rt8287 Richtek Technology Corporation, rt8287 Datasheet
rt8287
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rt8287 Summary of contents
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... Fault condition protection includes cycle-by-cycle current limiting and thermal shutdown. An adjustable soft-start reduces the stress on the input source at startup. The RT8287 requires a minimal number of readily available external components, providing a compact solution. Ordering Information RT8287 ...
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... SW 6 BOOT PGOOD VCC 12, 13 GND 15 (Exposed Pad) 14 AGND www.richtek.com VIN BOOT RT8287 PGOOD R3 100k VCC C C 0.1µ GND AGND 14 12, 13, 15 (Exposed Pad) Table 1. Recommended Components Selection R2 (kΩ ...
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... Function Block Diagram VIN 1. 1µA 3V 1.7V VCC PGOOD FB SS DS8287-01 August 2011 Shutdown Ramp Comparator Generator + Regulator Oscillator 500kHz + Lockout Comparator Reference + Error - Amplifier + + - V C 30pF 10µA 1pF Current Sense Amplifier Driver + R - PWM Comparator 400k RT8287 - + BOOT SW GND www.richtek.com 3 ...
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... RT8287 Absolute Maximum Ratings ----------------------------------------------------------------------------------- −0.3V to 26V Supply Input Voltage Switch Voltage, SW ----------------------------------------------------------------------------------------- −0. Boot Voltage, BOOT ----------------------------------------------------------------------------------------- (SW − 0.3V) to (SW + 6V) All Other Pins ------------------------------------------------------------------------------------------------- −0. Power Dissipation 25° WDFN-14L 4x3 ------------------------------------------------------------------------------------------------ 1.667W Package Thermal Resistance (Note 2) WDFN-14L 4x3, θ ------------------------------------------------------------------------------------------ 60°C/W JA WDFN-14L 4x3, θ ...
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... Note 4. The device is not guaranteed to function outside its operating conditions. DS8287-01 August 2011 Symbol Test Conditions Sink 4mA V V Rising UVLO IN ΔV UVLO I = 5mA 47nF 25° high-effective thermal conductivity four-layer test board of JEDEC A RT8287 Min Typ Max -- 0 3.8 4 4.2 -- 400 ...
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... RT8287 Typical Operating Characteristics Efficiency vs. Output Current 100 0.5 1 Output Current (A) Reference Voltage vs. Temperature 0.84 0.83 0.82 0.81 0.80 0.79 0.78 0.77 0.76 -50 - Temperature (°C) Switching Frequency vs. Input Voltage 550 525 500 475 450 425 400 375 350 Input Voltage (V) www.richtek.com ...
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... Temperature (°C) Load Transient Response V OUT I OUT (2A/Div 12V OUT Time (100μs/Div) Output Voltage Ripple V OUT V LX (10V/Div (2A/Div) Time (1μs/Div) RT8287 V = 12V 1.22V IN OUT 50 75 100 125 = 1.22V OUT V = 12V OUT www.richtek.com 7 ...
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... RT8287 Power On from (10V/Div) V OUT (1V/Div) V PGOOD (5V/Div (5A/Div 12V Time (5ms/Div) Power On from (5V/Div) V OUT (1V/Div) V PGOOD (5V/Div (5A/Div 12V Time (2.5ms/Div) www.richtek.com (10V/Div) V OUT (1V/Div) V PGOOD (5V/Div) (5A/Div) = 1.22V OUT OUT ...
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... Figure 4. For example output voltage is regulated from a 12V input voltage, the resistor R to set input lockout threshold larger than 8V. * capacitor from the VIN pin, as can connected between target value, a resistive voltage divider can be placed RT8287 * smaller than the can be selected EN2 www.richtek.com 9 ...
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... FB PGOOD R3 100k VCC C C GND AGND 14 12, 13, 15 (Exposed Pad BOOT VIN RT8287 EN2 PGOOD R3 100k VCC C C GND AGND 14 12, 13, 15 (Exposed Pad) Inductor Selection For a given input and output voltage, the inductor value and operating frequency determine the ripple current. The ripple current Δ ...
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... V IN OUT = This simple worst case condition is commonly and C IN OUT Capacitance ( best, this ringing can couple to the output IN large enough to damage the IN RT8287 , where I = OUT RMS Case Size 1210 1210 1206 1210 1210 1210 www.richtek.com 11 ...
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... T is the maximum junction temperature, T J(MAX) the ambient temperature, and JA thermal resistance. For recommended operating condition specifications of the RT8287, the maximum junction temperature is 125 C and T is the ambient temperature. The junction to ambient A thermal resistance layout dependent. For WDFN- JA 14L 4x3 package, the thermal resistance standard JEDEC 51-7 four-layer thermal test board ...
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... C IN VIN AGND GND SW GND 3 12 VCC GND C SS BOOT PGOOD BOOT OUT C OUT GND Figure 7. PCB Layout Guide RT8287 GND C SS Place the R2 feedback as close to the possible OUT www.richtek.com 13 ...
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... RT8287 Outline Dimension Symbol 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 ...