rt8803a Richtek Technology Corporation, rt8803a Datasheet

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... PWM Controller for High-Density Power Supply General Description The RT8803A is a 2/3-phase synchronous buck controller specifically designed to power Intel microprocessors. It implements an internal 8-bit DAC that is identified by VID code of microprocessor directly. RT8803A generates VID table that conform to Intel VRD11 core power with 6.25mV increments and 0.5% accuracy ...

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... RT8803A Typical Application Circuit All brandname or trademark belong to their owner respectively www.richtek.com 2 PWM2 TSEN PWM1 OFS FB FBRTN COMP SS VR_Ready IMAX VR_FAN RT VR_HOT VTT/EN ADJ DS8803A-05 August 2007 ...

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... DAC voltage identification inputs for VRD10.x / VRD11 / K8 / K8_M2 . These pins are internally pulled up to VTT. VIDSEL VID [7] VTT X GND X VDD NC VDD GND to RT GND [Exposed pad (33)] The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. RT8803A Table VR11 VR10.x K8 K8_M2 www.richtek.com 3 ...

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... RT8803A Function Block Diagram SS Soft Start & PGOOD VR_Ready COMP FB OFS VID7 VID6 VID5 VID4 DAC VID3 VID2 VID1 VID0 VID_SEL FBRTN TSEN Temperature VR_FAN Processing VR_HOT All brandname or trademark belong to their owner respectively www.richtek.com 4 VDD VTT/EN Power On Reset Current - EA Processing ...

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... RT8803A Nominal Output Voltage DACOUT VID6 1 1.60000V 0 1.59375V 1 1.58750V 0 1.58125V 1 1.57500V 0 1.56875V 1 1.56250V 0 1.55625V 1 1.55000V 0 1.54375V 1 1.53750V 0 1.53125V 1 1.52500V 0 1.51875V 1 1.51250V 0 1.50625V 1 1.50000V 0 1 ...

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... RT8803A Table 1. Output Voltage Program (VRD10.x + VID6) VID4 VID3 VID2 ...

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... RT8803A Nominal Output Voltage DACOUT VID6 1 1.11250V 0 1.10625V 1 1.10000V 0 1.09375V 1 OFF 0 OFF 1 OFF 0 OFF 1 1.08750V 0 1.08125V 1 1.07500V 0 1.06875V 1 1.06250V 0 1.05625V 1 1.05000V 0 1.04375V 1 1.03750V 0 1 ...

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... RT8803A Table 1. Output Voltage Program (VRD10.x + VID6) VID4 VID3 VID2 All brandname or trademark belong to their owner respectively www.richtek.com 8 Pin Name VID1 VID0 VID5 ...

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... RT8803A Nominal Output Voltage DACOUT 1.36875V 1.36250V 1.35625V 1.35000V 1.34375V 1.33750V 1.33125V 1.32500V 1.31875V 1.31250V 1.30625V 1.30000V 1.29375V 1.28750V 1.28125V 1.27500V 1.26875V 1.26250V 1.25625V 1.25000V 1.24375V 1.23750V 1.23125V 1.22500V 1 ...

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... RT8803A Pin Name Nominal Output Voltage DACOUT HEX 4E 1.12500V 4F 1.11875V 50 1.11250V 51 1.10625V 52 1.10000V 53 1.09375V 54 1.08750V 55 1.08125V 56 1.07500V 57 1.06875V 58 1.06250V 59 1.05625V 5A 1.05000V 5B 1.04375V 5C 1.03750V 5D 1.03125V 5E 1.02500V 5F 1.01875V 60 1.01250V 61 1.00625V 62 1.00000V 63 0.99375V 64 0.98750V 65 0.98125V 66 0.97500V 67 0.96875V 68 0.96250V 69 0.95625V 6A 0.95000V 6B 0.94375V 6C 0.93750V 6D 0.93125V 6E 0.92500V 6F 0 ...

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... RT8803A Nominal Output Voltage DACOUT ...

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... RT8803A Pin Name Nominal Output Voltage DACOUT HEX OFF FF OFF Note: ( Connected to GND ( Open ' ( Don t Care All brandname or trademark belong to their owner respectively www ...

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... RT8803A Nominal Output Voltage DACOUT 1.550 1.525 1.500 1.475 1.450 1.425 1.400 1.375 1.350 1.325 1.200 1.275 1.250 1.225 1.200 1.175 1.150 1.125 1.100 1.075 1.050 1.025 1.000 0.975 ...

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... RT8803A VID5 VID4 VID3 All brandname or trademark belong to their owner respectively www ...

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... RT8803A Nominal Output Voltage DACOUT VID0 0 0.7375 1 0.7250 0 0.7125 1 0.7000 0 0.6875 1 0.6750 0 0.6625 1 0.6500 0 0.6375 1 0.6250 0 0.6125 1 0.6000 0 0.5875 1 0.5750 0 0.5625 1 0.5500 0 0.5375 1 0 ...

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... RT8803A Absolute Maximum Ratings Supply Voltage, V ------------------------------------------------------------------------------------------- 7V DD Input, Output or I/O Voltage ---------------------------------------------------------------------------------- GND-0. Power Dissipation 25° VQFN−32L 5x5 -------------------------------------------------------------------------------------------------- 2.778W Package Thermal Resistance (Note 4) VQFN-32L 5x5, θ --------------------------------------------------------------------------------------------- 36°C/W JA Junction Temperature ------------------------------------------------------------------------------------------ 150°C Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------- 260°C Storage Temperature Range --------------------------------------------------------------------------------- −65°C to 150°C ...

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... DAC V ILDAC V IHDAC 100kΩ OFS OFS GBW SR COMP = 10pF I ISPFSS ΔOVT 20k IMAX IMAX 4mA PGOODL PGOOD = 25° low effective thermal conductivity test board of A RT8803A Min Typ Max −0.5 -- +0.5 − − − 1/ 0.9 1.0 1.1 ...

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... RT8803A Typical Operating Characteristics Frequency vs. R 700 600 500 400 300 200 100 Output Voltage vs. Temperature 1.264 1.262 1.26 1.258 1.256 1.254 1.252 1.25 1.248 - Temperature (°C) Power On from DVD DVD (1V/Div) SS (1V/Div) V OUT (1V/Div) PHASE 3 (10V/Div) Time (1ms/Div) All brandname or trademark belong to their owner respectively www ...

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... DS8803A-05 August 2007 Power Off from VCC12 VCC12 (10V/Div) SS (1V/Div) V OUT (1V/Div) PHASE 3 (10V/Div) Time (1ms/Div) Power Off from VCC5 VCC5 (5V/Div) SS (1V/Div) V OUT (1V/Div) PHASE 3 (10V/Div) Time (25ms/Div) Output Short Circuit VR_Ready (1V/Div) SS (2V/Div) V OUT (1V/Div) PWM (5V/Div) Time (1ms/Div) RT8803A www.richtek.com 19 ...

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... RT8803A V OUT V OUT (20mV/Div) I OUT (40A/Div) Time (2μs/Div) Dynamic VID V OUT (200mV/Div) VID0 (500mV/Div) Time (50μs/Div) VR_Ready (1V/Div) SS (2V/Div) FB (1V/Div) PWM (5V/Div) Time (10μs/Div) www.richtek.com 20 Droop (20mV/Div) (200mV/Div) (500mV/Div) OVP All brandname or trademark belong to their owner respectively V Overshoot ...

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... The RT8803A initiates only after 3 pins are ready: VDD pin power on reset (POR), VTT/EN pin enabled, and DVD pin is higher than 1V. VDD POR is to make sure RT8803A is powered by a voltage for normal work. The rising threshold voltage of VDD POR is 4.2V typically. At VDD POR, RT8803A checks PWM3, PWM4 and PWM5 status to determine phase number of operation ...

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... The sampled and held phase current I averaged to get the averaged current current I The difference between I corresponding PWM comparator. If phase current I smaller than the averaged current , RT8803A increases the duty cycle of corresponding phase to increase the × DCRx phase current accordingly and vice versa. ...

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... R FB1 V CORE V DAC Figure 4. Load Line and Offset Function Output Voltage Offset Function ® To meet Intel requirement of initial offset of load line, RT8803A provides programmable initial offset function. External resistor R and voltage source at OFS pin OFS V = generate offset current I OFS R , where typical. One quarter of I ...

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... (A) 80 100 120 Referring to Figure 11 where make sure RT8803A could sense the inductor current, X CSN right hand side of Equation (1) should always be positive: to sense the voltage. X and X Since R could be simplified as : Load Line without dead zone at light loads 1.31 1.3 w/o Dead Zone Compensation 1 ...

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... R line will be thermally compensated CMP Over Current Protection - CC + Phase current OCP Q2 CMP - CC RT8803A uses an external resistor R + IMAX pin to generate a reference current I Q3 CMP - CC current protection : where V each sensed phase current I as shown in Figure 15. Equivalently, the maximum phase current I Temperature / R ...

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... RT8803A Error Amplifier Characteristic For fast response of converter to meet stringent output current transient response, RT8803A provides large slew rate capability and high gain-bandwidth performance. EA Falling Slew Rate V FB CH1:(500mV/Div) V COMP CH2:(2V/Div) Time (250ns/Div) Figure 16. EA Rising Transient with 10pF Loading ; ...

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... Email: marketing@richtek.com SEE DETAIL DETAIL A Pin #1 ID and Tie Bar Mark Options Dimensions In Inches Min Max 0.031 0.039 0.000 0.002 0.007 0.010 0.007 0.012 0.195 0.199 0.134 0.148 0.195 0.199 0.134 0.148 0.020 0.014 0.018 RT8803A www.richtek.com 27 ...