Surprise Delivery: Maxim Integrated/ADI MAX32666FTHR Application Platform Unboxing

12 Nov 2022

Surprise Delivery: Maxim Integrated/ADI MAX32666FTHR Application Platform Unboxing

It's been a busy time for me recently - aside from the busyness of work that never seems to abate with the slow transition back to "work-from-work" which now involves teaching course co-ordination duties, I've also been finalising my contributions to a design challenge and a RoadTest while running some experiments behind-the-scenes. But nevertheless, it seems element14 continues to deliver the goods, so to speak.

It was back in August when the I/O Link Quiz giveaway was decided upon, and I was one of the lucky five to receive a Maxim Integrated (now, Analog Devices Incorporated (ADI)) MAX32666FTHR Application Platform development kit. While I was told about this and graciously accepted, element14 went silent on me for a while. It was only upon me following up about the prize did they realise that it got shipped to the wrong branch (oops!) and they'd have it sent to me as soon as they managed to get it (thanks dychen).

It was late October when this box arrived for me ...

... and it was no ordinary box, having this torn error label being stuck to the side. I had to have a chuckle.

Nestled inside, under some scrunched up paper packing was the kit.

This one seems to have come out of element14/Farnell's own stock - Order code 3528669 if anyone is interested, currently listed for AU$56.07 on my local element14 branch.

The goodies are kept under some pink plastic foam sheeting ...

... and was more than I expected. It consists of the MAX32666FTHR board which has an Adafruit Feather-compatible form factor, a pair of terminal headers, a USB A to microB cable and a box containing a MAX32625PICO kit acting as the DAPLink Debugger.

What has this got to do with IO-Link, you may ask? I had the same question myself, as this seems to be a rather powerful dual-core ARM Cortex-M4 with FPU solution clocked at 96MHz with Bluetooth 5.0 connectivity ideal for wearable devices. Not much to do with IO-Link, aside from the fact that both are solutions that Maxim Integrated (now ADI) make, but perhaps this could be useful for running more sophisticated sensor/controller payloads. Of interest is that the MAX32666 is also listed on the Maxim site as being somewhat suitable for Bluetooth LE Audio - something that Nordic Semiconductor have been quite active about recently on element14 with their nRF5340 which is a slightly less powerful dual-core ARM Cortex-M33 at 128MHz/64MHz + Bluetooth 5.2 solution.

The pin headers were sort of interesting - gold plated contacts with silvery-tinned legs for the PCB.

The supplied USB cable seems to be very ordinary one ... thin 28AWG wires, probably not ideal for charging a cell-phone but fine for a low-powered development board.

The board itself is surprisingly well packed - not only do you get the powerful SoC with Bluetooth radio and supporting antenna, the is also an RGB LED, battery charger and accelerometer on-board.

They even made space on the underside for a microSD card, which is nice, but it does get close to the Bluetooth antenna so there may be some effect on transmission from having a card installed. One of the key benefits of the MAX32666 seems to be the fact that it also has an SD 3.0-compatible interface - which should mean no more slow and awkward SPI interfacing with cards which could result in compatibility and performance issues.

As mentioned earlier, the "mint-tin" doesn't actually contain any mints. It's got the Maxim Integrated logo printed on it - it's just a shame that mine was somewhat scratched up even before I received it.

Inside is a MAXDAP DAPLink compatible debugger which is required to program and debug the board. I suppose it is nice to have this included, but it is also likely because the MAX32666 doesn't have a bootloader-method of flashing the device.

While it is a debugger, it is actually also a development board of its own (and a rather cute one at that) using the MAX32625 which is also a 96MHz ARM Cortex-M4 with DSP.

It includes the MAX32625PICOBD, a 10-pin debug cable and a USB-A to microB cable as well - this one unmarked.

This board is absolutely tiny - can you believe a 96MHz Cortex-M4 lives here, alongside power management ...

It's not like they cheated and stuffed things onto the back - as there's absolutely nothing but pads and traces. It's so small that the silkscreen is starting to lose its definition.

The ten-pin debug lead is a bit thin and fragile, so some care is necessary when handling it. Make sure that the red stripe is aligned to Pin 1 for proper operation!

Here is a close-up of the USB-A to microB cable - this one is from a different vendor to the other cable. It's nice the cables are included, as sometimes these can be getting harder to find now that USB-C has gained significant momentum.

Overall, I'd have to say that the chips do offer a lot of promise based on the specifications - although the chips themselves are not exactly cheap, which is to be expected. You may be wondering why I did only an unboxing - the reason is simply because I realise that I simply do not have enough time to do anything more with this board. As great as it is, it turns out that its arrival coincided with an actual need to evaluate capable BLE 5.x-based SoCs for wearable devices at my place of work. Rather than try to learn all the ins-and-outs of BLE, I decided to gift this set to my colleague who is more closely related to the project and has the necessary experience to make the most of it. Being related to an actual product in development means that I won't get to report on much - but I hope that this is a good fit, as we were looking at a number of options including the Nordic nRF5340, alongside alternatives from Infineon and Silicon Labs.

Thanks element14 and Maxim Integrated/Analog Devices Inc. for this gift - while I won't be able to blog about it any further, I hope that by passing it on, that it sees more use than it would in my time-restricted hands and is appreciated for its timely appearance.