LM3678SD-1.2/NOPB National Semiconductor, LM3678SD-1.2/NOPB Datasheet
LM3678SD-1.2/NOPB
Specifications of LM3678SD-1.2/NOPB
Available stocks
Related parts for LM3678SD-1.2/NOPB
LM3678SD-1.2/NOPB Summary of contents
Page 1
... A high switching frequency of 3.3MHz (typ.) allows use of tiny surface-mount components. Only three external surface- mount components, an inductor and two ceramic capacitors, are required (solution size less than 33 mm other than the voltage shown, please refer to ordering infor- mation section or contact National Semiconductor. Typical Application Circuit Note 1.2V 0.8V ...
Page 2
Functional Block Diagram www.national.com FIGURE 2. LM3678 Block Diagram 2 20204505 ...
Page 3
... DAP Ordering Information Voltage Option Order Number LM3678SDE-1.2 0.8V/1.2V LM3678SD-1.2 LM3678SDX-1.2 20204502 Description Power Ground pin. Analog Ground Pin Switching node connection to the internal PFET switch and NFET synchronous rectifier Analog supply input. Connect to the input filter capacitor (Figure 1). Power supply Input. Connect to the input filter capacitor (Figure 1). ...
Page 4
... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. V Pin: Voltage to GND IN EN Pin: FB, SW Pin: Continuous Power Dissipation (Note 3) Junction Temperature (T ) J-MAX Electrical Characteristics apply over the full operating ambient temperature range (−30°C the LM3678 Typical Application Circuit (pg ...
Page 5
... Typical Performance Characteristics LM3678SD, Circuit of Figure 3.6V Quiescent Supply Current vs. Temperature NFET_ R vs. Temperature DSON ILIMIT vs. Temperature (Open Loop) = 1.2V 10µ 22µF, and T OUT IN OUT Switching Frequency vs. Temperature 20204533 PFET_R 20204536 Efficiency PWM Mode vs. ILOAD (0.8V) 20204538 5 = 25°C, unless otherwise noted. ...
Page 6
Efficiency PWM Mode vs. ILOAD (1.2V) Line Transient Response (V = 1.2V, LOAD = 500mA) OUT Load Transient Response (V = 3.6V 0.8V, Load Step 0 IN OUT www.national.com Line Transient Response (V OUT 20204523 Load Transient Response ...
Page 7
Load Transient Response (V = 3.6V 1.2V, Load Step 500mA IN OUT VSELECT Transient Response (V = 3.6V, No LOAD) IN Start 3.6V 1.2V, LOAD = 1A) IN OUT VSELECT Transient Response ↔ ...
Page 8
Switching Waveform (V = 1.2V, LOAD = 1A) OUT www.national.com 20204556 8 ...
Page 9
Operation Description DEVICE INFORMATION The LM3678, 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 2.5V to 5.5V to portable devices such as cell phones ...
Page 10
Inductor Selection There are two main considerations when choosing an induc- tor; the inductor should not saturate, and the inductor current ripple should be small enough to achieve the desired output voltage ripple. Different saturation current rating specifica- tions are ...
Page 11
TABLE 2. Suggested Capacitors and Their Suppliers Model Type 10µF for C IN GRM21BR60J106K Ceramic, X5R JMK212BJ106K Ceramic, X5R C2012X5R0J106K Ceramic, X5R 22µF for C OUT JMK212BJ226MG Ceramic, X5R Board Layout Considerations PC board layout is an important part of ...
Page 12
Physical Dimensions www.national.com inches (millimeters) unless otherwise noted Non Pullback LLP-10, 0.5mm Pitch NS Package Number SDA10A The dimensions for X1, X2, and X3 are as given 3mm +/- 0.030mm X2 = 3mm +/- 0.030mm X3 = 0.800mm ...
Page 13
Notes 13 www.national.com ...
Page 14
... For more National Semiconductor product information and proven design tools, visit the following Web sites at: Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock and Timing www.national.com/timing Data Converters www.national.com/adc Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www.national.com/ldo LED Lighting www ...