lm2707 National Semiconductor Corporation, lm2707 Datasheet
lm2707
Related parts for lm2707
lm2707 Summary of contents
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... LEDs with forward currents between 0 and 40mA. LED brightness can be adjusted dynamically simply by applying a PWM signal to the enable (EN) pin. The PWM signal can be as fast as 50kHz because the LM2707 has a fast turn-on time. In addition to LED-drive applications, the LM2707 can also be used as a general purpose DC-DC voltage regulator in boost converter applications ...
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... Output Voltage Feedback. Reference Voltage is 0.515V (typ.) 6 GND Ground 7 C Oscillator Frequency Adjustment Active-High Enable Pin LM2707 is ON when V(EN) is above 1.2V LM2707 is Shutdown when V(EN) is below 0.3V Order Information Order Number Package Marking LM2707MF S0TB LM2707MFX S0TB www.national.com 8-Pin SOT23 Package National Semiconductor Package Number MF08A ...
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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 FB, and EN pins IN SW and V pins OVP Continuous Power Dissipation ...
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Electrical Characteristics Unless otherwise specified 3.0V Symbol Parameter Open Circuit Protection Section (V OVP V Output Over-Voltage Protection OVP (Open Circuit Pin Input Current OVP OVP Input Voltage Section (V pin Undervoltage ...
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Typical Performance Characteristics (Coilcraft DT1608C-223 MBR0520L (Vishay), C Oscillator Frequency vs. Temperature C = 10pF X Oscillator Period vs. Cx Capacitance Maximum Duty Cycle vs. Temperature C = 10pF X Unless otherwise specified 1.0µ ...
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Typical Performance Characteristics (Coilcraft DT1608C-223 MBR0520L (Vishay), C Feedback Trip Point vs. Supply Voltage Switch Resistance (R ) vs. Switch Current DS-ON Pin 1-2 Resistance vs. Temperature www.national.com Unless otherwise specified 1.0µ 2x1µF, C ...
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Typical Performance Characteristics (Coilcraft DT1608C-223 MBR0520L (Vishay), C Shutdown Supply Current vs. Supply Voltage Supply Current vs. EN Input Voltage EN Threshold vs. Supply Voltage Unless otherwise specified 1.0µ 2x1µ 68pF, T ...
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... A 1Ω resistor was placed between the V and L IN Note 11: LED drive efficiency is the ratio of the power consumed by the LEDs to the power drawn at the LM2707 input ( forward voltage characteristics of the LEDs used for the efficiency curve data 5mA 3.1V 10mA 3.3V ...
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... Block Diagram FIGURE 1. LM2707 Block Diagram 9 20099227 www.national.com ...
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... Similar interrupts in switching are trig- gered by an over-voltage protection circuit on the output and an under-voltage lockout circuit on the input. An external shutdown signal can also be applied to place the LM2707 in a low-power shutdown mode. ). The X FIGURE 3 ...
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... ON/OFF signal for the power transistor, as described in the previous section. CURRENT LIMIT The LM2707 current limit circuit senses the current through the inductor and interrupts switching when the current limit threshold is exceeded. The current limit circuit is shown in Figure 4. ...
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Product Description Figure 5 graphs the relationship between inductor current and current limit. Figure 6 plots ideal inductor current wave- forms to illustrate inductor current behavior. Figure 7 gives peak inductor current versus input voltage and shows the two regions ...
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... For high efficiency and good circuit performance, a fast schottky rectifier diode with a low forward voltage is recom- mended for use with the LM2707. The average current rating of the diode should be higher than the peak inductor current of the application. The reverse breakdown voltage of the diode should be greater than the maximum output voltage of the circuit ...
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... LM2707 circuit. www.national.com FIGURE 9. Example LM2707 LED Driver Board Layout Application Information LED DRIVE EFFICIENCY The LM2707 can be used to build a high efficiency LED drive capacitor. A circuit. The low ON resistance of the NFET power device and X the sub-bandgap feedback voltage minimize the power con- sumption of the LED-drive circuit ...
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... With the addition of an external resistor, an analog voltage can be used to adjust LED brightness, as shown in Figure 10. When the analog voltage is above the feedback voltage, 0.515V (typ.), the analog voltage source adds current to FIGURE 10. LM2707 LED-Drive Circuit with Analog Voltage Brightness Control (Continued 20 30% 3 ...
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... Application Information FIGURE 11. LM2707 LED-Drive Circuit with 2-Bit Digital Logic Brightness Control Application Circuits LM2707 DRIVING 6 LEDs www.national.com (Continued) 16 20099236 20099237 ...
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... Application Circuits (Continued) LM2707 DRIVING 3 LEDs LM2707 DRIVING 2 LEDs 20099238 20099239 17 www.national.com ...
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... Application Circuits LM2707 DC-DC VOLTAGE CONVERTER CIRCUIT Curves for V = 12V 126kΩ, R OUT FB1 2x1µ 68pF OUT X A accomodate load currents above of 15mA. Output Voltage vs. Input Voltage Power Efficiency vs. Input Voltage www.national.com (Continued) = 10kΩ 22µH (Coilcraft DT1608C-223 MBR0520L (Vishay), C FB2 C. A 1Ω ...
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Physical Dimensions inches (millimeters) unless otherwise noted 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 ...