Use at your own risk. This is an experimental project. Rev. 7 has been hardware-verified to work, but requires a bodge wire fix.
Important
View Rev. 7 Bodge Wire Photo
This repository provides Gerber files for an internal MicroSD card reader daughterboard designed for the ThinkPad T14 (Gen 3 / 21CG). It replaces the stock right-side single USB daughterboard.
- Controller: Genesys Logic GL823K (USB 2.0 MicroSD Card Reader Controller).
- ESD Protection: USBLC6-2SC6 monolithic ESD protection array.
- Data Integrity: Ultra-low line capacitance (1 pF) prevents signal degradation on USB 2.0 differential pairs (D+/D-).
- Line Coverage: Dedicated ESD clamping for data, clock, and command lines.
- Rail-to-Rail Clamping: Suppresses high-voltage electrostatic discharge before transients reach the controller or internal hub.
- Interface: 20-pin FPC / board-to-board connector (
CON1). - PCB Thickness: Recommended 1.0 mm for proper chassis clearance and alignment.
Note
Rev.8 integrates the missing trace fix from Rev. 7 (eliminating the need for a jumper wire) and adds additional decoupling capacitors for power rail stability.
- Chassis Modification: Physical filing or trimming of the laptop's plastic/magnesium subframe should not be required.
- Connector Orientation: Ensure Pin 1 on the daughterboard aligns with Pin 1 on the motherboard connector before applying power.