TP-Link’s Tapo P115: Smart plug subtracts Apple, adds energy tracking

Take a baseline device, remove a subsequently added protocol and replace it with a function, and…you end up with a bigger-than-expected revision?

As I alluded to in a blog post a week-and-a-half back, I’m nearing the finish line of my teardown series on TP-Link smart plugs. As I mentioned last month, my basic aspiration with this project is to ascertain to what degree (if any) differences in the company’s various smart plug products’ feature sets, broadly between the Kasa and Tapo product lines as well as between products within a given line, are due to hardware variability versus (or in addition to) software-implemented inconsistency.

As such, today’s entry ended up being a deviation from the to-date norm, therefore a pleasant surprise. But I don’t want to ruin it for all of you via a premature reveal, so I’ll keep my cyber-lip zipped for the moment. Here’s the so-far published dissection list:

Revisiting another last-month comment, again note that hardware changes can be driven not only by evolving feature set requirements but also by phaseout and replacement of building block components inside these devices. To wit, hold that thought.

Unpacking the patient(s)

Today’s dissection victim is TP-Link’s Tapo P115, a two-pack of which set me back $13.77 during a Thanksgiving 2025 Amazon Resale (formerly Warehouse) used-goods promotion.

Like last month’s Tapo P125, it shares a common form factor with the baseline Tapo P105 I took apart in early June, with the exception of both successors’ relocation of the status LED to the side of the device, merged with the switch.

But as the above “stock” photo highlights, whereas the Tapo P125 had built on the Tapo P105 foundation with added Apple Homekit support, today’s Tapo P115 instead focuses its enhancement energy on energy monitoring and logging specifically. As such, it’s conceptually akin to the prior-gen Kasa EP25, again with energy monitoring, that went “under the knife” back in March.

What, if any, hardware commonality exists between the Kasa EP25 and Tapo P115? As well as, for that matter, between the Tapo P105 and Tapo P115? Let’s find out, as usual starting with some outer box shots, again accompanied by a 0.75′′/19.1 mm diameter U.S. penny for size comparison purposes.

The Amazon Resale-origination identifying sticker added to the bottom panel left unobscured the hardware version, v1.6. TP-Link’s support page indicates that this is the latest-and-greatest revision, with a v1.26 predecessor. Why do I care about such seeming minutia? I’ll remind you of my early-March coverage of the Kasa EP10, wherein I detailed (for the first time, but definitely not the last) version-based functional shortcomings both in an absolute sense and in “smart home”-striving combination with same-name devices containing different-version hardware.

Picking which patient

As was the case last month, opening the packaging and perusing the contents revealed evidence of prior-customer access and device removal, leading me to select that same device for analysis (the one on the left, if not already obvious).

Last month’s noted cuteness continues unabated, of course.

And now, finally free from its cardboard captivity, here’s our patient.

Once again, as is the case with the box containing it, the device’s bottom side is the most informative perspective, revealing factoids including the always-helpful FCC ID (2BCGWP110).

Diving inside

Here’s a vendor-supplied conceptual cutaway to whet your appetite for what’s next (regular readers of my teardowns already know how much I love coming across and sharing these).

How closely (or not) does this marketing creation (or abomination?) match what our eyes see when they peruse the actual insides? Let’s find out.

The inside of the back half of the enclosure is, as usual, bland and boring (unless you’re a plastics specialist, I suppose).

The other half, on the other hand…that’s more like it (including an under-penny further peek) for an electrical engineer like you and me.

Much of it is reminiscent of what we’ve seen before. Here’s the top-side view.

Once again, the relay is a Churod A16-V-105DA2F, although in comparison to its Tapo P125 cousin, it’s 90° rotated and downward shifted location-wise on the PCB this time.

Bottom side view next.

Now to the right.

And the left…wait, what’s this?

Silicon and broader software swaps

The Shanghai Belling BL0937 single-phase energy monitoring IC at right is the same as the one previously seen in the Kasa EP25. Below it is yet another five-lead SOT-packaged IC, presumably housing a dual-transistor combo and seen multiple times before, this time labeled as follows:

JWM3J
5G5hG

And in the middle is, once again, a switch alongside an LED. But check out the processor at left! In every other TP-Link smart plug I’ve taken apart so far, it has come from Realtek Semiconductor and is based on an Arm architecture. This time, in contrast, it’s the RISC-V-based Espressif Systems ESP8684.

The very first page of the datasheet clears up another discrepancy I’d noted; seemingly no discrete flash memory device anywhere on the mini-PCB this time. Instead, the documentation tipped me off that there’s “Optional 2 MB or 4 MB flash in the chip’s package”.

All of which leaves me with no shortage of questions, which do not include the contents of the as-usual difficult-to-access PCB underside (as usual, it’s quite bare, as far as I can tell, and FCC certification photos can fill any nagging knowledge gaps for the curious among you out there).

These questions include (but are not limited to) the following:

Previously, in transitioning from the conventional Tapo HS103 to the energy-monitoring Tapo EP25, TP-Link migrated from a single- to dual-core Realtek Arm-based chip. To what degree, if any, was a similar performance-boost need behind this more significant shift?
Were, as I alluded to at the beginning, product shortages or more definitive device phaseouts factors in this particular more significant change of supplier and architecture?
And to what degree, if any, was a desire to shift to a royalty-free, fully open-source processor architecture behind this design decision, keeping in mind the substantial software porting effort that would be required for TP-Link to actualize its aspiration?

I daresay I’m not likely to get any answers from TP-Link if I inquire, so I doubt I’ll even bother. Or from either Espressif Systems or Realtek, for that matter. But I’m guessing at least a one of you out there has a tangible clue as to what’s going on. Tips, either passed on to me anonymously over email or publicly in the comments, are greatly appreciated!

—Brian Dipert is the associate editor, as well as a contributing editor, at EDN.

Source link