RT8251GSP Richtek USA Inc, RT8251GSP Datasheet
RT8251GSP
Specifications of RT8251GSP
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RT8251GSP Summary of contents
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Step-Down Converter General Description The RT8251 is a monolithic step-down switch mode converter with a built-in internal power MOSFET. It achieves 5A continuous output current over a wide input supply range with excellent load and line regulation. ...
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... RT8251 GND COMP ( 2.2 RT8251GSP : Product Number RT8251 YMDNN : Date Code GSPYMDNN C L BOOT 4.7µH 100nF D R1 B540C 30.9k C 22µ 2.2nF 22k 10k C P (Open) C BOOT L 100nF 4.7µ B540C 30.9k C OUT 22µ 2.2nF 22k ...
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Functional Pin Description Pin No. SOP-8 WQFN-16L 3x3 (Exposed Pad 15 (Exposed Pad) 9 (Exposed Pad 10, 11, 12, 13 ...
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RT8251 Function Block Diagram VIN V CC Internal Regulator 1µ 10k - EN + 1.1V Shutdown 3V Comparator V CC 10µA SS Absolute Maximum Ratings Supply Voltage, V --------------------------------------------------------------------------------------- 0.3V to 26V l IN Switching Voltage, V ----------------------------------------------------------------------------------- ...
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Electrical Characteristics (V = 12V unless otherwise specified Parameter Feedback Reference Voltage High-Side Switch-On Resistance Low-Side Switch-On Resistance High-Side Switch Leakage Current Limit Current Sense Transconductance Error Amplifier Tansconductance Oscillator Frequency Short Circuit Oscillation ...
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RT8251 Typical Operating Characteristics Efficiency vs. Load Current 100 0.5 1 1.5 2 Load Current (A) Output Voltag Deviation vs. Load Current 24V IN 1.5 V ...
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Switching Frequency vs. Input Voltage 610 600 590 580 570 560 550 4 6.5 9 11.5 Input Voltage (V) Current Limit vs. Duty Cycle 9.3 8.7 8.1 7.5 6.9 6.3 5 Duty Cycle (%) Load ...
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RT8251 Power On from (5V/Div) V OUT (2V/Div) Time (250μs/Div) www.richtek.com (5V/Div) V OUT (2V/Div 12V 3.3V OUT OUT Power On from 12V, ...
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Application Information The RT8251 is an asynchronous high voltage buck converter that can support the input voltage range from 4.75V to 24V and the output current can 5A. Output Voltage Setting The resistive divider allows the FB ...
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RT8251 Table 2. Suggested Inductors for Typical Application Circuit Component Series Supplier TDK SLF10165 TAIYO YUDEN NR10050 TDK VLF12060 Diode Selection When the power switch turns off, the path for the current is through the diode connected between the switch ...
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V can be monitored for overshoot or OUT ringing that would indicate a stability problem. EMI Consideration Since parasitic inductance and capacitance effects in PCB circuitry would cause a spike voltage on the SW pin when high-side MOSFET ...
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RT8251 SOP-8 (Exposed Pad) pad (Figure 6a), Adding copper area of pad under the SOP-8 (Exposed Pad) (Figure 6.b) reduces the JA increasing the copper area of pad to 70mm reduces the to 49 C/W. JA The maximum power dissipation ...
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Layout Consideration Follow the PCB layout guidelines for optimal performance of the RT8251. Keep the traces of the main current paths as short and } wide as possible. Put the input capacitor as close as possible to the device } ...
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RT8251 GND Input capacitor must be placed as close to the IC as possible Table 3. Suggested Capacitors for C Location Component Supplier MURATA C IN TDK C IN TAIYO YUDEN C IN MURATA C OUT MURATA C ...
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Outline Dimension Symbol DS8251-01 March 2011 SEE DETAIL Note : The configuration of the Pin #1 identifier is ...
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RT8251 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 ...