Pi-Toppping Raspberry Pi device accessories which enhance the Raspberry Pi.
Such as getting up Input format Analog, an H-bridge Output order to operate DC Motor / Servo Motor.
And other capabilities
Pi-Topping latest version is Pi-Topping 2.5B, which is the third generation of Pi-Topping all.
(Batch 1 Pi-Topping 1.0, version 2 Pi-Topping 2.0D, version 3 Pi-Topping 2.5B).
Fonte e mais detalhes aqui.