Eval¶

Hardware¶

Display: WSH-12561; 37,32x31,8; 200x200Pixel; eval board funktioniert
Akku: 31063 (Garmin Fenix 3) 300mAh; 300 mAh; 31,6 x 24,8 x 4,3

MCU¶

Pixel-data is 5KB ((200*200)/8); need bigger MCU; but the STM32L433CCU6 i have is too much

STM32L433CCU6: Too much
STM32L151C6U6A waers eigentlich. USB, 128KB Flash, 32KB SRAM, EEPROM 32KB Flash, 10KB RAM, hat USB
STM32L051C8T6; no USB
STM32L053C8T6; 11,60Euro, whatt?

STM32L151C6U6A hab ich schon hier. STM32L151CB gibts auch noch, wenn auch teure 12.15Euro.
Check the binary size. Along with USB.

• Fonts, USB, Terminal, Debug, LUT: 29616
• Fonts, USB, Terminal, RelWIthDebug, LUT: 22884

Alphabet: 22 Zeichen * 8 Bytes= 176 Bytes. Display-Content 5000 Bytes.
32KByte koennten reichen. Versions on Display optional.
4KByte EEPROM fuer Settings.

Power¶

Lade-Chip: https://www.mouser.de/datasheet/2/268/MCP73871_Data_Sheet_DS20002090F-2932254.pdf
VCI wants 3V3. VDDIO may be less but is not specified. Reference schematics connects VDDIO directly to VCI.
Start with 3V3.

"ad_mcp73871" is getting manufactured. Lets see how it behaves on V_OUT.

Open points¶

MCU: 1.65 V to 3.6 V power supply, would need LDO. Would need this self-holding-mosfet chain. Would need seperate battery for RTC. MCU has not VBAT.