EMB1499Q: Charging can output normally, discharging can not output.

Hi Chime,

Can you follow the instructions of the last post please and confirm the waveforms are identical in your setup?

"It's interesting that you are not seeing any fault in the device. The discharge signals do look different than expected. Since the device is not triggering a fault, I would recommend to focus on the board components or any traces/connections that might be different between your new board (not working board) and your older version of the board (working board) by testing both. I recommend to compare the signals on both working and non-working boards to find any differences and trace the problem that way. You can use signals on figure 7 in the datasheet as to how the 4 signals (GATE_LS, GATE_HS1, GATE_HS2, PWM_CLAMP) need to look when discharging."

Regards,

Taylor

My malfunction is exactly as he described. I'm just not as lucky as he is, because I didn't debug a circuit board that could discharge.

My circuit and PCB are completely borrowed from EM-1402, without any modification.

I want to know, what controls the timing of the discharge? Why is the output of GATE _ HS2 not in the manual? It does not appear to be controlled by EMB1499.

Hi chime,

So you have all identical components to the reference design as well? Can you share the schematic?

Have you checked this reference for further details? https://www.ti.com/lit/ug/sluuas6a/sluuas6a.pdf

Regards,

Taylor

Hi Taylor,

I download the www.ti.com/.../tidrn63 directly.

My project is still in the design stage, so I am doing functional testing. I debugged it separately by circuit unit.

I am currently debugging the PWR580a _ ACB _ Isolated circuit in Tidrn63.

See the following figure for the lap welding circuit:

Thanks!

chime

Sluuas6a. Pdf I have also read it carefully.

The output waveform during discharge is as shown in the figure:

Hi Taylor,

Thank you for your reply!

I seem to have found the problem.

I'll debug it again to see if the output current is normal.

The driver timings are now correct. As shown in figure:

Thank you!

Chime

The main reason is that the electronic load I use may not be matched. I set the electronic load to CV mode, and the actual charge output will go to 6V, and discharge will go to 48V. The CV pattern is not constant or the response is too slow. This results in protection or burnout of the component, which eventually fails to work properly.  It is normal to use the battery as a load.