MEGAphone Fabrication of the first module PCBs

I've been busy working on the schematic and PCB design for a bunch of the modules for the MEGAphone lately.  The first batch of those I had sent off for fabrication by PCBWay, and they have finally arrived. So let's have a look at what we have:

Well, that's a bit hard to see what's going on, so let's look at each in turn. My lighting here isn't that great right now, but it should be enough that we can identify each PCB from it's packing label.

First we have the audio jack PCB:

Then the high-efficiency DC:DC converter:

The Audio Codec board:

SIM and SD-Card carrier:

Cellular modem carrier:

MPPT Battery Charger board:

Low-current DC:DC converter module:

And finally, the MEMS microphone carrier board.

 So let's look at where this gets us to in terms of the milestones:

Milestone 2.1.2 High-efficiency DC-DC converter module to power the various sub-systems: Schematic -- done -- see https://c65gs.blogspot.com/2025/02/megaphone-2a-dcdc-converter-module.html and https://github.com/MEGA65/megaphone-modular/tree/main/modules/high-efficiency_dc-dc_converter

Milestone 2.1.3 High-efficiency DC-DC converter module to power the various sub-systems: PCB Layout -- done -- see https://c65gs.blogspot.com/2025/02/megaphone-2a-dcdc-converter-module.html and https://github.com/MEGA65/megaphone-modular/tree/main/modules/high-efficiency_dc-dc_converter

Milestone 2.1.4 High-efficiency DC-DC converter module to power the various sub-systems: PCB Fabrication -- done -- see the photos above.

Milestone 2.3.2 Battery management and energy harvesting module to allow USB-C, integrated solar and external 12/24V vehicle battery power sources, and efficient management of the integrated rechareable battery: Schematic -- done -- see https://c65gs.blogspot.com/2025/03/megaphone-battery-management-and-energy.html, https://github.com/MEGA65/megaphone-modular/tree/main/modules/battery-connector, https://github.com/MEGA65/megaphone-modular/tree/main/modules/input-power-selector, https://github.com/MEGA65/megaphone-modular/tree/main/modules/usb-c-power-in, https://github.com/MEGA65/megaphone-modular/tree/main/modules/solar-and-dc-connectors, and https://github.com/gardners/mppt-charge-controller/tree/8d80fb90b56f2cbbb3eda396a8fb4dab4cb2aabd

Milestone 2.3.3 Battery management and energy harvesting module to allow USB-C, integrated solar and external 12/24V vehicle battery power sources, and efficient management of the integrated rechareable battery: PCB Layout -- done -- see https://c65gs.blogspot.com/2025/03/megaphone-battery-management-and-energy.html, https://github.com/MEGA65/megaphone-modular/tree/main/modules/battery-connector, https://github.com/MEGA65/megaphone-modular/tree/main/modules/input-power-selector, https://github.com/MEGA65/megaphone-modular/tree/main/modules/usb-c-power-in, https://github.com/MEGA65/megaphone-modular/tree/main/modules/solar-and-dc-connectors, and https://github.com/gardners/mppt-charge-controller/tree/8d80fb90b56f2cbbb3eda396a8fb4dab4cb2aabd

Milestone 2.3.4 Battery management and energy harvesting module to allow USB-C, integrated solar and external 12/24V vehicle battery power sources, and efficient management of the integrated rechareable battery: Fabrication -- done -- see photos above

Milestone 2.4.2 Cellular modem communications module, including SIM card module: Schematic -- done -- see https://c65gs.blogspot.com/2025/02/megaphone-sim-card-sd-card-module.html, https://c65gs.blogspot.com/2025/02/megaphone-cellular-modem-module.html, https://github.com/MEGA65/megaphone-modular/tree/main/modules/cellular-modem, https://github.com/MEGA65/megaphone-modular/tree/main/modules/sim-and-sd-card

Milestone 2.4.3 Cellular modem communications module, including SIM card module: PCB Layout -- done -- see https://c65gs.blogspot.com/2025/02/megaphone-sim-card-sd-card-module.html, https://c65gs.blogspot.com/2025/02/megaphone-cellular-modem-module.html, https://github.com/MEGA65/megaphone-modular/tree/main/modules/cellular-modem, https://github.com/MEGA65/megaphone-modular/tree/main/modules/sim-and-sd-card

Milestone 2.4.4 Cellular modem communications module, including SIM card module: Fabrication -- done -- see photos above

Milestone 2.5.2 Internal microphone and speaker module: Schematics -- done -- see https://c65gs.blogspot.com/2025/02/megaphone-mems-microphone-module.html, https://c65gs.blogspot.com/2025/02/megaphone-audio-codec-speaker-driver.html, https://github.com/MEGA65/megaphone-modular/tree/main/modules/mems-microphone, https://github.com/MEGA65/megaphone-modular/tree/main/modules/audio-codec

Milestone 2.5.3 Internal microphone and speaker module: PCB Layout -- done -- see https://c65gs.blogspot.com/2025/02/megaphone-mems-microphone-module.html, https://c65gs.blogspot.com/2025/02/megaphone-audio-codec-speaker-driver.html, https://github.com/MEGA65/megaphone-modular/tree/main/modules/mems-microphone, https://github.com/MEGA65/megaphone-modular/tree/main/modules/audio-codec

Milestone 2.5.4 Internal microphone and speaker module: Fabrication -- done -- see photos above

Let's see how this looks on the block-diagram, to get a sense of the overall progress represented by this work:

Not bad -- and as we can see, some of these modules are reused in multiple places, so we have knocked off most of the orange boxes, too.

The main difference between what was planned and how I have progressed is that I've tended to further break down some of the modules, to make their designs simpler.

From here, I'll decide whether the next step is to assemble these modules, or whether I'll do the PCB design for more of the remaining modules on the schedule. Probably a mix of the two.  Certainly I can prepare the bill of materials for each of the modules I've already designed, and order those parts ready for assembly, since they will take a week or so to arrive, in any case.