LM2833XSDEVAL National Semiconductor, LM2833XSDEVAL Datasheet
LM2833XSDEVAL
Specifications of LM2833XSDEVAL
Related parts for LM2833XSDEVAL
LM2833XSDEVAL Summary of contents
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... Additional features include internal soft-start cir- cuitry to reduce inrush current, cycle-by-cycle current limit, frequency foldback, thermal shutdown, and output over-volt- age protection. Typical Application Circuit © 2009 National Semiconductor Corporation Features ■ Input voltage range of 3.0V to 5.5V ■ Output voltage range of 0.6V to 4.5V ■ ...
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Connection Diagrams 10-pin LLP Ordering Information Frequency Order Number Option LM2833XMY LM2833XMYX 1.5MHz LM2833XSD LM2833XSDX LM2833ZMY LM2833ZMYX 3MHz LM2833ZSD LM2833ZSDX Pin Descriptions Pin(s) Name 1 VINC SGND PGND ...
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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. VINC, VIND FB Voltage EN Voltage SW Voltage ESD Susceptibility (Note 4) Electrical Characteristics type are for T = 25°C only; limits in boldface type apply over the junction temperature (T J and Maximum limits are guaranteed through test, design, or statistical correlation ...
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Symbol Parameter Junction to Ambient θ LFPM Air Flow (Note 3) θ Junction to Case (Note Thermal Shutdown Threshold SD T Thermal Shutdown Hysteresis SD_HYS Note 1: Absolute Maximum Ratings indicate limits beyond which damage ...
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Typical Performance Characteristics Unless otherwise specified and T IN Efficiency vs Load Current - "LM2833X" and "LM2833Z" Efficiency vs Load Current - "LM2833Z" Oscillator Frequency vs Temperature - "LM2833Z" = 25°C. A Efficiency vs Load Current - ...
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R vs Temperature (LLP-10 Package) DS(ON) LM2833X I (Quiescent Current Temperature FB www.national.com R vs Temperature (eMSOP-10 Package) DS(ON) 30013229 LM2833Z I 30013231 Frequency Foldback 30013233 6 30013230 (Quiescent Current) Q 30013232 30013228 ...
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Loop Gain and Phase - "LM2833X" 30013235 Load Step Response - "LM2833X" 30013247 Startup "LM2833X" 30013252 Loop Gain and Phase - "LM2833Z" Line Transient Response - "LM2833X" Shutdown "LM2833X" 7 30013236 30013248 30013253 www.national.com ...
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Startup with EN tied to V Short-circuit Release - "LM2833X" www.national.com - "LM2833X" IN 30013254 Recovery from Thermal Shutdown - "LM2833X" 30013251 8 Short-circuit Triggering - "LM2833X" 30013250 30013240 ...
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Block Diagram FIGURE 1. Simplified Block Diagram 9 30013269 www.national.com ...
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Application Information THEORY OF OPERATION The LM2833 is a constant frequency PWM buck regulator IC that delivers a 3.0A load current. The regulator is available in preset switching frequencies of 1.5MHz or 3.0MHz. This high frequency allows the LM2833 to ...
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FIGURE 3. Startup Response to V FIGURE 4. Startup Response to V FIGURE 5. Startup Response to V with 100µs rise time IN FREQUENCY FOLDBACK The LM2833 uses frequency foldback to help limit switch cur- rent and power dissipation during ...
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FIGURE 6. Adding a C FIGURE 7. Loop Gain and Phase without C FIGURE 8. Loop Gain and Phase with C www.national.com 30013255 Capacitor FF 30013237 FF OUTPUT OVER-VOLTAGE PROTECTION The LM2833 has a built in output over-voltage comparator that ...
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THERMAL SHUTDOWN Thermal shutdown limits total power dissipation by turning off the internal power switch when the IC junction temperature typically exceeds 165°C. After thermal shutdown occurs, the power switch does not turn on again until the junction tem- perature ...
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In cases where large capacitance is required, use surface mount ca- pacitors such as Tantalum capacitors and place at least a 4.7µF ceramic capacitor close to the V recommended to use X7R ...
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If the inductor ripple current is fairly small, the conduction losses can be simplified to COND OUT DS(ON) Switching losses are also associated with the internal power switch. They occur during the switch on ...
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LM2833X Design Example 1 FIGURE 11. LM2833X (1.5MHz): V Part ID U1 C1, Input Cap C2, Output Cap C3, Bypass Cap D1, Catch Diode Schottky, 0.33V at 3A www.national.com = 3.3V, Output = 1.2V/3.0A IN ...
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LM2833X Design Example 2 FIGURE 12. LM2833X (1.5MHz): V Part ID U1 3.0A Buck Regulator C1, Input Cap C2, Output Cap C3, Bypass Cap 0.22µF, 10V, X7R C , Feed-forward Cap FF D1, Catch Diode Schottky, 0.43V at 3A, V ...
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LM2833Z Design Example 3 FIGURE 13. LM2833Z (3MHz): V Part ID U1 C1, Input Cap C2, Output Cap C3, Bypass Cap D1, Catch Diode Schottky, 0.33V at 3A www.national.com = 3.3V, Output = 1.2V/3.0A IN ...
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LM2833Z Design Example 4 FIGURE 14. LM2833Z (3MHz): V Part ID U1 3.0A Buck Regulator C1, Input Cap C2, Output Cap C3, Bypass Cap 0.22µF, 10V, X7R C , Feed-forward Cap FF D1, Catch Diode Schottky, 0.43V at 3A, V ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 10-Lead eMSOP Package NS Package Number MUC10A 10-Lead LLP Package NS Package Number SDA10A 20 ...
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Notes 21 www.national.com ...
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