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enter image description hereI am experimenting with energy harvesting using electromagnetic induction.

I am using the [LTC3108(Ultralow Voltage Step-Up Converter and Power Manager) circuit.

==>http://cds.linear.com/docs/en/datasheet/3108fc.pdf

I have a few questions.

  1. My input signal is AC 0.8V. Does this circuit allow AC input?

  2. Is a rectifier included in this circuit? Because I have to convert AC to DC.

  3. The red part uses a transformer to convert dc to ac.

In my case, omit this part and enter ac directly.

If you enter ac in the circuit, will the circuit work?

enter image description here

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  • \$\begingroup\$ That was an indirect link. I've fixed it. (Hit the edit button to see how the link is embedded.) I've also added an image. That way people can see immediately what you are talking about. Please edit your post to explain where the 0.8 V AC is coming from. \$\endgroup\$ – Transistor Oct 19 '17 at 11:16
  • \$\begingroup\$ Why did you remove the circuit schematic and mess up the hyperlink? \$\endgroup\$ – Transistor Oct 19 '17 at 11:54
  • \$\begingroup\$ Possible duplicate of Energy Harvesting Circuit Questions \$\endgroup\$ – winny Oct 19 '17 at 16:44
  • \$\begingroup\$ @Jeong You have two similar questions, either delete one or merge them. Thanks \$\endgroup\$ – Voltage Spike♦ Oct 20 '17 at 16:18
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enter image description here

Figure 1. Extract from the datasheet.

  1. My input signal is AC 0.8V. Does this circuit allow AC input?

According to the datasheet the answer is no.

  1. Is a rectifier included in this circuit? Because I have to convert AC to DC.

No.

If you have an AC source you have the option of stepping up the voltage with a transformer. There isn't enough information in your question to comment on whether this is possible.

Update:

  1. The red part uses a transformer to convert dc to ac. In my case, omit this part and enter ac directly. If you enter ac in the circuit, will the circuit work?

No. Notice that the transformer is 1:100. The FET switches on and creates a DC pulsed current through the transformer. This input voltage is stepped up by a factor of 100 to create a useable voltage on the other side. Feeding 0.8 V directly in will be useless. Feeding a negative voltage into SW will destroy the chip.

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  • \$\begingroup\$ 1. Is this circuit capable of DC input only? 2. I need to convert ac to dc and raise the voltage. Which IC should I use? \$\endgroup\$ – Jeong Jeong Hoon Oct 19 '17 at 11:49
  • \$\begingroup\$ The opening paragraph of the datasheet says, "The LTC3108 is a highly integrated DC/DC converter ideal for harvesting and managing surplus energy from extremely low input voltage sources such as TEGs (thermoelectric generators), thermopiles and small solar cells." \$\endgroup\$ – Transistor Oct 19 '17 at 11:51
  • \$\begingroup\$ My input voltage is the voltage generated by the electromagnetic induction. Is this circuit unsuitable? I'll attach the resulting waveform. \$\endgroup\$ – Jeong Jeong Hoon Oct 19 '17 at 11:53
  • \$\begingroup\$ What part of the the -0.3 V absolute max is unclear? What part of DC/DC is unclear? It is not suitable for your application. \$\endgroup\$ – Transistor Oct 19 '17 at 11:55
  • \$\begingroup\$ I found the following circuit. Is it a circuit suitable for my input? digikey.com/product-detail/en/advanced-linear-devices-inc/… \$\endgroup\$ – Jeong Jeong Hoon Oct 19 '17 at 11:55

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