RT8259 RICHTEK [Richtek Technology Corporation], RT8259 Datasheet
RT8259
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RT8259 Summary of contents
Page 1
... Step-Down Converter General Description The RT8259 is a high voltage buck converter that can support the input voltage range from 4.5V to 24V and the output current can 1.2A. Current Mode operation provides fast transient response and eases loop stabilization. The chip also provides protection functions such as cycle- by-cycle current limiting and thermal shutdown protection ...
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... RT8259 Table 1. Recommended Component Selection 22μ μ μ μ μ (V) 1.2 1.8 2.5 OUT L1 (μ 3.6 R1 (kΩ (kΩ) 124 49.9 29.4 Functional Pin Description Pin No. Pin Name Bootstrap. A capacitor is connected between PHASE and BOOT pins to form a floating 1 BOOT supply across the power switch driver. This capacitor is needed to drive the power switch‘s gate above the supply voltage ...
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... Symbol Test Conditions 4.5V ≤ V ≤ 24V 0. DS(ON 0V PHASE − 4.8V LIM BOOT PHASE Rising RT8259 + 0.3V PHASE Min Typ Max Unit 0.784 0.8 0.816 V μA -- 0.1 0.3 Ω -- 0.3 -- μ 1.6 2 1.2 1.4 1.6 MHz -- 100 -- ns 3 ...
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... RT8259 Parameter Shutdown Current Quiescent Current Thermal Shutdown Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2. θ ...
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... Load Current (A) Output Voltage vs. Temperature 3.38 3.36 3.34 3.32 3.30 3.28 3.26 3.24 3.22 -50 - Temperature (°C) Frequency vs. Temperature 1.55 1.50 1.45 1.40 1.35 1.30 1.25 1. 12V OUT 1.15 -50 - Temperature (°C) RT8259 V = 12V 24V 3.3V OUT 1 1.1 1 24V 12V OUT 75 100 125 = 3.3V 0.3A OUT 75 100 125 www.richtek.com 5 ...
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... RT8259 Quiescent Current vs. Input Voltage 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 4 6.5 9 11.5 Input Voltage (V) Load Transient Response V = 12V 3.3V OUT V OUT (50mV/Div) I OUT (500mA/Div) Time (50μs/Div) Switching V OUT (5mV/Div) V PHASE (10V/Div (1A/Div 12V Time (250ns/Div) www.richtek.com 2V 16 0.6A to 1.2A OUT (50mV/Div) (500mA/Div) ...
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... Power On from 12V (5V/Div) V OUT (1V/Div (500mA/Div) Time (250μs/Div) DS8259-03 March 2011 = 3.3V 1.2A OUT OUT V (5V/Div) V OUT (1V/Div (500mA/Div) Power Off from 12V OUT EN Time (100μs/Div) RT8259 = 3.3V 1.2A OUT www.richtek.com 7 ...
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... RT8259 Application Information The RT8259 is a high voltage buck converter that can support the input voltage range from 4.5V to 24V and the output current can 1.2A. Output Voltage Setting The resistive voltage divider allows the FB pin to sense a fraction of the output voltage as shown in Figure 1. ...
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... At best, this ringing can couple to the output and be large enough to damage the part. IN immediately shifts by an amount OUT (ESR) also begins to charge or discharge LOAD generating a feedback error signal for the regulator to to its steady-state value. During this recovery OUT can be monitored for overshoot or ringing that OUT RT8259 www.richtek.com 9 ...
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... P D(MAX) T/SOT-23-6 packages The maximum power dissipation depends on operating ambient temperature for fixed T J(MAX) θ . For RT8259 packages, the Figure 3 of derating curves JA allows the designer to see the effect of rising ambient temperature on the maximum power allowed. 0.50 0.45 0.40 0.35 ...
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... Capacitance ( ( OUT Current Rating (A) Dimensions (mm 4.7 45 1.87 18 5.7 Case Size 1206 1206 1206 1206 1206 1206 Package DO-214AC DO-214AC DO-214AC DO-214AB RT8259 4 2 3.8 www.richtek.com 11 ...
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... RT8259 Outline Dimension Symbol www.richtek.com Dimensions In Millimeters Min Max 0.889 1.295 0.000 0.152 1.397 1.803 0.250 0.560 2.591 2.997 2.692 3.099 0.838 1.041 0.080 0.254 0.300 0.610 SOT-23-6 Surface Mount Package H L Dimensions In Inches ...
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... TSOT-23-6 Surface Mount Package Richtek Technology Corporation Taipei Office (Marketing) 5F, No. 95, Minchiuan Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)86672399 Fax: (8862)86672377 Email: marketing@richtek.com RT8259 H L Dimensions In Inches Min Max 0.028 0.039 0.000 0.004 0.055 0.071 ...