RT8450BGCP Richtek USA Inc, RT8450BGCP Datasheet
RT8450BGCP
Specifications of RT8450BGCP
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RT8450BGCP Summary of contents
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High Voltage Multi-Topology LED Driver General Description The RT8450 current mode PWM regulator for LED driving applications. With an 1.5A switch on board and wide input (4.5V to 40V) and/or output (up to 50V)ranges the RT8450/B can operate ...
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RT8450/B Typical Application Circuit V IN 4.5V to 40V 5V PWM Dimming control R1 10k C2 3nF V IN 4.5V to 40V Analog Dimming 5V R1 10k C2 3nF 4.5V to 40V PWM Dimming control 5V R1 10k C2 3nF ...
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V IN 4.5V to 40V 5V PWM Dimming control R1 10k C2 3nF Figure 4. PWM to Analog Dimming Boost Configuration V IN 4.5V to 40V 5V PWM Dimming control R1 10k C2 3nF Figure 5. PWM to Analog Dimming ...
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RT8450/B Pin No. TSSOP-16 WDFN-12L 3x3 (Exposed Pad 10, 11, 12 (Exposed Pad) 13 (Exposed Pad) 13 Function Block Diagram VCC1 OVP DCTL www.richtek.com 4 Pin ...
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Absolute Maximum Ratings Supply Input Voltage CC1, CC2 SW Pin Voltage at Switching Off, ISP, ISN ---------------------------------------------------------------------------- DCTL, ACTL, OVP Pin Voltage ------------------------------------------------------------------------------------------ 8V (Note 6) EN Pin Voltage --------------------------------------------------------------------------------------------------------------- 20V Power Dissipation 25°C ...
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RT8450/B Parameter LED Dimming Analog Dimming ACTL Pin Input Current LED Current Off Threshold at ACTL DCTL Input Current PWM BOOST Converter Switching Frequency Maximum Duty Cycle (Note 5) D Minimum on Time SW On-Voltage SW Current Limit OVP and ...
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Typical Operating Characteristics (ISP – ISN) Voltage vs. Input Voltage 200 198 196 194 192 190 188 186 184 182 180 Input Voltage (V) Supply Current vs. Input Voltage 5 4.5 4 3.5 3 2.5 ...
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RT8450/B LED Current vs. DCTL Duty 600 500 400 300 200 100 DCTL Duty (%) OVP vs. Input Voltage 1.220 1.215 1.210 1.205 1.200 Input Voltage (V) ACTL-Off vs. ...
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Switching Frequency vs. Input Voltage 900 800 700 600 500 400 Input Voltage (V) Power On from (10V/Div (5V/Div) V OUT (10V/Div) I OUT (100mA/Div) Time (250 Line Transient Response V IN ...
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RT8450/B Line Transient Response V IN (10V/Div) V OUT_ac (20V/Div) I OUT (100mA/Div) Time 1ms/Div) www.richtek.com 21V to 24V IN 6 LEDs Buck R = 0.25Ω ISET DS8450/B-02 November 2009 ...
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Application Information The RT8450/B is specifically designed to be operated in buck, buck -boost and boost converter applications. This device uses a fixed frequency, current mode control scheme to provide excellent line and load regulation. The control loop has a ...
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RT8450/B Over Temperature Protection The RT8450/B has over temperature protection (OTP) function to prevent the excessive power dissipation from overheating. The OTP function will shut down switching operation when the die junction temperature exceeds 150°C. The chip will automatically start ...
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Place the compensation components to the VC pin as close as possible to avoid noise pick up. Place these components as close as possible C OUT GND R SENS : : : GND Locate the ...
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RT8450/B Outline Dimension EXPOSED THERMAL PAD (Bottom of Package) Symbol www.richtek.com Dimensions In Millimeters Min Max 1.000 1.200 0.000 0.150 0.800 1.050 0.190 ...
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Symbol Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Information that is provided by Richtek Technology Corporation is believed to ...