Now that we have an idea of the mechanical form factor for the design and some of the large mechanical constraints, we are moving on to begin choosing the actual parts that will be on our board. This will involve things like the power regulation, level translators and other support devices. The first pass of any design involves some preliminary placement of components, but we will do the layout (and resulting “final placement” of components) in the next lesson.
Lesson Topics
- Implementing a simple 3V3 Buck Regulator
- Searching for the 3V8 Regulator
- Reviewing Block Diagram Inputs To 3V8 Regulator
- Comparing TI Battery Management ICs
- Choosing the battery management IC and looking at extra features
- Roughing in the battery management solution
- Finding the battery management inductor
- Pulling in the SIM card holder and daughtercard connector
- Battery management schematic cleanup and board reorg
- Adding a logic level translator and JTAG header
- Modifying uFL positions and adding 2.4GHz chip antenna
- Simplifying the main board block diagram
- Flipping the script (components)
- Adding a serial switch (mux) for changing control between the BLE and CELL modules
- Switching to a 50 pin daughtercard header
- Simplifying UART comms and adding a new interface to the modem
- BOM cleanup and price estimation
- Adding support components to the schematic for the nRF52
- Adding support components for the BG95/EG91
- Cleanup of power input
- Cleanup of connections