FR9885 – Synchronous Step-Down DC/DC Converter

Part Number : FR9885

Function : Synchronous Step-Down DC/DC Converter

Manufactures : Fiti

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FR9885 image

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Description :

Lily 0755-83234073 159 153 736 32 Q Q 100 754 5980 fitipower integrated technology lnc. FR9885 18V, 2A, 500KHz Synchronous Step-Down DC/DC Converter Description The FR9885 is a synchronous step-down DC/DC converter that provides wide 4.5V to 18V input voltage range and 2A peak load current capability. At light load condition, the FR9885 can operate at PSM mode to support high efficiency and reduce power loss. The FR9885 fault protection includes cycle-by-cycle current limit, UVLO, output overvoltage protection and thermal shutdown.The internal soft-start function prevents inrush current at turn-on. This device uses current mode control scheme which provides fast transient response. Internal compensation function reduces external compensation components and simplifies the design process. In shutdown mode, the supply current is about 1µA. The FR9885 is offered in SOT-23-6 package and provides good thermal conductance. Pin Assignments S6 Package (SOT-23-6) Features Low Rds(on) Integrated Power MOSFET (170mΩ/135mΩ) Internal Compensation Function Wide Input Voltage Range: 4.5V to 18V Adjustable Output Voltage Down to 0.6V 2A Peak Output Current 500kHz Switching Frequency Internal 0.8ms Soft-Start Cycle-by-Cycle Current Limit Hiccup Short Circuit Protection Over-Temperature Protection with Auto Recovery OVP and UVLO SOT-23-6 Package Applications STB (Set-Top-Box) LCD Display, TV Distributed Power System Networking, XDSL Modem Ordering Information FR9885□□□ TR: Tape/Reel C: Green Package Type S6: SOT-23-6 Figure 1. Pin Assignment of FR9885 SOT-23-6 Marking Part Number FR9885S6CTR Product Code A9A FR9885-Preliminary 0.3-MAY-2014 1 fitipower integrated technology lnc. Typical Application Circuit FR9885 Figure 2. CIN /COUT use Ceramic Capacitors Application Circuit Figure 3. CIN /COUT use Electrolytic Capacitors Application Circuit VIN=12V, the recommended BOM list is as below. VOUT C1 R1 R2 1.2V 10µF MLCC 4.99kΩ 4.99kΩ 1.8V 10µF MLCC 30.9kΩ 15.4k 2.5V 10µF MLCC 30.9k 9.76k 3.3V 10µF MLCC 30k 6.65k 5V 10µF MLCC 30.9k 4.22k 1.2V 100µF EC 4.99kΩ 4.99kΩ 1.8V 100µF EC 30.9kΩ 15.4k 2.5V 100µF EC 30.9k 9.76k 3.3V 100µF EC 30k 6.65k 5V 100µF EC 30.9k 4.22k C5 10µF MLCC 10µF MLCC 10µF MLCC 10µF MLCC 10µF MLCC 0.1µF 0.1µF 0.1µF 0.1µF 0.1µF C4 10pF~1nF 10pF~1nF 10pF~1nF 10pF~1nF 10pF~1nF —— Table 1. Recommended Component Values FR9885-Preliminary 0.3-MAY-2014 L1 3.3uH 4.7uH 6.8uH 6.8uH 10uH 3.3uH 4.7uH 6.8uH 6.8uH 10uH C2 22µF MLCC x2 22µF MLCC x2 22µF MLCC x2 22µF MLCC x2 22µF MLCC x2 100µF EC 100µF EC 100µF EC 100µF EC 100µF EC 2 fitipower integrated technology lnc. FR9885 Functional Pin Description Pin Name BST GND FB SHDN VIN LX Pin No. 1 2 3 4 5 Pin Function High side gate drive boost pin. A capacitance between 10nF to 100nF must be connected from this pin to LX. It can boost the gate drive to fully turn on the internal high si […]

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FR9885 Datasheet

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