BrailleNote Tieman Display

From Hackstrich

The Tieman braille display was the first model used in the BrailleNote notetakers. This display has reliability issues, and I'm reverse-engineering it to try to fix mine which is broken.

  • Display uses 1 "backplane board" per 8 cells
  • Each backplane board has 8 cell connectors, 2 inter-board connectors (left and right), and one Supertex HV507PG chip
    • The HV507PG is a high-voltage 64 channel shift register
  • Pinout of display connector (from edge of board opposite SMD cap)
    • Left Side (male)
      • Red - HV (~250VDC)
      • Grey - Ground
      • Grey - Data B
      • Grey - Straight through to right side
      • Green - CLK
      • Grey - !LatchEnable
      • Grey - LV (~5VDC)
      • Grey - Direction (Low = A in, B out)
    • Right Side (female)
      • Red - HV (~250VDC)
      • Grey - Ground
      • Grey - Data A
      • Grey - Straight through to left side
      • Green - CLK
      • Grey - !LatchEnable
      • Grey - LV (~5VDC)
      • Grey - Direction (Low = A in, B out)
    • Data pin is connected to straight-through pin on the last backplane board, which lets the BN read the bits back to ensure the display is working