You need a segger jlink programmer to use this, USB dfu does not come with the initial bootloader of isp, and nrf52832 has no USB connectivity. nRF52840-dk development kit can be used, and also can double as a dongle for the trackers.
Revision 3
E73-2G4M08S1C (nrf52840), icm42688 or compatible, mmc5983ma
https://oshwlab.com/sctanf/slimenrf3
Revision 2
isp1507-ax (nrf52832), icm42688 or compatible, mmc5983ma
- Uses nrf52832, no USB, SWD pins on dock connector instead
- No 0201 parts
- Removed onboard charger
- LED is brighter (sink instead of source)
- IMU is incorrectly wired
| pcb | 3d |
|---|---|
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| pcb before reflow | pcb with battery | tracker and case ( |
|---|---|---|
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Revision 2
icm42688 or compatible, mmc5983ma
- IMU is incorrectly wired
| pcb | 3d |
|---|---|
 |
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Revision 1
isp1807-lr (nrf52840), icm42688 or compatible, mmc5983ma
- USB untested
- 0201 components are hard to solder
- Charger is hard to solder
- LED with default resistor is too dim
| pcb | 3d |
|---|---|
 |
 |
| finished pcb | pcb with battery | completed tracker (case: |
|---|---|---|
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 |
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Revision 1
icm42688 or compatible, mmc5983ma
- 0201 components are hard to solder
| pcb | 3d |
|---|---|
 |
 |
dock test pcb
charging for 8 devices at 300mA, max power draw 2.4A
- Gets pretty hot if all 8 chargers are in use but it works fine
| pcb | 3d |
|---|---|
 |
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| completed charger pcb | charging dock ( |
|---|---|
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