RT8206L RICHTEK [Richtek Technology Corporation], RT8206L Datasheet

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... Other features include Diode- Emulation Mode (DEM), which maximizes efficiency in light-load applications, and fixed frequency PWM mode, which reduces RF interference in sensitive application. The RT8206L/M is available in a WQFN-32L 5x5 package. Ordering Information RT8206 Package Type QW : WQFN-32L 5x5 (W-Type) ...

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... RT8206L/M Marking Information RT8206LGQW RT8206LGQW : Product Number RT8206L YMDNN : Date Code GQW YMDNN RT8206LZQW RT8206LZQW : Product Number RT8206L YMDNN : Date Code ZQW YMDNN Pin Configurations REF 1 TON 2 VCC 3 ENLDO 4 GND NC 5 VIN 6 LDO WQFN-32L 5x5 RT8206L © ...

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... LGATE1 REF 9 BYP 13 PGOOD1 10 VOUT1 28 PGOOD2 3 14 VCC EN1 27 EN2 4 ENLDO 12 ILIM1 20 SECFB/ ILIM2 FB1 32 2 TON FB2 29 SKIP 19 PVCC 21, 33 (Exposed Pad) GND 7 LDO Figure 1. Fixed Voltage Regulator is a registered trademark of Richtek Technology Corporation. RT8206L OFF www.richtek.com 3 ...

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... RT8206L © Copyright 2012 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 RT8206L UGATE2 VIN 24 BOOT2 15 UGATE1 25 PHASE2 17 BOOT1 23 LGATE2 22 PGND 16 PHASE1 30 18 VOUT2 LGATE1 32 FB2 9 BYP 1 REF 10 VOUT1 13 PGOOD1 3 28 VCC PGOOD2 14 EN1 27 EN2 4 ENLDO 20 SECFB/NC 12 ILIM1 31 ILIM2 11 FB1 ...

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... Comp + Over-Voltage Fault + Latch - - Blanking Time + Under-Voltage - SS + Time 25kHz Detector Zero Detector PWM Controller (One Side registered trademark of Richtek Technology Corporation. RT8206L/M BOOT2 UGATE2 PHASE2 PV CC LGATE2 VOUT2 FB2 ILIM2 PGOOD2 VCC PVCC ENLDO EN1 EN2 REF REF T OFF 1-Shot Q ...

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... RT8206L/M Functional Pin Description REF (Pin 1) 2V Reference Output. Bypass to GND with a 0.22μF capacitor. REF can source up to 50μA for external loads. Loading REF degrades FBx and output accuracy according to the REF load-regulation error. TON (Pin 2) Frequency Select Input. (VOUT1/VOUT2 switching ...

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... PVCC to VCC. Make sure that both VCC and PVCC are bypassed with 1μF MLCC capacitors. SECFB (Pin 20) (RT8206L) Charge Pump Feedback Input. The SECFB is used to monitor the optional external charge pump. Connect a resistive voltage-divider from the charge pump output to GND to detect the output ...

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... RT8206L/M VOUT2 (Pin 30) SMPS2 Output Voltage Sense Input. Connect this pin to the SMPS2 output. VOUT2 is an input to the constant on-time-PWM one-shot circuit. It also serves as the SMPS2 feedback input in fixed-voltage mode. ILIM2 (Pin 31) SMPS2 Current-Limit Adjustment. The GND − PHASE2 current limit threshold is 1/10th the voltage seen at ILIM2 over a 0 ...

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... Input Voltage, VIN ----------------------------------------------------------------------------------------------- 6V to 25V Junction Temperature Range ---------------------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range ---------------------------------------------------------------------------------- −40°C to 85°C © Copyright 2012 Richtek Technology Corporation. All rights reserved. DS8206L/M-07 June 2012 (Note 1) (Note registered trademark of Richtek Technology Corporation. RT8206L/M + 0.3V 0.3V 0.3V) CC www.richtek.com 9 ...

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... FB1= GND, IN OUT1 SKIP 25V, FB2 = V IN OUT2 SKIP 25V (RT8206L) SECFB IN SMPS1, SMPS2 Fixed or Adj-Mode comparator threshold Either SMPS, SKIP = V Either SMPS, SKIP = REF LOAD Either SMPS, SKIP = GND Either SMPS 25V LINE IN SMPS1 = 5 ...

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... PGOOD Detect, FBx Falling edge Rising Edge with Soft-Start Delay Time Falling Edge High State, Forced to 5. 4mA SINK OVP Detect, FBx Rising edge FB_OVP FBx with 50mV Overdrive UVP Detect, FBx Falling edge From ENx Enable SHDN RT8206L/M Min Typ -- 4700 0 0. ILIMx = 1V 85 ...

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... ENx TON SKIP FBx (RT8206L) SECFB PVCC to BOOTx BOOTx to PHASEx Forced to 5V, High State BOOTx to PHASEx Forced to 5V, Low State LGATEx, High State LGATEx, Low State LGATE Rising UGATE Rising Min Typ -- -- ...

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... CC ENLDO = V , FB1 = GND IN 0 Ultrasonic Mode V = 12V, TON = EN2 = V , EN1 = GND, CC ENLDO = V , FB2 = GND IN 0 RT8206L/M VOUT1 Efficiency vs. Load Current 100 90 DEM Mode Ultrasonic Mode 50 40 PWM Mode EN2 = GND, EN1 = V 10 ENLDO = V 0 0.001 0.01 0.1 Load Current (A) VOUT2 Efficiency vs ...

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... RT8206L/M VOUT1 Switching Frequency vs. Load Current 250 V = 7V, TON = V , EN2 = GND, EN1 = 225 ENLDO = V , FB1 = GND IN 200 PWM Mode 175 150 125 100 75 50 Ultrasonic Mode 25 DEM Mode 0 0.001 0.01 Load Current (A) VOUT1 Switching Frequency vs. Load Current 250 V = 25V, TON = V , EN2 = GND, EN1 = V ...

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... ENLDO = registered trademark of Richtek Technology Corporation. RT8206L/M V vs. Output Current REF V = 12V, EN1 = EN2 = GND, ENLDO = Output Current (μA) Standby Current vs. Input Voltage 216 No Load, EN1 = EN2 = GND, ENLDO = V 214 ...

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... RT8206L/M Power On from VIN V IN (10V/Div) LDO (5V/Div) REF (2V/Div) CP (10V/Div) No Load 12V, TON = V IN EN2 = GND, ENLDO = V Time (400μs/Div) Power On from EN1 PWM Mode EN1 (5V/Div) V OUT1 (5V/Div (5A/Div) PGOOD1 (5V/Div) TON = V EN1 = V CC, CC Time (1ms/Div) Power On from EN2 ...

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... LOAD IN , ENLDO = (10V/Div) (20V/Div) , ENLDO = (50mV/Div) , ENLDO = V , FB1 = RT8206L/M Power On from EN1 (Delay Start) EN2 = REF EN1 (5V/Div) EN2 (5V/Div) V OUT1 (2V/Div) V OUT2 (2V/Div 12V, TON = V IN Time (400μs/Div) Power Off from EN1 ...

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... RT8206L/M VOUT1 (5V/Div) PGOOD1 (5V/Div) VOUT2 (5V/Div) PGOOD2 (5V/Div 12V, TON = Time (500μs/Div) Power On in Short Circuit VOUT1 (500mV/Div Short OUT1 I L1 (10A/Div) UGATE1 (20V/Div) LGATE1 (5V/Div 12V, TON = Time (400μs/Div) © Copyright 2012 Richtek Technology Corporation. All rights reserved. ...

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... TM The DRV mode PWM modulator is specifically designed to have better noise immunity for such a dual output application. The RT8206L/M achieves high efficiency at a reduced cost by eliminating the current-sense resistor found in traditional current-mode PWMs. Efficiency is further enhanced by its ability to drive very large synchronous rectifier MOSFETs. The RT8206L/M includes 5V (LDO) linear regulator which can step down the battery voltage to supply both internal circuitry and gate drivers ...

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... RT8206L/M Operation Mode Selection The RT8206L/M supports three operation modes: Diode- Emulation Mode, Ultrasonic Mode, and Forced-CCM Mode. Users can set operation mode by SKIP pin. All of the three operation modes will be introduced as follows. Diode-Emulation Mode (SKIP = GND) In Diode-Emulation mode, the RT8206L/M automatically reduces switching frequency at light-load conditions to maintain high efficiency ...

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... R DS(ON) D The current limit threshold is adjusted with an external resistor for the RT8206L/M at ILIMx. The current limit threshold adjustment range is from 50mV to 200mV. In the adjustment mode, the current limit threshold voltage is precise to 1/10 the voltage seen at ILIMx. The threshold defaults to 100mV when ILIMx is connected to VCC. The logic threshold for switchover to the 100mV default value is higher than VCC− ...

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... UGATEx PHASEx Figure 5. Reducing the UGATEx Rise Time Soft-Start The RT8206L/M provides an internal soft-start function to prevent large inrush current and output voltage overshoot when the converter starts up. The soft-start (SS) automatically begins once the chip is enabled. During soft-start period, the internal current limit circuit gradually ramps up the inductor current from zero ...

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... Power Up Sequencing and On/Off Controls (ENx) EN1 and EN2 control SMPS power-up sequencing. When the RT8206L/M applies in the single channel mode, EN1 or EN2 enables the respective outputs when ENx voltage rises above 2.5V, and disables the respective outputs when ENx voltage falls below 1 ...

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... RT8206L/M capacitors by a sudden load step. The peak amplitude of the output transient ( also a function of the SAG maximum duty factor, which can be calculated from the on-time and minimum off-time : ⎛ Δ 2 × × ⎜ LOAD ⎝ SAG ⎡ × × ...

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... If the layout is designed improperly, the PCB could radiate excessive noise and contribute to the converter instability. The following guidelines must be strictly followed for a proper layout of RT8206L/M. Connect an RC low-pass filter from PVCC to VCC. The RC low-pass filter is composed of an external capacitor and an internal 10Ω ...

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... RT8206L/M Mode Power Up PVCC < UVLO threshold ENLDO = high, EN1 or EN2 RUN enabled Over voltage Either output > 112% of nominal Protection level. Either output < 55% of nominal level Under voltage after 3ms time-out expires and Protection output is enabled. Either SMPS output is still high in Discharge either standby mode or shutdown mode ...

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... W-Type 32L QFN 5x5 Package RT8206L/M SEE DETAIL DETAIL A Pin #1 ID and Tie Bar Mark Options Dimensions In Inches Min Max 0.028 0.031 0.000 0.002 0.007 ...