Custom teensy 3.2

[Sean Dimmock]

I have little experience with designing my own pcb's and so thought it would be good to get started by using the components and community support of the teensy. I have wired up the mk20 and linked the picture as I would greatly appreciate if anyone can give me general support for my projects.
FYI; I haven't connected a USB yet but I have the resistors and pinout at the bottom. I am using the NCP551SN50T1G‎ voltage regulator for the battery input and the PMEG4010CPA,115‎ diode to connect both inputs to the chip, both found on digikey. Also I know I need a switch on pin 10 of the mkl02.
Any feedback would be greatly appreciated, be as harsh as you like since I am very much new to this and am eager to learn.

Questions of interest:
Do you think this design is correct?
Are the labelled pwm pins definitely all pwm?
Have I correctly connected the sda and scl pins?
Pin 50, why is it for both sck and LED? Can't you use both?

Also any information on placing and routing these components on the board would be brilliant.
Sorry for any inconvenience, I am new to this forum so let me know if this post is inappropriate or in the wrong forum etc.
Thanks in advance,
Sean

[PaulStoffregen]

The VBAT pin on MK20 needs to be connected to 3.3V. That's one of the common issue mentioned on the MKL02 page (scroll down to "Troubleshooting")

https://www.pjrc.com/store/ic_mkl02.html

[jonr]

I'd compare schematic/parts/layout to some of the publicly available designs. For example, https://gitlab.com/our-sci/reflectance-spec-PCB.

[mstiller]

Shouldn't the crystals have some load capacitors nearby?