AMC1200-Q1: Application design of AMC1200-Q1

Hi Poh,

keep in mind that the AMC1200 provides a voltage output. See figure 14 of datasheet. But you wire it as a current output with a 10mR shunt between the output pins. This will short circuit the signal.

Kai

Hi Smith,

The magnitude of the current to be measure is around 0.68A .

The 5V will be get from a discrete isolated DC/DC converter.

Here my correction design and what value Rshunt will be appropriate?

 My Vin is 110V dc input, what the equation should be to measure the Vout?

thank you.

Best regards,

ku 

Hi Smith,

I don't see the power supply update nor your voltage sensing circuit.

-You means my connection of VDD1 should not connect to Vin=110Vdc? 

If i change the VDD1 connection to below new connection (connect to 12Vout of 110V to 12V DC/DC module), is it correct?

Can i use the above design to measure the voltage and current of Vin=110Vdc line ?

Thank you.

Best regards,

Ku

Hi Smith,

May I know which parts of the design is incorrect?

The input of the VDD1 or somewhere else?

thank you.

regards, 

Ku

Hi Ku,

Yes - VDD1 is not correctly designed. 

"As GND1 will be connected to the high voltage line, 5V will not be derived for VDD1. You may need to consider designing a discrete isolated DC/DC converter such as what's present on the AMC1200EVM: https://www.ti.com/tool/AMC1200EVM , a device with integrated DC/DC converter such as AMC3301, or switching to current sensing on Vin- and deriving a 5V supply using LDO's from the Vin+ voltage."

Hi Smith,

Hope my update schematic are correct now.

Do my AMC1200 output can direct connect to INA236 as my schematic?

I plan to use INA236 to measure the current and voltage.

Thank you.

Best regards.

Ku