DRV8306: Recommended External Components values and connections

Onawa-San,

1. 22nF is correct, the EVM also uses this value.
2. The VM capacitor does not need to be a specific value but we recommend a small cap (0.1uF) for noise decoupling and a bigger cap (1uF, 4.7uF, etc) for bulk capacitor purposes.
3. Please download the EVM files, they show there that the AGND, PGND, and power pad are all connected together at the DRV.

Regards,

-Adam

Hi Adam-san,

I have a request on the schematic and layout... Could you send me EVM schematic and layout by pdf file? I can't open special format files because we can't freely install the software on my PC now. 

Also, Please follow the questions below.

Are the AGND, PGND, and power pads connected inside the device?

According to the material contents below, conductive Silver die attach past is used for DRV8306. My customer want to know which  GND power pad connected to, AGND or PGND internally?

https://www.ti.com/materialcontent/en/report?pcid=238995&opn=DRV8306HRSMR

Regards,

Takashi Onawa

Onawa-San,

Inside the design files the PDF is included. I have added it here for your convenience: /cfs-file/__key/communityserver-discussions-components-files/38/MD009E1_2800_001_29005F00_Sch.PDF

I am not certain how the grounds are connected inside the device but our recommendation is to connect the power pad, AGND, and PGND to the same system board GND.

If the customer has specific questions about the grounding please let me know and we can address them.

Regards,

-Adam

Hi Adam-san,

Thanks for sharing the schematic.

As the background of this question, Power GND and other GND are separated on my customer's board. So they wanted to know which GND the thermal pad should be connected.

Could you check that to designer?

Regards,

Takashi Onawa

Hi Adam-san,

Could you tell me the status of your confirmation?

Regards,

Takashi Onaw

Hi Adam-san,

Can you tell us what's going on?

Regards,

Takashi Onawa

Hi Adam-san,

If we do not complete this check early, we will lose this socket.
I need to do some escalation if necessary, but before I do that, could you comment on the current status of the confirmation?

Regards,

Takashi Onawa

Onawa-San,

I will respond by end of business today.

Regards,

-Adam

Onawa-San,

I would recommend connecting the thermal pad to the PGND. If the grounds are separated on the customer's board then PGND would still need to be connected to AGND near the DRV device.

Regards,

-Adam

Hi Adam-san,

Thanks. I understood.

One quick question, Are there any app note describing such the GND connection?

Regards,

Takashi Oanwa

Onawa-San,

Unfortunately no, we don't have an app note for this.

Regards,

-Adam

Hi Adam-san,

Thanks for your strong assist on this.

I understood. I will close this thread once. 

Regards,

Takashi Onawa