RT8253B RICHTEK [Richtek Technology Corporation], RT8253B Datasheet
RT8253B
Related parts for RT8253B
RT8253B Summary of contents
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... Fault conditions also include output under voltage protection and thermal shutdown protection. The low current (<3μA) shutdown mode provides output disconnect, enabling easy power management in battery- powered systems. The RT8253B is available in a SOP-8 (Exposed Pad) package. Ordering Information RT8253B ...
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... Connect a series RC network from COMP to GND. In some cases, an additional capacitor from COMP to GND is required. Chip Enable (Active High). A logic low forces the RT8253B into shutdown mode reducing the supply current to less than 3μA. Attach this pin to VIN with a 100kΩ pull up resistor for automatic startup. ...
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... Function Block Diagram VIN Internal Regulator Shutdown VA V Comparator 1. Lockout Comparator 2. 6µA SS DS8253B-02 March 2011 Oscillator CC Foldback Control 0. Comparator + 0. COMP Current Sense Amplifier Slope Comp + - S Q 85mΩ 85mΩ - Current Comparator RT8253B VA BOOT SW GND www.richtek.com 3 ...
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... RT8253B Absolute Maximum Ratings Supply Voltage, V ------------------------------------------------------------------------------------------------- IN Input Voltage, SW --------------------------------------------------------------------------------------------------- −0. ----------------------------------------------------------------------------------------------------------- −0. BOOT SW Other Pin Voltages ------------------------------------------------------------------------------------------------- −0. Power Dissipation 25° SOP-8 (Exposed Pad) --------------------------------------------------------------------------------------------- 1.333W Package Thermal Resistance (Note 2) SOP-8 (Exposed Pad), θ ---------------------------------------------------------------------------------------- 75°C/W JA SOP-8 (Εxposed Pad), θ ...
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... Note 4. The device is not guaranteed to function outside its operating conditions. DS8253B-02 March 2011 Symbol Test Conditions Rising 0.1μ 25° high effective thermal conductivity four-layer test board of A RT8253B Min Typ Max Unit 2 0.4 3.8 4.2 4 320 -- mV μA ...
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... RT8253B Typical Operating Characteristics Efficiency vs. Output Current 100 12V 23V 0.01 0.1 Output Current (A) Reference Voltage vs. Temperature 0.820 0.815 0.810 0.805 0.800 0.795 0.790 0.785 V = 12V 0.780 -40 -25 - Temperature (°C) Frequency. vs. Input Voltage 1.40 1.35 1.30 1.25 1.20 1.15 1.10 1.05 1. ...
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... Current Limit vs. Temperature 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 -50 - Temperature (°C) Load Transient Response OUT I OUT (2A/Div 12V 3.3V OUT Time (100μs/Div) Switching V OUT 12V Time (500ns/Div) RT8253B V = 12V 3.3V IN OUT 50 75 100 125 = 0. OUT = 3.3V OUT OUT www.richtek.com 7 ...
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... RT8253B Switching V OUT (5mV/Div (10V/Div (2A/Div 12V Time (500ns/Div) Power Off from VIN V IN (5V/Div) V OUT (2V/Div (2A/Div 12V Time (5ms/Div) Power Off from (5V/Div) V OUT (2V/Div (2A/Div 12V Time (5ms/Div) www.richtek.com 8 V (5V/Div) ...
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... IN4148 or BAT54. The external 5V can fixed input from system output of the RT8253B. Note that the external boot voltage must be lower than 5.5V ...
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... For the RT8253BH, it provides Hiccup Mode Under Voltage Protection (UVP). When the FB voltage drops below half of the feedback reference voltage, V will be triggered and the RT8253BH will shut down for a period of time and then recover automatically. The Hiccup Mode UVP can reduce input current in short-circuit conditions ...
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... EMI improvement. Moreover, reducing the SW trace area and keeping the main power in a small loop will be helpful on EMI performance. For detailed PCB layout guide, please refer to the section of Layout Consideration. RT8253B . At best, this ringing can couple to the output IN large enough to damage the ...
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... 75k 22µFx2 2.2nF 22k 24k 64°C/W. Even further 49°C/ For RT8253B packages, the Figure 2.2 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 Ambient Temperature (°C) Figure 7. Derating Curves for RT8253B Package DS8253B-02 March 2011 V OUT 3.3V/3A OUT is 75°C/W. ...
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... Copper Area = 50mm (e) Copper Area = 70mm Figure 6. Themal Resistance vs. Copper Area Layout Design DS8253B-02 March 2011 Layout Consideration For best performance of the RT8253B, the follow layout guidelines must be strictly followed. Input capacitor must be placed as close to the IC as possible. , θ should be connected to inductor by wide and short = 75° ...
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... RT8253B GND Input capacitor must be placed as close to the IC as possible. C OUT V OUT Table 3. Suggested Capacitors for C Location Component Supplier MURATA C IN TDK C IN TAIYO YUDEN C IN MURATA C OUT TDK C OUT MURATA C OUT TDK C OUT www.richtek.com GND BOOT 8 VIN 2 7 GND ...
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... Y 3.000 3.500 8-Lead SOP (Exposed Pad) Plastic Package Richtek Technology Corporation Taipei Office (Marketing) 5F, No. 95, Minchiuan Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)86672399 Fax: (8862)86672377 Email: marketing@richtek.com RT8253B Dimensions In Inches Min Max 0.189 0.197 0.150 0.157 ...