FAN5235QSC Fairchild Semiconductor, FAN5235QSC Datasheet
FAN5235QSC
Specifications of FAN5235QSC
FAN5235QSC_NL
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FAN5235QSC Summary of contents
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FAN5235 System Electronics Regulator for Mobile PCs Features • Synchronous rectification • ±1% precision internal reference • >90% efficiency • Input and output voltage feedback • 5.4V to 24V input voltage range • Internally set 300kHz ±15% oscillator • 5V ...
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FAN5235 Pin Assignments 3.3V-ALWAYS 5V-ALWAYS Pin Description Pin Name Pin Number Pin Function Description VIN 1 Input power. 3.3V-ALWAYS 2 3.3V Always on linear regulator. Load current on pins 2 and 6 must not exceed 50mA total. CPUMP3.3 3 Charge ...
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Pin Description (Continued) Pin Name Pin Number Pin Function Description ISEN5 21 Current Sense for 5V. This pin should be connected to the drain of the bottom Mosfet using appropriate resistor and RC filter. See Application Section. SW5 22 High ...
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FAN5235 ELECTRICAL SPECIFICATIONS Operating Conditions Recommended Operating Conditions Unless Noted Refers to Block Diagrams Parameter Supply V Input Supply Voltage IN Input Quiescent Current Input UVLO Threshold 5V and 3.3V Main Regulators Output Voltage Precision Oscillator Frequency, f osc HSD ...
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Operating Conditions (Continued) Recommended Operating Conditions Unless Noted Refers to Block Diagrams Parameter 12V Regulator (Continued) On Output 5V-Always GS Off Output Ramp Amplitude, pk-pk Error Amplifier GBW Under Voltage Shut Down Over Voltage Shut Down ...
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FAN5235 CLK GATE LOGIC PWM VFB – ERROR AMP VREF – LSD ISEN – + Figure 1. FAN5235 5V/3.3V Internal Block Diagram of PWM Loop CK Ramp PWM VREF=2.5V R Ramp 16R V out ...
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ALWAYS 5V ALWAYS Figure 3. FAN5235 5V/3.3V—ALWAYS Internal Block Diagram Functional Description The FAN5235 is a high efficiency and high precision DC/DC controller for notebook and other portable applications. It provides all of the voltages necessary for system electronics: ...
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Peak current is DC output current plus peak ripple current: TV 4µsec • • 5µH 2L where T is the maximum period output voltage, and L O ...
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Under-voltage Protection When the output voltage of either the 3. falls below 75% of the nominal value, both converters, go into under- voltage (UV) protection, after a 2usec delay. In under- voltage protection, the high ...
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FAN5235 Error Amplifier output voltage clamp During a load transient the error amplifier voltage is allowed full swing. After two clock cycles, if the amplifier is still out of range the voltage and consequently the duty cycle (DC) is clamped. ...
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FAN5235 Notebook Application Circuit 3.3V@50mA C10 5V@50mA C11 3.3V@ C12, C13 Q2 SDN3.3 C3 +5V R1 PGOOD Figure 8. FAN5235 Notebook Application Circuit Table 1. FAN5235 Application Bill of Materials Reference Manufacturer, Part # ...
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FAN5235 MOSFET Selection The notebook application circuit shown in Figure 1 is designed to run with an input voltage operating range of 5.4-24V. This wide input range helps determine the selection of the MOSFETs for the 3.3V and 5V converters, ...
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Mechanical Dimensions QSOP 24-Lead Inches Millimeters Symbol Min. Max. Min. 0.0532 1.35 A 0.0668 A1 0.0040 0.0098 0.1 A2 0.054 0.062 1.37 b 0.008 0.012 0.20 c 0.0075 0.0098 0.19 D 0.337 0.344 8.55 E 0.150 0.157 3.81 e 0.025 ...
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FAN5235 Mechanical Dimensions TSSOP 24-Lead Inches Millimeters Symbol Min. Max. Min. A — .047 — A1 .002 .006 0.05 B .007 .012 0.19 C .004 .008 0.09 D .303 .316 7.70 E .169 .177 4.30 e .026 BSC 0.65 BSC ...
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... FAN5235 Ordering Information Product Number Package FAN5235QSC 24 Lead QSOP FAN5235MTC 24 Lead TSSOP DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS ...