RT9284A-20GJ6E Richtek USA Inc, RT9284A-20GJ6E Datasheet
RT9284A-20GJ6E
Specifications of RT9284A-20GJ6E
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RT9284A-20GJ6E Summary of contents
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... Tiny Package, High Performance, Constant Current Switching Regulator for White LED General Description The RT9284A compact, high efficient and high integration LED driver. Internal 22V MOSFET can support White LEDs for backlighting and camera flashing. Highly integration and internal compensation network minimizes as 5 external component counts ...
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... Figure 2. Application for Driving 4 Series WLEDs L1 4.7uH to 22uH C1 1uF RT9284B 6 LX VDD 4 EN OVP 2 100Hz-100kHz GND FB Figure 3. Application for Driving 5 Series WLEDs L1 4.7uH to 22uH C1 1uF RT9284A 6 1 VDD OVP 2 3 GND FB Figure 4. Application for Constant Output Voltage D1 OVP SS0520 15V C2 I LED ...
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... Leave it unconnected to disable this function. Supply Input Voltage Pin. Bypass 1uF capacitor to GND to reduce the input noise. 1.2MHz OSC Current Bias ibias OCP 750mA V BandGap REF Protection Circuit OVP UVLO Timer 5ms Soft Start RT9284A/B Pin Function PWM Logic LX + Buffer - REF GND www.richtek.com 3 ...
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... Reference Voltage Feedback Voltage (Note 5) www.richtek.com 4 (Note 1) (Note 3) Symbol Test Condition 1.5V, No switch 0V, Switch < 0. 3.0~4. OSC RT9284A RT9284B − 65°C to 150°C − 40°C to 125°C − 40°C to 85°C Min Typ Max Units 2.7 -- 5.5 1.8 2.2 2.5 50 300 1000 0 ...
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... JEDEC 51-3 thermal measurement standard. Note 5. Floating the OVP pin to disable OVP function. DS9284A/B-06 June 2009 Symbol Test Condition R DS(ON) for 2,3,4 WLEDs application V OVP for 5 WLED application 25° low effective thermal conductivity test board of A RT9284A/B Min Typ Max Units -- 0. μ ...
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... RT9284A/B Typical Operating Characteristics Enable Voltage vs. Input Voltage 1.2 1.1 -45°C 1.0 25°C 0.9 85°C 0.8 0.7 0.6 0.5 3 3.25 3.5 3.75 4 Input Voltage (V) Efficiency vs. Input Voltage 20mA 4.7μH, DCR = 0.15Ω LED 83.5 3WLEDs 83 82.5 4WLEDs 82 81.5 81 80.5 3 3.2 3 ...
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... IN (100mA/Div) I LED (10mA/Div) Time (400μs/Div) DS9284A/B-06 June 2009 -45°C 25°C 85°C 4.25 4.5 4.75 5 5.25 5.5 = 20mA 10μ 1kHz, Duty = 50% RT9284A/B Switching Frequency vs. Temperature 1.5 1.45 1.4 1.35 1.3 1.25 1.2 1.15 1.1 1.05 1 -40 -30 -20 - Temperature (°C) Dimming Operation 4WLEDs ...
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... RT9284A/B Dimming Operation 4WLEDs 3.7V LED EN (5V/Div (100mA/Div) (10mA/Div) I LED Time (4μs/Div) Inrush Current 4WLEDs 3.0V LED (2V/Div) EN (2V/Div (5V/Div) V OUT I IN (100mA/Div) Time (500μs/Div) Normal Operation (5V/Div) (2V/Div) V OUT (10V/Div (100mA/Div) Time (400ns/Div) www.richtek.com 8 = 20mA 10μ 100kHz, Duty = 50% = 20mA 4.7μ ...
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... Normal Operation (5V/Div) (2V/Div) V OUT (10V/Div (100mA/Div) Time (400ns/Div) DS9284A/B-06 June 2009 4WLEDs 4. 20mA 10μH LED V OUT V RT9284A/B Normal Operation (5V/Div) (2V/Div) 4WLEDs LED (10V/Div (100mA/Div) Time (400ns/Div 20mA 10μH www.richtek.com 9 ...
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... RT9284A/B Application Information Power Sequence The RT9284A/B must take notice of the power sequence. The power sequence of RT9284A/B has to VDD early than EN or else the RT9284A/B maybe fall into the unknown state to result in RT9284A/B turn off > 1.5V EN < 0. OUT Figure 5 LED Current Control ...
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... X5R and X7R types are suitable because of their wider voltage and temperature ranges. R2 10k Diode Selection R3 R1 10k 110 Schottky diode is a good choice for RT9284A/B because its low forward voltage drop and fast reverse recovery. 3k 1uF Using Schottky diode can get better efficiency. The high- ...
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... RT9284A/B Figure 10. Bottom Layer www.richtek.com 12 DS9284A/B-06 June 2009 ...
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... TSOT-23-5 Surface Mount Package RT9284A Dimensions In Inches Min Max 0.028 0.039 0.000 0.004 0.055 0.071 0.012 0.022 0.102 0.118 0.106 0.122 0.033 0.041 ...
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... RT9284A/B 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 be accurate and reliable. Richtek reserves the right to make any change in circuit design, specification or other related things if necessary without notice at any time. No third party intellectual property infringement of the applications should be guaranteed by users when integrating Richtek products into any application ...