rusefi.com

Datasheet in Chinese, or Mandarin or what ever these scribbles are.
http://www.padauk.com.tw/upload/doc/PMS150C%20datasheet%20V004_EN_20180124.pdf

Purchased for $0.0353 in qty 10 from here.
https://lcsc.com/product-detail/PADAUK_PADAUK-Tech-PMS150C-U06_C168658.html

Also the 14 pin with 12x12bit ADC for $0.1691
https://lcsc.com/product-detail/PADAUK_PADAUK-Tech-PMS131_C114159.html

And the 16 pin with 10x12bit ADC for $0.1691
https://lcsc.com/product-detail/PADAUK_PADAUK-Tech-PMC232-S16A_C129130.html

Long winded review found here from Dave from EEVBlog.

I tried to buy from them but for 100 items which I needed they only had 40 in stock ...
maybe in the future will be better ...

Up to 5cents now. Limited peripherals and no analogue channels makes them less use than a lot of other 6-pin micros.

Analog out can usually be obtained via PWM followed by a low pass filter. Analog input can commonly be done with a similar approach, short a cap, then let if fill up. Measure the amount of time until you read a 1 instead of a 0. Granted those are crappy analog options. However a slow 8 bit analog option is acceptable for many applications.