rt8012a Richtek Technology Corporation, rt8012a Datasheet
rt8012a
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rt8012a Summary of contents
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... Internal power switches with low on-resistance of the dual step-down regulators increase efficiency and eliminate the need for external Schottky diodes. The RT8012A can run at 100% duty cycle for low dropout operation that extends battery life in portable systems. With independent Enable and Power-Good pins easy to control the power up sequence of the two converters, which is important in some applications ...
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... PGOOD2 15 EN2 RT8012A L1 2.2uH 5, 6 LX2 R3 100k 15 FB2 22uF 200k 10uF R1 100k 1 PGOOD2 15 EN2 RT8012A L1 2.2uH 5, 6 LX2 R2 100k 15 FB2 200k C2 R2 10uF 100k 13 PGOOD1 11 EN1 L2 3.3uH 7 LX1 R6 625k 12 FB1 C4 R5 10uF 200k Down Regulators ...
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... Regulator 2. The delay time can be adjusted by different capacitance. Feedback Pin of Regulator 2. Receives the feedback voltage from a resistive divider 16 FB2 connected across the output. DS8012A-01 March 2007 Preliminary Pin Function FB1 RT8012A is equal DD , PVDD1 and PVDD2 DD will be DD exceeds 90% of regulation point). www.richtek.com 3 ...
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... RT8012A Function Block Diagram Regulator 1, 2 0.8V FB1/ FB2 0.72V 0.4V POR VDD GND EN1/ EN2 www.richtek.com 4 Preliminary ISEN Slope Compensation OSC Output EA Clamp Internal- Soft Start Control Logic EN1 EN & SHDN EN2 Shutdown OC Limit Driver OTP VREF DS8012A-01 March 2007 PVDD1/ PVDD2 ...
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... Test Conditions REF Active, not Switching 0.75V FB1 FB1 EN1, EN2 = 0 V Rising DD V Hysteresis DD Switching Frequency EN2 Rising EN2 Hysteresis C5 = 0.1uF RT8012A + 0.3V) DD − 65°C to 150°C 2kV Min Typ Max Units 2.6 -- 5.5 V 0.784 0.8 0.816 V μA 500 830 1100 μA ...
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... RT8012A Parameter Regulator 1 Switch On Resistance, High Switch On Resistance, Low Peak Current Limit Output Voltage Line Regulation Output Voltage Load Regulation Regulator 2 Switch On Resistance, High Switch On Resistance, Low Peak Current Limit Output Voltage Line Regulation Output Voltage Load Regulation Note 1. Stresses listed as the above “Absolute Maximum Ratings” may cause permanent damage to the device. These are for stress ratings ...
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... Regulator 2 Load Transient Response 1.2V 1.5A IN OUT OUT L = 2.2uH 10uF OUT OUT Time (100μs/Div) Regulator 2 Load Transient Response OUT 1.2V 200mA to 800mA IN OUT OUT L = 2.2uH 10uF OUT Time (100μs/Div) RT8012A = 5V 1.2V IN OUT = 10uF OUT 1.00 1.25 1.50 www.richtek.com 7 ...
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... RT8012A Regulator 1 Ripple 3.3V OUT L = 3.3uH 10uF OUT V OUT (10mV/Div (5V/Div) Time (1μs/Div) Regulator 1 Power On from (2V/Div) V OUT (2V/Div (500mA/Div Time (1ms/Div) Regulator 1 Power On from (2V/Div) V OUT (2V/Div) I OUT (500mA/Div Time (1ms/Div) www.richtek.com ...
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... Time (1ms/Div) Regulator 2 Load Regulation 1.230 1.228 1.226 1.224 1.222 1.220 1.218 1.216 1.214 1.212 1.210 0.00 0.25 0.50 0.75 Output Current (A) Regulator 2 Output Voltage vs. Temperature 1.24 1.23 1.22 1.21 1. 1.18 -50 - Temperature RT8012A = 1.2V 1.5A OUT OUT 1.2V IN OUT 1.00 1.25 1.50 = 1.2V OUT OUT 50 75 100 125 (°C) www.richtek.com 9 ...
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... RT8012A Switching Frequency vs. Input Voltage 1400 1350 1300 1250 1200 1150 1100 1050 V = 1.2V 300mA OUT OUT 1000 2.5 3 3.5 Input Voltage (V) Regulator 1 Inductor Peak Current vs. Input Voltage 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1 3.3V OUT 1.3 4 4.3 4.6 Input Voltage (V) Regulator 1 Current Limit vs. Temperature 1.8 1.7 1.6 1.5 1.4 1.3 1 3.3V IN OUT 1.0 -50 - Temperature www.richtek.com 10 Preliminary 4 4 ...
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... Applications Information The basic RT8012A application circuit is shown in Typical Application Circuit. External component selection is determined by the maximum load current and begins with the selection of the inductor value and operating frequency followed by C and OUT 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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... IN part. Output Voltage Programming The resistive divider allows the FB pin to sense a fraction of the output voltage as shown in Figure 3. FB RT8012A GND Figure 3. Setting the Output Voltage www.richtek.com 12 Preliminary For adjustable voltage mode, the output voltage is set by an external resistive divider according to the following ...
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... Layout Considerations Follow the PCB layout guidelines for optimal performance of RT8012A. is the maximum A = 25°C can be calculated 125°C − 25°C) / 54°C/W = 1.852W for D(MAX) . For RT8012A packages, the Figure 2.0 1.8 1.6 WQFN 16L 4x4 1.4 1.2 1.0 0.8 0.6 0.4 ...
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... RT8012A 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 www.richtek.com 14 Preliminary SEE DETAIL Note : The configuration of the Pin #1 identifier is optional, but must be located within the zone indicated ...