AMC1301-Q1: TPSI2140QDWQRQ1

Hi Ramesh and welcome to the forum!

I would recommend going for a split-tap connection with your GND, as your inputs are floating and not in reference to the high-side GND of your design. For further information, please refer to the following document: Split-Tap Connection for Line-to-Line Isolated Voltage Measurement Using AMC3330

Additionally, the AMC1300 is the latest drop-in replacement to the AMC1301 and provides better isolation and performance ratings when compared to the AMC1301. I would recommend electing the AMC1300 over the AMC1301 for your design.

After making those recommended adjustments, if possible, would you be able to come back and repost once you have obtained values for your components? We're interested in following up and seeing results. Thank you and please let me know if you have any additional questions.

Hi Ramesh,

You need a connection from the input divider to the AMC1300 GND1 pin, but I can't see one on your schematic:

See Joel's split tap connection:

Also if you use AMC3330 it includes DCDC so you would not need U1.

Please check the modifed schematic

Hi Ramesh,

I'll note that Ken's recommendation has some benefits. The AMC3330 would help in removing the gain error by placing the sensing resistor in parallel with the differential input impedance. You can utilize this Excel calculator to compare the two and calculate the expected difference in accuracy between the two: https://www.ti.com/lit/zip/sbar013

Furthermore, there are some challenges in using a device with low input impedance to sense a high impedance node, so there will be an expected gain error using the AMC1300. However, for your purposes, I gauge that the AMC1300 will be sufficient. This concept is expanded upon in this document: Isolated Voltage-Measurement Circuit With ±250-mV Input and Differential Output

Additionally, I believe you can also get rid of your old sensing resistor(R161) and the diode in parallel to that as well. Also consider adding small capacitors (around 100pF) for anti-aliasing filtering on the inputs. If you could get back to me with specific values for the resistors and capacitors, we’d be able to run a more thorough evaluation of your design. Until then, reach out if you have further questions regarding part choices or if you require supporting documentation.

Hi Joel,

Please find the modification and components detail ,value of Resistor is calculated from excel sheet given by you.

Calculated Components Value : Max Input Voltage :850V DC (Battery String Voltage)

(1) R35,R37,R39,R41--- 499 K 1% melf  0207

(2)  R36,R38,R40,R42 ---DNM  Melf 0207

(3) R44,R46 --619 K 1% Melf 0207

(4) R45 ------------DNM MELF 0207

(5) R47,R159 ---10 R 1% 1206

(6) C23 -----------10 pF 1206

We are open to discuss of new cost effective solution/ part  suggested by you also.

With Regards...

Ramesh Gupta

Cofounder/CTO

OgoEnergy India Pvt Ltd

Hi Ramesh,

Could I ask that you take another capture of your circuit? The resolution is too low to make anything out clearly. It can be a PDF like the original schematic you shared. Also, in order to properly simulate the circuit, I would require that all capacitor and resistor values be included in your design. If you require any tools to obtain any specific values, please notify me and I will try and share any documents or software that can aid you. 

If your applications are limited to DC only, I can recommend the AMC1311 which can handle a 2-V input. Please note I can't make any final decisions related to your design, but I will do my best to provide you with information that can aid you, so please direct to me any specific questions that can help you in choosing or operating TI products. The more information you can provide to me or include in your design, the better I can tailor to your needs. 

Thank You Joel,

What is your availability as per Indian Standard time for tomorrow , so that we  can do fast this design process.

I am always welcome your suggested part number and design . I have no Issue to use AMC1311 and will change the design if require.

it will be better if we discuss on zoom or whatsapp for speed up the my  development.

Please check the schematic with AMC1301, and suggest 8507.eBCU-Voltage.pdf

Thank U Joel for your kind support

With Regards,,,

Ramesh Gupta

Hi Ramesh!

We're based in the US, central time so you are 10.5 hours ahead of us.  Zoom or whatsapp are not really options for us, but if a call is necessary we might be able to set something up via WebEx for an early evening call your time. 

As Joel mentioned, you would be better off using the AMC1311 where you would have a 0-2V input swing to the amplifier.  Where does the TPSI2140 fit into this equation and what is the part number for U1?  You will also need biasing on your OPA33xxDBV (U17) to get the full scale range from the amplifier output.

Hi Tom,

U1 is DC-DC regulator --Its input is +5V DC and output is +5V Isolated .

MornSun Part Number :B0505S-1wr3

Application Name: Energy Storage Solution-

Product Name: Battery Control Unit 

I have two object 

(1) Measurement of High Voltage DC

(2) Measurement of Isolation in Reference to Earth-Chassis Ground.

2450.eBCU-Voltage.pdf

pdf and schematic screen shot is shared for your reference.

I am available from 9:00 PM to 11:00 PM IST,Please share the webex link if it is OK for you.

With Regards...

Ramesh Gupta

Contact Number:+919811332717

Hi Joel, 

Request to check attached schematic for measurement of High Voltage DC with AMC13111665.eBCU-Voltage.pdf

 i am waiting for response  

Hello Ramesh,

I have contacted you via email. Please direct your responses accordingly. Thank you.