AMC1300: AC line current sensing

Nam, Dino

Expert 6325 points

Part Number: AMC1300
Other Parts Discussed in Thread: AMC3301, AMC3302, AMC1302

Dear team,

The customer would like to consider using AMC1300 for their application like below.

Is the AMC1300 available to sense AC line current with shunt? Is there any problem common mode voltage?

The customer application is AC/DC power supply of Air purifier like below.

- AC 110/220V, 50/60Hz

- output power : 60W

- Isolation is needed(mandatory)

Please let me know your opinion about this. If there is application note or other document related customer application, please let me know.

If AMC1300 is not right solution, could you recommend right solution(INA series or others) and application note to apply AC line current sensing or DC link line (over 300V) current sensing for customer application?

Thank you.

over 2 years ago

+1 kai klaas69 over 2 years ago

Guru 140200 points

Hi Nam,

yes, when you do it as shown in figure 51 of datasheet. Note, how GND1 is connected to the shunt to be able to decrease the common mode input voltage seen by the AMC1300 to the absolute minimum.

Kai

+1 Alexander Smith over 2 years ago

TI__Guru 51051 points

Hi Dino,

The AMC devices are designed for this type of measurement, the "working voltage" is the relevant specification for the high common-mode voltage.

This introductory article may help: https://www.electronicdesign.com/power-management/whitepaper/21130089/texas-instruments-introduction-to-isolated-amplifiers-and-modulators

AMC1300 has a 250mV input and the shunt should be sized such that voltage drop closely matches the input of the AMC. For high current applications, we also have the AMC1302 with a 50mV input to reduce the power dissipated in the shunt resistor. Both of these devices require a high voltage side power supply. We also have the AMC3301 and AMC3302 devices with an integrated DC/DC converter that will not require a discrete high voltage side power supply. This article may help: https://www.ti.com/lit/an/slyt810/slyt810.pdf

Please let me know if you have additional questions.

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

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AMC1300: AC line current sensing