rt9238 ETC-unknow, rt9238 Datasheet

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... VRM8.5 PWM and Triple Linear Power System Controller General Description The RT9238 is a 4-in-one power controller optimized for high-performance microprocessor and computer applications. The IC integrates a PWM controller, triple linear controller as well as monitoring and protection functions into a 28-pin SOP package. The PWM controller regulates the microprocessor core voltage with a synchronous buck converter. The first linear controller supplies the computer system’ ...

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... C14 Z1 1µF 15V C2 28 1000pF VCC OCSET1 FIX FIX 1K 8 PGOOD 27 UGATE1 1 26 PHASE1 DRIVE2 11 VSEN2 25 LGATE1 RT9238 C6 24 1µF PGND 22 9 FB1 VTTPG 16 21 VAUX VDAC + C15 R6 20 10µF ICOMP 1K 7 VID25 VID25 18 DRIVE3 6 VID0 VID0 5 ...

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... VSEN3 4 VID2 VID2 3 VID3 VID3 10 FAULT/VID4 15 DRIVE4 12 SS24 14 13 VSEN4 SS13 GND C12 0.1µF 17 Fig.2 VRM 8.4 & 8.5 Power Solution RT9238 PGOOD Q1 R3 PHB83N03LT 10K VCORE VRM8.5 L2; 1.8µ 1µF 8000µF PHB95N03LT C17 1µF C16 10nF R13; 47K VAUX R15 ...

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... RT9238 Function Block Diagram + + + + + + www.richtek-ic.com.tw 4 Preliminary + + + + + + + + DS9238-01 July 2001 ...

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... DRIVE3, and DRIVE4 Open V = 4.5V OCSET1 V = 4.5V OCSET1 V = 4.5V OCSET1 V = 4.5V OCSET1 VDAC + 40mV ∆ V OSC RT9238 +15V GND−0. +0.3V CC GND−0. 0°C ~ +70°C 0°C ~ +125°C −65°C ~ +150°C 300°C 60°C/W +12V±10% 0°C to 70°C 0°C to 125°C Min Typ ...

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... RT9238 Parameter Linear Regulators ( OUT2 OUT3 VSEN3,4 Voltage Regulation VSEN2 Regulation Voltage VSEN3 Regulation Voltage VSEN3 Bias Current VSEN4 Regulation Voltage VSEN4 Bias Current Under-Voltage Level (All Linears) (VSEN/VREG) Under-Voltage Hysteresis (All Linears) (VSEN/VREG) Output Drive Current (All Linears) Synchronous PWM Controller Error Amplifier ...

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... T = 25°C A 0.6 0.2 -0.2 -0 300 V = 12V CC 275 250 225 200 175 150 60 80 100 120 (°C) RT9238 I vs. V OCSET1 (Volt Line Regulation OUT2,3 (Volt vs. Temperature OCSET1 V -40 - ...

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... RT9238 V vs. Temperature OUT1 1 0.6 0.2 -0.2 -0.6 -1 -40 - Temperature Dead Time LGATE1 2 > 2 > 1 > 1 > 2 > 2 > 1 > 1 > Volt Volt Time V Short OUT2,3 > 1 > 1 > 1 > > 2 > 2 > 2 > ...

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... This pin is monitored for under-voltage events. DRIVE4 (Pin 15) Connect this pin to the gate of an external MOSEFT. This pin provides the drive for the 1.8V regulator’s pass transistor. regulator output RT9238 pulled high, the DACOUT regulator. Pulling this pin below 0.8V induces ) and the AGP OUT1 ) ...

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... RT9238 VAUX (Pin 16) This pin provides boost current for the three linear regulator output drives in the event bipolar NPN transistors (instead of N-channel MOSFETs) are employed as pass elements. The voltage at this pin is monitored for power-on reset (POR) purpose. GND (Pin 17) Signal ground for the IC. All voltage levels are measured with respect to this pin ...

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... Functional Description Operation The RT9238 monitors and precisely controls 4 output voltage levels (Refer to Figures 1, 2, and function block designed for microprocessor computer applications with 3.3V, 5V, and 12V bias input from an ATX power supply. The IC has one PWM and three linear controllers. The PWM controller is ...

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... RT9238 ATX12V 10V VTTPG SS13 ATX5V SS24 PGOOD 0V 3.0V ATX3.3V V (1.8V) OUT4 V (1.5V) OUT3 T4T5 TIME Fig.3 Soft-start Interval Fault Protection All four outputs are monitored and protected against extreme overload. The chip’s response to an output overload is selective, depending on the faulting output ...

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... The maximum R temperature 2. The minimum I 3. Determine I where ∆I is the output inductor ripple current. For an equation for the ripple current see the section under component guidelines titled ‘Output Inductor Selection’. RT9238 respective C capacitors are SS ) programs the over- OCSET (V ) that is ...

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... RT9238 OVER-CURRENT TRIP: V > SET > I × R ×R iD DS(ON) OCSET OCSET R OCSET OCSET I V OCSET 200µA VCC UGATE DRIVE _ OC PHASE GATE PWM V CONTROL PHASE V OCSET Fig.6 Current Limiting Setting OUT1 Voltage Program The output voltage of the PWM converter is programmed to discrete levels between 1.090V and ...

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... Programming a the ATX 3.3V output. Layout Considerations MOSFETs switch very fast and efficiently. The speed with which the current transitions from one device to another interconnecting impedances and parasitic circuit RT9238 Normal OUT1 Voltage DACOUT VID25 1.525+40mV=1.565 1 1.550+40mV=1.590 0 1 ...

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... There are two sets of critical components in a DC-DC converter using an RT9238 controller. The switching power components are the most critical because they switch large amounts of energy, and as such, they tend to generate equally large amounts of noise. The ...

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... Error Amp COMP VNI Isense REF _ RT9238 V Maximum CORE V Typical CORE V Minimum CORE Fig.11 V Load Line CORE CORE A RT9238 internal trans- . inductor current IL. In DS- IL/3k. DS(ON) SENSE = SENSE V5V IM1 UG IL PHASE IM2 Rds- DAC Buffer ...

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... RT9238 Fig.13, 14 shown the I and VCORE wave SENSE forms. 0µA -20µA -40µA -60µA -80µA 1.6ms 1.8ms Time Time Fig.13 I Current SENSE 1.4V 1.3V 1.2V 1.6ms 1.8ms Time Time Fig.14 V Wave Form at Load Transient CORE Component Selection Guidelines Output Capacitor Selection The output capacitors for each output have unique requirements ...

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... MOSFET Selection/Considerations L I × O TRAN = The RT9238 requires 5 external transistors. Two N- V OUT channel MOSFETs are employed by the PWM converter. The GTL, AGP, and memory linear RISE controllers can each drive a MOSFET or a NPN bipolar as a pass transistor. All these transistors ...

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... MOSFET’s body diode or the output capacitances associated with either MOSFET. The gate charge losses are dissipated by the controller IC (RT9238) and do not contribute to the MOSFETs’ heat rise. Ensure that both MOSFETs are within their maximum junction temperature at high ambient ...

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... OUT4, a NPN transistor is recommended for use as a pass element on this output (Q5). An low gate threshold NMOS could be used, but meeting the requirements would then depend on the VCC bias being sufficiently high to allow control of the MOSFET. DS9238-01 July 2001 Preliminary RT9238 www.richtek-ic.com.tw 21 ...

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... RT9238 Package Information C F Symbol www.richtek-ic.com.tw 22 Preliminary Dimensions In Millimeters Min Max 17.704 18.110 7.391 7.595 2.362 2.642 0.330 0.508 1.194 1.346 0.229 0.330 0.102 0.305 10.008 10.643 0.381 1.270 Dimensions In Inches Min Max 0 ...

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... RT9238 DS9238-01 July 2001 Preliminary www.richtek-ic.com.tw 23 ...

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... RT9238 RICHTEK TECHNOLOGY CORP. Headquarter 6F, No. 35, Hsintai Road, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5510047 Fax: (8863)5537749 www.richtek-ic.com.tw 24 Preliminary RICHTEK TECHNOLOGY CORP. Taipei Office (Marketing) 8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek-ic.com.tw ...