ESP32 - microcontroller as the brains of the whole board. WiFi with PCB antenna, BLE, 4MB Flash, 8MB PSRAM, 240MHz. Driving the e-paper parallel lines directly.
*MCP23017 - I2C IO expander. Driving the misc (slower) e-paper lines and providing some extra GPIO pins.
*PCAL6416A - I2C IO expander. Replacement for MCP in newer Inkplates in time of chip shortage.
e-paper panel - depending on the specific Inkplate, the contents are shown on EPD. There’s a special connector for each of them. Some have a backlight and touchscreen and thus the additional circuitry for those.
CH340C - USB-UART adapter, paired with USB-C for programming and power.
*microSD card slot.
**TPS65186 - special EPD power management IC, providing specific voltages needed to drive EPD properly.
MCP73831 - lithium-ion battery charger. Linear and not so efficient one, but simple to use. Auto-select voltage source is on board as well.
22uA low-power thanks to low Iq voltage regulator from TI TPS7A2633.
*3 pieces touch pads based on TTP223.
Reset supervisor TPS3840PL27D takes care of proper reset at upload and manual reset.
*Pushbutton style power button thanks to MC14093BD logic gate and a single MOSFET.