LM2704MFX-ADJ/NOPB National Semiconductor, LM2704MFX-ADJ/NOPB Datasheet
LM2704MFX-ADJ/NOPB
Specifications of LM2704MFX-ADJ/NOPB
Available stocks
Related parts for LM2704MFX-ADJ/NOPB
LM2704MFX-ADJ/NOPB Summary of contents
Page 1
... LCD panels requiring low current and high efficiency as well as white LED applications for cellular phone back-lighting. The LM2704 can drive white LEDs from a single Li-Ion battery. © 2003 National Semiconductor Corporation Features n 550mA, 0.7Ω, internal switch n Uses small surface mount components n Adjustable output voltage up to 20V n 2 ...
Page 2
... Connection Diagram Ordering Information Order Number Package Type LM2704MF-ADJ SOT23-5 LM2704MFX-ADJ SOT23-5 Pin Description/Functions Pin Name GND SHDN SW(Pin 1): Switch Pin. This is the drain of the internal NMOS power switch. Minimize the metal trace area con- nected to this pin to minimize EMI. GND(Pin 2): Ground Pin. Tie directly to ground plane. ...
Page 3
... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications Voltage FB Voltage SHDN Voltage Maximum Junction Temp (Note 2) Lead Temperature (Soldering 10 sec.) Vapor Phase (60 sec.) Electrical Characteristics Specifications in standard type face are for T Range (T = − ...
Page 4
Typical Performance Characteristics Enable Current vs V (Part Switching) Efficiency vs Load Current www.national.com IN 20031505 20031510 4 Disable Current (Part Not Switching) 20031506 Efficiency vs Load Current 20031511 ...
Page 5
Typical Performance Characteristics Efficiency vs Load Current Switch Current Limit vs V (Continued) 20031512 IN 20031514 5 SHDN Threshold 20031513 Switch DSON IN 20031515 www.national.com ...
Page 6
Typical Performance Characteristics FB Trip Point and FB Pin Current vs Temperature Step Response V = 20V 3.0V OUT IN 1) Load, 1mA to 17mA to 1mA 200mV/div, AC OUT 500mA/div, ...
Page 7
Operation V = 20V 2.5V OUT 20V/div Inductor Current, 500mA/div 100mV/div, AC OUT T = 10µs/div FIGURE 2. LM2704 Block Diagram FIGURE 3. Typical Switching Waveform 7 ...
Page 8
Operation (Continued) The LM2704 features a constant off-time control scheme. Operation can be best understood by referring to Figure 2 and Figure 3. Transistors Q1 and Q2 and resistors R3 and R4 of Figure 2 form a bandgap reference used ...
Page 9
Application Information (Continued) FIGURE 4. White LED Application FIGURE 5. Li-Ion 5V Application FIGURE 6. Li-Ion 12V Application 9 20031509 20031534 20031535 www.national.com ...
Page 10
Application Information www.national.com (Continued) FIGURE 12V Application 10 20031536 ...
Page 11
... NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...