RT9218GS Richtek USA Inc, RT9218GS Datasheet
RT9218GS
Specifications of RT9218GS
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RT9218GS Summary of contents
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Synchronous Buck PWM DC/DC and Linear Power Controller General Description The RT9218 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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RT9218 Typical Application Circuit 1000uF x 2 1uF 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 ...
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RT9218 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 0.64V 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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RT9218 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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RT9218 V Switching CC SV OUT I OUT UGATE 12Vto 10A OUT Time (10ms/Div) Power On SV OUT I OUT UGATE Time (500us/Div) Dead Time (Rising ...
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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) Soft Start & PGOOD (1V/Div) PGOOD (500mV/Div) SV ...
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RT9218 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 ...
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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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RT9218 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 OCSET sets the over-current ...
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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 & OPS falling). R must be kept lower than 37.5kΩ for large OCSET ...
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RT9218 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 ...
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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. Apply ...
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RT9218 www.richtek.com 16 DS9218-08 March 2007 ...
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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 DS9218-08 March 2007 RT9218 www.richtek.com 17 ...
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RT9218 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 Information that is provided by Richtek Technology ...