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ADuM3471, light load question.

Question asked by ColinL on Mar 4, 2013
Latest reply on Mar 5, 2013 by bkennedy

Hello,

 

Please advise on what is required to enable a system with a very low total standby power.

Our customer is making progress in creating a demo using ADUM3471 .

He writes:

In reading through the documentation and checking out the hardware, I have one concern. The documentation (Table 9, datasheet) talks about loading the isolated supply created by the ADuM347x device with at least 10mA otherwise regulation issues can occur. In my system I'm using the double supply portion since I need about 12V on the secondary. When I measure the supply voltage though it is running at about 14.5V. For now I can work around this, but I'm wondering if is possibly being caused by too little load on the isolated supply?

 

With no load I also saw about 14.5V on the 12V supply.

 

For the demo the load on the isolated supply includes LEDs and the like that will not be present in the final system. I will need to keep the load as low as possible so the standby current of the system is below regulatory requirements.

 

Thanks,

Colin Lee

Avnet FAE

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