RT8279 RICHTEK [Richtek Technology Corporation], RT8279 Datasheet
RT8279
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RT8279 Summary of contents
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... Step-Down Converter General Description The RT8279 is a step-down regulator with an internal power MOSFET. It achieves 5A of continuous output current over a wide input supply range with excellent load and line regulation. Current mode operation provides fast transient response and eases loop stabilization. ...
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... GND 9 (Exposed Pad) 7 VIN 8 SW www.richtek.com VIN BOOT C IN 4.7µF/ RT8279 8 50V GND FB Table 1. Recommended Component Selection R2 (kΩ) 100 100 100 58.6 100 31.6 100 18 High Side Gate Drive Boost Input. BOOT supplies the drive for the high side N-MOSFET switch ...
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... Function Block Diagram VIN Regulator EN Reference FB 12k DS8279-01 December 2011 Current Sense Ramp Generator Oscillator S 500kHz + R - Error PWM Amplifier + Comparator - 30pF 400k 13pF Amplifier - + BOOT Q Driver SW Bootstrap Control GND RT8279 www.richtek.com 3 ...
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... RT8279 Absolute Maximum Ratings ------------------------------------------------------------------------------------------ −0.3V to 40V Supply Voltage Switching Voltage, SW ------------------------------------------------------------------------------------- −0. BOOT Voltage ------------------------------------------------------------------------------------------------- (V The Other Pins ------------------------------------------------------------------------------------------------ −0. Power Dissipation 25° SOP-8 (Exposed Pad) -------------------------------------------------------------------------------------- 1.333W Package Thermal Resistance (Note 2) SOP-8 (Exposed Pad), θ --------------------------------------------------------------------------------- 75°C/W JA SOP-8 (Exposed Pad), θ ...
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... JEDEC 51-7. θ is measured measured at the exposed pad of the package. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. DS8279-01 December 2011 RT8279 is JC www.richtek.com 5 ...
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... RT8279 Typical Operating Characteristics Efficiency vs. Output Current 100 12V 32V 36V Output Current (A) Reference Voltage vs. Temperature 1.230 1.228 1.226 1.224 1.222 1.220 1.218 1.216 1.214 1.212 1.210 -50 - Temperature (°C) Frequency vs. Input Voltage ...
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... Input Voltage (V) Load Transient Response OUT I OUT (2A/Div 12V OUT Time (100μs/Div) Switching V OUT (5A/Div 12V Time (1μs/Div) RT8279 5V 0. OUT = 5V OUT OUT www.richtek.com 7 ...
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... RT8279 Power On from (5V/Div) V OUT (5V/Div (5A/Div 12V Time (2.5ms/Div) www.richtek.com (5V/Div) V OUT (5V/Div (5A/Div OUT OUT Power Off from 12V 5V OUT OUT Time (2.5ms/Div) DS8279-01 December 2011 ...
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... The EN pin is the chip enable input. Pull the EN pin low (<0.4V) will shutdown the device. During shutdown mode, V OUT the RT8279 quiescent current drops to lower than 25μA. Drive the EN pin to high (>1.4V, <5.5V) will turn on the R1 device again. If the EN pin is open, it will be pulled to high by internal circuit ...
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... RT8279 Table 2. Suggested Inductors for Typical Application Circuit Component Series Supplier TAIYO NR10050 YUDEN SLF12565 TDK Diode Selection When the power switch turns off, the path for the current is through the diode connected between the switch output and ground. This forward biased diode must have a minimum voltage drop and recovery times ...
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... A the junction to ambient thermal resistance. For recommended operating conditions specification of RT8279, the maximum junction temperature is 125°C. The junction to ambient thermal resistance dependent. For PSOP-8 package, the thermal resistance θ is 75°C/W on the standard JEDEC 51-7 four-layers JA thermal test board ...
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... RT8279 The maximum power dissipation depends on operating ambient temperature for fixed T resistance θ . For the RT8279, the Figure curves allows the designer to see the effect of rising ambient temperature on the maximum power dissipation allowed. 2.2 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 Ambient Temperature (°C) Figure 5. Derating Curves for RT8279 Package (a) Copper Area = (2 ...
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... GRM31CR60J476M C3225X5R0J476M GRM32ER71C226M C3225X5R1C22M V (V) I (A) RRM OUT OUT C OUT C OUT VIN C IN GND Input capacitor should be placed as close to the IC as possible. Capacitance (μF) Case Size 4.7 1206 4.7 1206 47 1206 47 1210 22 1210 22 1210 Package SMC SMC RT8279 www.richtek.com 13 ...
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... RT8279 Outline Dimension EXPOSED THERMAL PAD (Bottom of Package) Symbol Option 1 Option 2 Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Information that is provided by Richtek Technology Corporation is believed to be accurate and reliable. Richtek reserves the right to make any change in circuit design, specification or other related things if necessary without notice at any time ...