RT9241A RICHTEK [Richtek Technology Corporation], RT9241A Datasheet
RT9241A
Related parts for RT9241A
RT9241A Summary of contents
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... The feature greatly facilitates the flexibility of CPU power supply design and tuning. The RT9241A/B uses a 5-bit DAC of 1.1V to 1.85V (25mV/step) output with load current droop compensation to meet the strict VRM transient requirement. The IC ...
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... RT9241A/B Typical Application Circuit www.richtek.com 2 DS9241AB-05 March 2007 ...
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... DS9241AB-05 March 2007 RT9241A/B www.richtek.com 3 ...
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... RT9241A/B Function Block Diagram VDD PGOOD 120% VDAC VID0 VID1 108% DAC VID2 VDAC VID3 VID4 92% VDAC VSEN ADJ FB GND www.richtek.com 4 DVD Power On Reset + INH - OVP, PGOOD + POR Logic - + - Current Limit Droop Control Oscillator INH PWM Logic + & Driver - PWMCP INH ...
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... DS9241AB-05 March 2007 PWM1 (Pin 17), PWM2 (Pin 16) PWM outputs for each driven channel. Connect these pins to the PWM input of the MOSFET driver. PGOOD (Pin 19) Power good open-drain output. VDD (Pin 20) IC power supply. Connect this pin supply. RT9241A/B www.richtek.com 5 ...
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... RT9241A/B VID4 VID3 Note: (1) 0:Connected to GND (2) 1:Open www.richtek.com 6 Table 1 Output Voltage Program ...
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... DAC (VID0-VID4) Input High Voltage DAC (VID0-VID4) Bias Current PWM Controller Error Amplifier DC Gain Bandwidth Slew Rate DS9241AB-05 March 2007 Symbol Test Conditions PWM 1,2 Open I DD RT9241A For each phase RT9241B C = 10pF L RT9241A/B +0.3V DD 110°C /W − 40°C to 150°C Min Typ Max Units -- 4.2 4.35 4 ...
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... RT9241A/B Parameter Current Sense GM Amplifier ISP 1,2 Full Scale Source Current ISP 1,2 Current for OCP Protection SS Current Over-Voltage Trip (VSEN/DACOUT) Power Good Upper Threshold (VSEN/DACOUT) Lower Threshold (VSEN/DACOUT) www.richtek.com 8 Symbol Test Conditions VSEN Rising VSEN Rising Min Typ Max Units μA ...
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... Time (5us/Div) The Hysteresis of V 1.6 1.4 1.2 1 0.8 0.6 0.4 0 DS9241AB-05 March 2007 Up 20A/Div (V) RT9241A/B Over Current Protection at Steady State PWM1 PWM2 OUT Time (25ms/Div) Two-Phase Converter without Current Sharing PWM1 PWM2 Time (5us/Div) The Hysteresis of VDVD 1.6 1.4 1.2 1 0.8 0.6 0.4 0 ...
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... RT9241A/B Simplified Block Diagram Control Loops for a Two Phase Converter VDAC ADJ + FB - GND COMP Voltage Loop www.richtek.com 10 Droop Current Control Balance Processor EA SS Control LOAD OUT PWM Logic + PWM1 & Driver - PWMCP PWM2 PWM Logic + & Driver - PWMCP ...
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... V PWM output to driver input for correct converter start- up. Current sensing setting RT9241A/B senses the current of low side MOSFET in each synchronous rectifier when it is conducting for channel current balance and droop tuning. The differential sensing GM amplifier converts the voltage on the sense ...
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... Protection and SS function For OVP, the RT9241A/B detects the V is sampled and held just Eliminate the parasitic delay and noise influence on the PCB path for fast and accurate detection. The trip point of OVP is 120% of normal output level. The PWM outputs ...
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... GND PWM2 DVD SS ISP2 ISN2 Power sequence & SS DVD pin external resistor and SS pin capacitor PCB layout a.Kelvin sense for current sense GM amplifier input b.Refer to layout guide for other item RT9241A/B 12V VCC BOOT PVCC UGATE PHASE RT9600 PWM LGATE GND ...
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... RT9241A/B Design Example for RT9241A Two phase converter V = 1.5V, V CORE current = 40Amp, droop voltage at full load = 120mV, OCP trip point for each power stage = 30Amp (at Sample/ Hold), low side MOSFET R temperature 2μH, C OUT ESR = 2mΩ. 1.Compensation setting a. Modulator Gain, Pole and Zero ...
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... MOSFET 4.The compensation, bypass and other function setting SW1 SW2 Figure.7 Power Stage Ripple Current Path RT9241A/B a.Input capacitor to high side MOSFET b.Low side MOSFET to output capacitor c.The return path of input and output capacitor d.Separate the power and signal GND e ...
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... Each Channel to help Isolate Output Stages BOOT CORE C C OUT IN Kelvin Sense Parallel Trace Locate next Figure.8 Layout Consideration PWM VCC ADJ COMP RT9241A SIP ISPx ISNx R SIN VSEN to IC DS9241AB-05 March 2007 + Next to IC Pin( ...
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... Lead SOP Plastic Package Richtek Technology Corporation Taipei Office (Marketing) 8F, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek.com RT9241A Dimensions In Inches Min Max 0.496 0.512 0.291 0.299 ...