rt9246 Richtek Technology Corporation, rt9246 Datasheet
rt9246
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rt9246 Summary of contents
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... The feature greatly facilitates the flexibility of CPU power supply design and tuning. The DAC output of RT9246 supports K8 CPU by 5-bit VID input, precise initial value & smooth V VID jump. The IC monitors the V and over-voltage protection. Soft-start, over-current ...
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... RT9246 Typical Application Circuit www.richtek.com 2 DS9246-06 March 2007 ...
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... IC power supply. Connect this pin supply Ω) initial value offset. Connect this pin to GND with a differential sense positive input. differential sense output. current sense inputs from converter 2 current sense inputs for individual converter current sense inputs from converter 1 RT9246 nd rd & 3 phase st channel www.richtek.com 3 ...
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... RT9246 Function Block Diagram www.richtek.com 4 DS9246-06 March 2007 ...
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... RT9246 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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... RT9246 Absolute Maximum Ratings Supply Voltage, V ------------------------------------------------------------------------------------------- 7V CC Input, Output or I/O Voltage ---------------------------------------------------------------------------------- GND-0. Power Dissipation 25° TSSOP-28 ------------------------------------------------------------------------------------------------------ 1W Package Thermal Resistance (Note 4) TSSOP-28, θ -------------------------------------------------------------------------------------------------- 100°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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... GBW SR I ISPFSS I ISPOCP 10k IMAX IMAX Δ OVT VSEN Rising V PGOOD− 4mA PGOODL PGOOD = 25° low effective thermal conductivity test board of A RT9246 Min Typ Max Units 2.2 2.4 2.6 V μ 0.95 1.0 1. MHz -- 3 -- V/μs ...
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... RT9246 Typical Operating Characteristics Current Balance (5V/Div) PWM2 PWM1 PWM3 I PWM2 I PWM1 I PWM3 (2.5A/Div) Time (1us/Div) Current Balance @ Soft Start (5V/Div) SS (5A/Div) I PWM1 I PWM2 I PWM3 Time (10ms/Div) DVD Disable (200mV/Div) DVD V (200mV/Div) CORE SS (1V/Div) PGOOD (500mV/Div) Time (2ms/Div) www.richtek.com 30A ...
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... SS (1V/Div) (5V/Div) (500mV/Div) (500mV/Div) OCP Power Up SS PWM I PWM3 Time (40ms/Div) Transient Response PWM1 PWM2 PWM3 V CORE Time (200us/Div Fly Rising SS2 (5V/Div CORE (500mV/Div) SS (500mV/Div) Time (200ns/Div) RT9246 I = short LOAD (5V/Div) (5V/Div) (5A/Div) www.richtek.com 9 ...
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... RT9246 V On Fly Falling 1nF SS2 CORE SS Time (200ns/Div) www.richtek.com 10 C SS2 (5V/Div (500mV/Div) V CORE (500mV/Div Fly Rising ID = 1nF (5V/Div) (500mV/Div) (500mV/Div) Time (200ns/Div) DS9246-06 March 2007 ...
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... For 2-Channel application, connect PWM3 high. of pulse width C Current Sensing Setting RT9246 senses the current of low side MOSFET in each synchronous rectifier when it is conducting for channel to output by IN current balance and droop tuning. The differential sensing GM amplifier converts the voltage on the sense component ...
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... local feedback. Protection and SS Function SP for channel 2 & 3 (at For OVP, the RT9246 detects the the differential amplifier output. Eliminate the delay due is sampled and held to compensation network (compared to sensing FB X voltage) for fast and accurate detection. The trip point of OVP is 140% of normal output level ...
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... DAC offset voltage setting (VOSS pin & compen sation network resistor). 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. RT9246 12V 12V V CORE 12V Current Sense Components www ...
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... RT9246 Design Example Given: Apply for three phase converter V = 12V 1.5V CORE I (max) = 60A LOAD V = 120mV at full load DROOP OCP trip point set at 30A for each channel (S/ 6mΩ of low side MOSFET at 27°C DS(ON 2μ 9,000μF with 2mΩ ESR. ...
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... The compensation, bypass and other function setting components should be near the IC and away from the noisy power path DS9246-06 March 2007 SW1 IN SW2 Figure 7. Power Stage Ripple Current Path ) ensures the accurate DS(ON OUT C OUT L2 RT9246 R L www.richtek.com 15 ...
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... C BOOT CORE C C OUT IN Kelvin Sense For Thermal Couple Figure 8. Layout Consideration PWM VCC C IMAX VOSS COMP C RT9246 ISPx R ISNx R SN VSEN ADJ GND DS9246-06 March 2007 + Next Locate next to FB Pin FB ...
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... No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek.com L A2 Dimensions In Inches Min Max 0.033 0.047 0.002 0.006 0.031 0.041 0.007 0.012 0.378 0.386 0.026 0.248 0.256 0.169 0.177 0.018 0.030 RT9246 www.richtek.com 17 ...