RT9218BGS RICHTEK [Richtek Technology Corporation], RT9218BGS Datasheet
RT9218BGS
Related parts for RT9218BGS
RT9218BGS Summary of contents
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Synchronous Buck PWM DC-DC and Linear Power Controller General Description The RT9218B is a dual output with one synchronous buck PWM and one linear controller. The part is proposed to generate logic-supply voltages for PC based systems. The high-performance ...
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RT9218B Typical Application Circuit 1uF x 2 1000uF 2.2uH 1000uF × OUT REF = × OUT REF V ...
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Functional Pin Description UGATE (Pin 2) Upper gate driver output. Connect to gate of the high-side power N-MOSFET. This pin is monitored by the adaptive shoot-through protection circuitry to determine when the upper MOSFET has turned off. BOOT (Pin 1) ...
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RT9218B Function Block Diagram Bias & Regulators (3V_Logic & 3VDD_Analog) VCC + DRV - FBL PGOOD FB Timing Diagram FSB_VTT (1.2V @ 5Amp) VTT_GD www.richtek.com 4 VCC Power On Reference Reset 0.8V REF 0.6V UV_S + Soft-Start - & Fault ...
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Absolute Maximum Ratings Supply Voltage, V -------------------------------------------------------------------------------------- 16V CC BOOT ------------------------------------------------------------------------------------ 16V BOOT PHASE PHASE to GND DC ------------------------------------------------------------------------------------------------------------- −5V to 15V < 200ns ------------------------------------------------------------------------------------------------------ −10V to 30V BOOT to PHASE ------------------------------------------------------------------------------------------ 15V BOOT to GND DC ...
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RT9218B Parameter Error Amplifier (GM) E/A Transconductance Open Loop DC Gain Linear Regulator DRV Driver Source Reference Voltage PWM Controller Gate Drivers (V Upper Gate Source Upper Gate Sink Lower Gate Source Lower Gate Sink Dead Time Protection FB Under-Voltage ...
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Typical Operating Characteristics (V = 2.5V, unless otherwise specified ) OUT Efficiency vs. Output Current 1 0.95 0.9 0.85 0.8 0.75 0.7 0. 12V 0 Output Current (A) Reference Voltage ...
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RT9218B Transient Response (Rising) UGATE (10V/Div) SV OUT (100mV/Div 12V 15A OUT I L (10A/Div 1/20ms 2.5A/us Time (5us/Div) Power On SV OUT I OUT UGATE ...
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Application Information Inductor Selection The selection of output inductor is based on the considerations of efficiency, output power and operating frequency. Low inductance value has smaller size, but results in low efficiency, large ripple current and high output ripple voltage. ...
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RT9218B The AC impedance of output capacitor at operating frequency is quite smaller than the load impedance, so the ripple current (Δ the inductor current flows mainly L through output capacitor. The output ripple voltage is described as ...
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OPS (Over Current Setting, VIN_POR and Shutdown) 1.OCP Sense the low-side MOSFET's R Connecting a resistor (R ) from this pin to the source of the upper MOSFET and the drain of the lower MOSFET sets OCSET the over-current trip ...
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RT9218B 2. VIN_POR UGATE will continuously generate a 10kHz colck with 1% duty cycle before V is ready detecting V crossing 1.5V four times (rising & falling). OPS R must be kept lower than 37.5kΩ for large R ...
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Under Voltage Protection The voltage at FB and FBL pin is monitored and protected against UV (under voltage). The UV threshold is the FB or FBL under 75%. UV detection has 30μs triggered delay. When OC or UV_FBL is trigged, ...
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RT9218B Figure 10 shows the connections of the critical components in the converter. Note that the capacitors C of them represents numerous physical capacitors. Use a dedicated grounding plane and use vias to ground all critical components to this layer. ...
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DS9218B-09 March 2007 RT9218B www.richtek.com 15 ...
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RT9218B According to our test experience, you must still notice two items to avoid noise coupling : 1.The ground plane should not be separated. 2.V rail adding the LC filter is recommended. CC www.richtek.com 16 DS9218B-09 March 2007 ...
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Outline Dimension J I Symbol Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 DS9218B-09 March 2007 ...