rt8800 Richtek Technology Corporation, rt8800 Datasheet
rt8800
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rt8800 Summary of contents
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... The RT8800/B apply the time sharing DCR current sensing technology newly as well; with such a topology, the RT8800/B extract the DCR of output inductor as sense component to deliver a more precise load line regulation and better thermal balance capability. ...
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... PWM1 , PWM2 , PWM3 PWM outputs for each phase switching drive. VDD Chip power supply. Connect this pin supply. rising. DVD GND Chip power ground. Exposed Pad (RT8800) Exposed pad should be soldered to PCB board and connected to GND. VDD 16 PWM2 DACFB 2 15 ...
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... The inductor’ s DCR value must be large than 0.3mΩ : X7R/R-type capacitor is required for all time constant setting capacitor of DCR sensing.) All brand name or trademark belong to their owner respectively DS8800/B-06 March 2007 15 PWM1 ISP1 1 VDD ICOMMON COMP DVD Figure A. 2-phase with resistive DAC RT8800 www.richtek.com 3 ...
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... RT8800/B All brand name or trademark belong to their owner respectively www.richtek.com 4 NC LGATE2 PVCC2 PHASE2 UGATE2 PWM1 13 16 VDD ICOMMON COMP Figure B. 3-phase with resistive DAC VDD LGATE1 PVCC1 PHASE1 UGATE1 12 ISP1 DVD DS8800/B-06 March 2007 ...
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... All brand name or trademark belong to their owner respectively DS8800/B-06 March 2007 NC LGATE2 PVCC2 PHASE2 UGATE2 13 PWM1 16 VDD COMP Figure C. 3-phase with RT9401A/B DAC generator RT8800/B VDD LGATE1 PVCC1 PHASE1 UGATE1 12 ISP1 8 ICOMMON DVD www.richtek.com 5 ...
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... RT8800/B Function Block Diagram All brand name or trademark belong to their owner respectively www.richtek.com 6 Mux DS8800/B-06 March 2007 ...
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... RT8800/B VID0 Nominal Output Voltage (V) 1 1.0800 0 1.1000 0 1.1125 1 1.1250 1 1.1375 0 1.1500 0 1.1625 1 1.1750 1 1.1875 0 1.2000 0 1.2125 1 1.2250 1 1.2375 0 1.2500 0 1.2625 1 1.2750 1 1.2875 0 1 ...
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... RT8800/B VID5 VID4 Note Open GND SS All brand name or trademark belong to their owner respectively www.richtek.com 8 Table. Output Voltage Program VID3 VID2 VID1 ...
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... All brand name or trademark belong to their owner respectively DS8800/B-06 March 2007 (Note 1) (Note 3) Symbol Test Conditions PWM 1,2,3 Open 16kΩ OSC RT f OSC_ADJ Δ 16kΩ OSC 16kΩ RT8800/B + 0.3V DD Min Typ Max Units -- 4.0 4.2 4.5 V 0.2 0 0.75 0.8 0. 170 ...
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... RT8800/B Parameter Reference Voltage Reference Voltage DACFB Sourcing Capability Error Amplifier DC Gain Gain-Bandwidth Product Slew Rate Current Sense GM Amplifier Recommended Full Scale Source Current OCP trip level Protection Over-Voltage Trip ( DACQ Power Good PGOOD Output Low Voltage PGOOD Delay Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for stress ratings ...
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... All brand name or trademark belong to their owner respectively DS8800/B-06 March 2007 = 10kΩ 100Ω DROOP V = 12V 100 (kΩ 110 125 RT8800/B Efficiency vs. Output Current 100 ...
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... RT8800/B Frequency vs. Temperature 350 300 250 200 150 100 50 0 -25 - Temperature (°C) Load Transient Response V CORE (200mV/Div) UGATE1 (20V/Div) UGATE2 (20V/Div) UGATE3 (20V/Div) phase2 85A @SR = 93A/us) OUT Time (2.5μs/Div) Over Current Protection (50A/Div) V CORE (1V/Div) ...
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... OUT CORE (50mV/Div) PWM (5V/Div (200mV/Div) V ID0 (2V/Div OUT PWM (5V/Div) V CORE (200mV/Div (200mV/Div) V ID0 (2V/Div) RT8800 the Fly Falling 90A OUT Time (25μs/Div the Fly Rising 90A OUT Time (10μs/Div) www.richtek.com 13 ...
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... EA output and split-phase sawtooth wave. Power stage transforms V Output Voltage Program The output voltage of a RT8800/B converter is programmed to discrete levels between 1.08V and 1.85V. The voltage identification (V reference (DACQ) with a 6-bit digital-to-analog converter (DAC). The level of DACQ also sets the OVP threshold. ...
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... Figure 1. The Structure of Discrete DAC Generator DAC Design Guideline In high temperature environment, V unstable for the leakage current in VID pins is increasing. The leakage will increase current consumption of CPU, and then raise RT8800's V DACQ V voltage. Below are four comparison charts for CORE different CPUs. ...
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... In order to maintain the V within 1% tolerance in the DACQ worst case, the total driver current of the DAC regulator should support up to 40mA. As the design of RT8800/B, the maximum driving current of the internal OP is 10mA. As shown in Figure 6, we suggest to add an external transistor 2N3904 for higher current for V 1 ...
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... )/R times current than other phases 1.5uH 1m 3k 1uF 3k Figure 13. GM3 Setting for current ratio function I L 1.5uH 1m 1.5k 1uF Figure 14. GM1,2 Setting for current ratio function RT8800/B ⎞ + ⎟ ⎠ DCR www.richtek.com 17 ...
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... V C ICOMMON1 Current Balance RT8800/B senses the inductor current via inductor’ s DCR for channel current balance and droop tuning. The differential sensing GM amplifier converts the voltage on the sense component (can be a sense resistor or the DCR of the inductor) to current signal into internal balance circuit ...
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... Over Current Protection OCP comparator co\mpares each inductor current sensed & sample/hold by current sense circuit with this reference current(150uA). RT8800/B uses hiccup mode to eliminate fault detection of OCP or reduce output current when output is shorted to ground. All brand name or trademark belong to their owner respectively ...
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... RT8800/B Design Procedure Suggestion a.Output filter pole and zero (Inductor, output capacitor value & ESR). b.Error amplifier compensation & sawtooth wave amp- litude (compensation network). Current Loop Setting a.GM amplifier S/H current (current sense component DCR, ICOMMON pin external resistor value). b.Over-current protection trip point (R VRM Load Line Setting a ...
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... Reduce parasitic minimum length, enough copper thickness and avoiding of via. 3. MOSFET driver should be closed to MOSFET All brand name or trademark belong to their owner respectively DS8800/B-06 March 2007 SW1 C IN SW2 Figure 22. Power Stage Ripple Current Path RT8800 OUT C OUT www.richtek.com 21 ...
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... All brand name or trademark belong to their owner respectively www.richtek.com 22 +12V or +5V C BOOT CORE C OUT C IN Figure 23. Layout Consideration Figure 24 PWM VCC RT COMP GND RT8800/B R ICOM ICOMMON FB R CSPx PI GND DS8800/B-06 March 2007 + Next Locate next to FB Pin ...
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... All brand name or trademark belong to their owner respectively DS8800/B-06 March 2007 Figure 25 Figure 26 RT8800/B www.richtek.com 23 ...
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... RT8800/B All brand name or trademark belong to their owner respectively www.richtek.com 24 Figure 27 DS8800/B-06 March 2007 ...
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... V-Type 16L QFN 3x3 Package RT8800 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 ...
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... RT8800 Symbol Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 All brand name or trademark belong to their owner respectively www.richtek.com Dimensions In Millimeters Min Max 9.804 10.008 3.810 3 ...