Quote from: strip66 on June 08, 2018, 05:27:00 AM

Ledger Nano is a smartcard-based hardware wallet. A private key is created and signed offline in a smartcard secure environment.

The ledger nano (HW.1) was based on a smartcard (ST23YT66) with USB support.
However, it is not being maintained or (officially) sold anymore.

Their maintained product, the ledger nano s, is based on the ST31H320 Secure element, which does differ entirely from the HW.1 architecture.
This secure element doesn't even support USB/Displays. Thats the reason ledger uses a second microcontroller (STM32F042K6).
This was the attack surface used by Saleem Rashid when finding a vulnerability in their architecture.