Notes on electronics for SKEDI (Saxophone/Keyboard? Electronic Digital Instrument).

LED eval board:

Display ideas:

  • QBASS40YG0 (1516-1020-1-ND) Brightek 14-seg 0.4" SMT common Anode (Mike bought a bunch of these)
  • 160-1982-5-ND Lite-on two-digit 14 segment LED with serial interface

Back to smaller 14-segment displays with no decoding. Decoder chip candidates:

  • ATMega168 $4.50
  • ATMega88 $1.63
    • Direct drive: need 1 uC per digit and maybe resistors
    • Mux drive: need fancy software
    • Shift-register drive (with blanking/disable for update). See e.g. 74LS673. Would need blanking transistor on Anode and probably series resistors on all cathodes.
  • LED1642WTTR $2.50 - drives 16 LEDs, shift register, SSOP-24 (no thermal pad)
  • MAX6955 - Drives up to (8) 14 seg digits. I2C interface. 36-SSOP
    • $22 each but run 4 displays

Other candidates:

  • IS32FL3238 $2.35 - drives 18 LEDs, I2C, eTSSOP-28 (thermal pad)
  • IS31FL3726A
  • TLC5940 $3.87 - 16 output (eVOLVER PWM). 28HTSSOP (thermal pad)

Slave AVR uC ideas:

  • ATTiny841: SO-14, ADCs, USART, 8k bytes flash, 512b RAM, ADCs
  • ATTiny85: SO-8, ADCs, 8k bytes flash, 512 bytes RAM (ATTINY85-20SU-ND)
Last modified 12 months ago Last modified on Feb 28, 2023, 9:27:30 AM