TPA3123D2: Use as constant voltage source

Hi Sven,

Actually we do have some dedicated devices for coolers and heaters. Have you taken a look at DRV591, DRV592, DRV593, DRV594, and DRV595? 

These might prove to be easier to implement in your system! Let me know what you think. 

Best Regards,

Robert Clifton

Hi Robert,

thank you for providing these alternative devices. Indeed they look easier to implement. Unfortunately I fear 5.5V is too low (specifications aren't fixed, yet). The DRV595 is very expensive, thus not my favorite.

The device will be driven by a SimpleLink µC. Thus a digital PWM interface might be an option, too. I'm currently considering the TAS5342, but I'm somewhat unhappy about the 12V extra supply (There are 48V, 18V, 5V, 3.3V, 2.5V, 1.1V available on the pcb to be extended.) and its rather big package. On the other hand it is able to drive 2 coolers / heaters.

What's your opinon about TAS5342? Is it worth further investigation for this application?

Hi Sven,

I wouldn't be the person you would want to discuss pricing with but I could help with the more technical details! Haha.

Can you share more details on the system? As you mentioned not all of the specifications aren't fixed yet but can you tell me which ones are so I can better direct you a part that would be well suited to your application? 

Regards,

Robert Clifton

Hi Robert,

to tell you the truth the project is in a very early stage and our company is mainly driven by optics and mechanics. Nevertheless I try to guide things into the right direction from an electronics point of view. Due to the quite thin cabling to the peltier cooler and the quite powerful 18V and 48V supply on the existing pcb I'd like to use a relatively high voltage for the cooler maybe 12V. The peltier current will be very likely <2A. There will be two coolers to be controlled. The remaining space on the pcb is limited, thus two inductors of about 10µH seem to be feasible but 1mH as required by many motor drivers not.

I'm sorry that I can only give you such vague information.

Do you have any concerns w.r.t. TAS5342?

Hi Sven,

Earlier engagement is always better then being too late! 

You mentioned that there's limited space on the board but you chose a pad-up device that will require a heatsink. Is choosing a device with a heatsink ok for your application or would you prefer to have a pad-down? 

TAS5342 isn't recommended for new designs but we do have the TAS5342LA. The TAS5342LA max current is 8.4A which seems to be a bit higher than what you are looking for? 

Regards,

Robert Clifton

Hi Robert,

you are right, actually I consider using TAS5342LA. (I was not aware of 'LA' being important.) A heatsink could be acceptable but is not preferred. My hope was that losses in the device will be small enough to omit the heatsink.But I just read about the idle power of 3W and ambient temperature could be up to 40°C ...

If you know an alternate device with lower losses or pad-down please let me know.