RT8203GA Richtek USA Inc, RT8203GA Datasheet
RT8203GA
Specifications of RT8203GA
Related parts for RT8203GA
RT8203GA Summary of contents
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High-Efficiency, Quad Output, Main Power-Supply Controllers for Notebook Computers General Description The RT8203 dual step-down, Switch Mode Power Supply (SMPS) controllers generate logic-supply voltages in battery-powered systems. The RT8203 include two pulse- width modulation (PWM) controllers, adjustable from 2V to ...
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RT8203 Typical Application Circuit 5V ALWAYS ON C1 4.7µF C2 1µ 1µF C6 10µF AO4702 V OUT5 L1 5V C10 D3 TON = VCC f = 200kHz L1 = 7.6μH C10 = 330μF www.richtek.com ...
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ALWAYS ON C1 4.7µF C2 1µ 1µF C6 10µF AO4702 V OUT5 L1 5V C10 D3 R7 15k C13 0.1µF R8 10k C12 0.22µF TON = VCC f = 200kHz L1 = 7.6μH C10 = 330μF ...
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RT8203 Functional Pin Description Pin No. Pin Name 1 NC Connect to GND. Power Good Open Drain Output. PGOOD is pulled low if either output is disable PGOOD more than 8.75% below its normal value. VOUT3 Enable ...
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Pin No. Pin Name Inductor Connection for 5V SMPS. PHASE5 is the internal lower supply rail for the 15 PHASE5 UGATE5 high side gate driver, and the current sense input for the 5V SMPS. High Side N-MOSFET Floating Gate-Driver Output ...
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RT8203 Function Block Diagram BOOT3 UGATE3 PHASE3 LGATE3 ILIM3 FB3 VOUT3 LDO3 ON3 ON5 EN PRO VIN VOUTx On-time Compute VREF SS (internal) FBx 1.1xV PRO 0.7xV 0.9xV REF PGOOD www.richtek.com 6 VIN U3 Driver VOUT3 L3 PWM Driver Controller ...
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Absolute Maximum Ratings , EN to GND ------------------------------------------------------------------------------ −0.3V to 25V Input Voltage BOOTx to GND ------------------------------------------------------------------------------------------------- −0.3V to 30V PHASEx to BOOTx -------------------------------------------------------------------------------------------- −6V to 0.3V PHASEx to GND ------------------------------------------------------------------------------------------------ −1V to 25V VCC, LDOx, VOUTx, ONx, ...
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RT8203 Parameter Symbol ΔV DC Load Regulation ΔV Line Regulation Current-Limit Threshold (Positive, Default) Current-Limit Threshold (Positive, Adjustable) Zero-Current Threshold Soft-Start Ramp Time Operating Frequency f OSC On-Time Pulse Width Minimum Off-time t OFF Maximum Duty Cycle Internal Regulator And ...
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Parameter Symbol LDO3 Bootstrap Switch Resistance VREF Output Voltage V REF VREF Load Regulation VREF Sink Current VIN Standby Supply I Standby Current VIN Shutdown Supply I SD Current Quiescent Power Consumption Fault Detection Over Voltage Trip Threshold Over Voltage ...
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RT8203 Parameter Symbol Input Leakage Current EN Input Trip level UGATEx Driver Sink/Source Current LGATEx Driver Source Current LGATEx Driver Sink Current UGATEx Driver On-Resistance LGATEx Driver On-Resistance VOUTx Discharge-Mode On-Resistance Note 1. Stresses listed as the above “Absolute Maximum ...
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Typical Operating Characteristics No load on LDO5, LDO3,VOUT5, VOUT3 and REF, T VOUT5 Efficiency vs. Load Current 100 Ultrasonic Mode 50 Forced CCM Mode 0.001 0.01 Load Current (A) VOUT5 Efficiency ...
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RT8203 VOUT5 Switching Frequency vs. Load Current 250 225 Forced CCM Mode 200 175 150 125 100 75 50 Ultrasonic Mode 25 0 0.001 0.01 Load Current (A) VOUT5 Switching Frequency vs. Load Current 250 225 Forced CCM Mode 200 ...
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LDO5 Output Voltage vs. Output Current 5.10 5.05 5.00 4.95 4. 12V, IN ON3 = ON5 = GND 4. Output Current (mA) V vs. Output Current REF 2.005 2.003 2.001 1.999 1.997 1.995 ...
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RT8203 Power (10V/Div) LDO5 (2V/Div) LDO3 (2V/Div) REF (2V/Div) Time (400 Delayed Start ON3 (5V/Div) VOUT5 (2V/Div) VOUT3 (2V/Div) Time (400 VOUT5 Load Transient Response V = 12V, SKIP = VCC(Forced CCM Mode OUT_ac-coupled (100mV/Div) ...
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VOUT5 OVP SKIP = GND(Diode-Emulation Mode) VOUT5 (5V/Div) LGATE5 (5V/Div) VOUT3 (2V/Div) LGATE3 (10V/Div) V Time (2ms/Div) VOUT5 Shorted Start Up VOUT5 Shorted, SKIP = VCC(Forced CCM Mode) VOUT5 (2V/Div) Inductor Current (5A/Div) UGATE5 (20V/Div) LGATE5 (5V/Div 12V, ...
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RT8203 Application Information The RT8203 is a dual, Mach Response valley mode synchronous buck controller. The controller is designed for low voltage power supplies for notebook computers. Richtek's Mach Response specifically designed for providing 100ns “instant-on” response to load steps ...
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Diode-Emulation Mode ( SKIP = GND) In Diode-Emulation mode, RT8203 automatically reduces switching frequency at light load conditions to maintain high efficiency. This reduction of frequency is achieved smoothly and without increase of V regulation. As the output current decreases ...
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RT8203 load; use an additional 1μF per 5mA of internal and external load. When the 5V main output voltage is above the LDO5 switchover threshold, an internal 1.4Ω N-MOSFET switch connects VOUT5 to LDO5 while simultaneously shutting down the LDO5 ...
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Soft-Start A build-in soft-start is used to prevent surge current from power supply input after ONx is enabled. It clamps the ramping of internal reference voltage which is compared with the FBx signal. The typical soft-start duration is 1.5ms period. ...
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RT8203 Power-Up Sequencing and On/Off Controls (ONx) ON3 and ON5 control SMPS power-up sequencing. When RT8203 applies in the single channel mode, ON3 or ON5 enables the respective outputs when ONx voltage rising above 2.4V, and disables the respective outputs ...
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In non-CPU applications, the output capacitor's size depends on how much ESR is needed to maintain an acceptable level of output voltage ripple : V ≤ P-P ESR × LIR I LOAD(MAX) where V is the peak-to-peak output voltage ripple. ...
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RT8203 VOUT K-Factor (μs) VCC 4.90 GND 2.45 Mode Condition Power-UP LDOx < UVLO threshold RUN EN = High, ON3 or ON5 enabled Over Voltage Either output > 111% of nominal Protection level, PRO = Low Either ...
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EN (V) VON5 (V) Low X “ >2.4V ” Low => High “ >2.4V ” Low => High “ >2.4V ” Low => High “ >2.4V ” VREF => High “ >2.4V ” VREF => High “ >2.4V ” VREF ...
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RT8203 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 Information that is provided by Richtek Technology Corporation ...