Hi all,

Seemingly my schematic is done (PDF file below). I appreciate any point you mention to assure me it's all correct.

 

no headers? how is this supposed to interface to outside world?
no buttons or jumpers or dipswitches? how do you plan to controlling startup mode?
LEDs with 47 Ohm series resistors? that is asking for massive current from GPIO (25mA-ish).
several hundred of uF across battery?
5V zener across battery? how are you planning on charging the battery?

 

> no headers? how is this supposed to interface to outside world?
Connectors have headers to connect to

> no buttons or jumpers or dipswitches? how do you plan to controlling startup mode?
The device/board is not to be programmed often; mostly it's merely once
I changed my mind a little and connected both NRST and BOOT0 via a cap and resistor (respectively) to GND.

> LEDs with 47 Ohm series resistors? that is asking for massive current from GPIO (25mA-ish).
I'm going to use a LED Red 620-630nm 0805 25mA 60mW (XL-2012SURC) with a 68 Ω resistor for both LEDs in my design.

> 5V zener across battery?
yes, below is from the SIM's hardware design


> how are you planning on charging the battery?
The battery will be charged using a li-ion 18650 (with protection) module connected to it

 

Pardon me. I cannot see any USB connector in the PDF. How to program the board? Please correct me if I am missing something.

 

I saw at least two of them. Just drwn a bit different.