Transformer Selection for iW1688 Solution

Transformer Selection for iW1688 Solution

iWATT China Applications & Supports

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VOUT (V)

NsNp

1. Confirm the transformer turns ratio

从横坐标找出所要设计电源的输出电压(VOUT)，就可以依据红色曲线查到变压器的匝比(NP/NS)。

Read :20.2Read :20.2

Example :Example :The output voltage is 5V.The output voltage is 5V.

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2. Confirm primary winding turns

Ae(mm2)

NP(Turns)

根据所用的磁芯的Ae，就可以依据红色曲线查到变压器初级的匝数(NP)。

Read : 214 TurnsRead : 214 Turns

Example :Example :A EE16 core, its A EE16 core, its AeAe is 18.5mmis 18.5mm22

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3. Confirm the primary inductance

OPP(W)

LM (mH)

根据电源的最大功率点(OPP)，就可以依据红色曲线查到变压器初级电感量(LM)。

Read : 2.4 Read : 2.4 mHmH

Example :Example :A Adapter with 5W output, its A Adapter with 5W output, its OPP will set at 130% or 6.5WOPP will set at 130% or 6.5W

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4. Input voltage protecting according to RIN

RIN(Ω)

VIN(VDC)

Input Over-Voltage Protection (OV) - DCV

Input Under-voltage Protection (UV) - DCV

Example :Example :The total RThe total RININ is set to 6Mis set to 6MΩΩ..

Read: The UV is 70VDCRead: The UV is 70VDC

Read: The UV is 443VDCRead: The UV is 443VDC