This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

EM1402EVM: Support

Part Number: EM1402EVM
Other Parts Discussed in Thread: TMS570LS0432, TMS570LS1224, BQ76PL455A, BQ76PL455EVM

I am interested in purchasing EM1402EVM & I have a few queries regarding this product. My questions are:-

Context:- I am planning on using this product on a 14S 12P Battery pack. Monitoring, Balancing and SOC Estimation by means of Kalman filter are needed to be performed.

1) The forward converter transformer is connected across a 12V battery. Is it possible to connect this transformer across the battery that is being monitored (like in EM1401EVM)

2) The external Micro-controller suggested is TMS570LS0432. Will this micro-controller support a Kalman filter algorithm needed for SOC estimation (along with monitoring and balancing programs required for EM1402EVM). Or do i need to buy the more powerful TMS570LS1224?

3) Should the GUI software be purchased separately or is it a part of the product on purchase?

4) Apart from a PC that runs the GUI software, TMS570LS launch Pad and EM1402EVM Module, is it necessary to purchase any other additional hardware/software?

Thank you in advance.

  • Hi Kartik,
    1. The DC-DC converter must be designed for the voltage used. The EM1402 was designed for the 12V isolated battery which allows balancing between modules. The EM1401 was designed for balancing to the module voltage, so balancing between modules is not possible. If you have the single 14S pack the EM1401 type structure is more appropriate. The isolation circuitry could connect to the same voltage reference as the module, but the voltage is wrong. I don't know if it is practical to alter the components to get the board to work at the higher voltage.
    2. The TMS570 experts would be better able to help with features and code space.
    3. The active cell balancing is controlled by an external MCU, there is not a GUI for active cell balancing. The GUI for the bq76PL455A is available on the web from the EVM folder bq76PL455EVM or www.ti.com/.../sluc584, but it does not control active cell balancing.
    4. The EM1402EVM includes a UART interface to the PC if you wish to use the bq76PL455EVM GUI. You may need an interface and software to work with the TMS570, please refer to its product information.
  • Thank you for your response.

    I agree with you on EM1401EVM better suiting my requirement compared to EM1402EVM. However my concern is with the LM3S5R31 micro-controller used in EM1401EVM. It is obsolete and no longer in production. Hence I wont be able to find a replacement of this micro-controller in case of any accident and not much support is available for this product when compared to TMS570LS series used in EM1402EVM.

    As a follow up, I have some more questions:
    1)Is it possible to replace the micro-controller in EM1401EVM with any other micro-controller (with the same number of pins and general specifications) which is active in production, after i purchase the board?

    2) I understand that the source code for monitoring and balancing of cells is already present in the micro-controller of EM1401EVM. Is it possible to access and alter this code? If not, can we write our own code for monitoring and balancing on the micro-controller?

    Thank You.

  • Hi Kartik,
    The EVMs are reference designs for demonstration and won't always match your needs. The EM1401EVM is presently available but has parts which are no longer available, so it is not a good basis for a current design. The concepts and available parts are good, but would need to be applied to a system design. The EM1402EVM is the current reference design, it demonstrates additional capability for the active balancing parts - the external 12V for module to module balancing, as well as moving the MCU off the board and using a newer cell monitor. For the new specific questions:
    1. You are free to use the board as you wish within the disclaimers. Replacing a MCU seems difficult, the interface to the circuit is not very compact (it is not a 2, 4 or 10 wire bus). I would expect changing the transformer on the EM1402 as well as sensing and possibly interface to make it a 50V bus and connecting across the module would be easier, but I have not done either one. The intent of the EVM boards is to show operation of the parts rather than make a platform for modification, although sometimes modification is easy. Once you understand component operation and interaction with the EVM you are better prepared to design what you need on your own board.
    2. The EM1401EVM source code is not available. The same concepts are available in the EM1402EVM Example Code available in the product folder or the TIDM-TMS570BMS reference design although these do not provide the CAN interface.