiency vs. Output Current (V = 1.3V) OUT Efficiency vs. Output Current (V = 2.5V) OUT Output Current vs. Input Voltage at Mode Change Point (V = 1.8V) OUT Efficiency vs. Output Current 30008441 Output Current vs. Input Voltage at ...
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Line Transient Response V = 1.3V (PWM Mode) OUT Line Transient Response V = 1.8V (PWM Mode) OUT Load Transient Response (V (PFM Mode 1mA to 50mA) www.national.com 30008433 30008478 = 1.3V) Load Transient Response (V OUT 30008493 10 Line ...
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Load Transient Response (V = 1.8V) OUT (PFM Mode 1mA to 50mA) Load Transient Response (V = 2.5V) OUT (PFM Mode 1mA to 50mA) Mode Change by Load Transients V = 1.3V (PFM to PWM) OUT Load Transient Response (V ...
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Mode Change by Load Transients V = 1.8V (PFM to PWM) OUT Load Transient Response V = 1.3V (PWM Mode) OUT Load Transient Response V = 2.5V (PWM Mode) OUT www.national.com Mode Change by Load Transients V = 1.8V (PWM ...
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Start Up into PFM Mode V = 1.3V (Output Current= 1mA) OUT Start Up into PFM Mode V = 1.8V (Output Current= 1mA) OUT Start Up into PFM Mode V = 2.5V (Output Current= 1mA) OUT Start Up into PWM ...
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Operation Description DEVICE INFORMATION The LM3677, a high-efficiency step-down DC-DC switching buck converter, delivers a constant voltage from a single Li- Ion battery and input voltage rails from 2.7V to 5.5V to devices such as cell phones and PDAs. Using ...
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FIGURE 7. Typical PFM Operation During PFM operation, the converter positions the output volt- age slightly higher than the nominal output voltage during PWM operation allowing additional headroom for voltage drop during a load transient from light to heavy load. ...
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Application Information INDUCTOR SELECTION There are two main considerations when choosing an induc- tor: the inductor should ...
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Model MIPSA2520D 1R0 LQM2HP 1R0 BRL2518T1R0M OUTPUT CAPACITOR SELECTION A ceramic output capacitor of 10 µF, 6.3V is sufficient for most applications. Use X7R or X5R types; do not use Y5V. DC bias characteristics of ceramic capacitors must be considered ...
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OUTPUT VOLTAGE SELECTION FOR LM3677-ADJ The output voltage of the adjustable parts can be pro- grammed through the resistor network connected from GND. The resistor and FB to GND (R kΩ to keep the current drawn ...
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... Use Use of the micro SMD package requires specialized board layout, precision mounting and careful re-flow techniques, as detailed in National Semiconductor Application Note 1112. Refer to the section "Surface Mount Technology (SMD) As- sembly Considerations". For best results in assembly, align- ment ordinals on the PC board should be used to facilitate placement of the device ...
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Special care must be given to place the input filter capacitor very close to the V 3. Arrange the components so that the switching current loops curl in the same direction. During the first half of each cycle, ...
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Physical Dimensions inches (millimeters) unless otherwise noted 5-Bump (Large) Micro SMD Package, 0.5 mmPitch The dimensions for X1, X2, and X3 are as given: NS Package Number TLA05FEA X1 = 1.107 mm +/- 0.030 1.488 mm +/- ...
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LLP Package, 0.5 mm Pitch NS Package Number LEB06A The dimensions for A, B, and C are as given 2.0 mm +/- 0 1.5 mm +/- 0 0.60 mm +/- ...
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Notes 23 www.national.com ...
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