Board Revisions
This is the very first prototype.
Some notable features:
- No 74HC595 output enable pullup. This makes it quite unsafe for use.
- Configuration DIP Switch 4 unusable as it is connected to the Arduino nano LED pin
- Only one row and one column output connector
- Added 74HC595 output enable pullups
- Added all output connectors
SMD version by Marcus.
SMD version. Some changes over last revision:
- Added column output 10k pulldown resistors
- Added 4.7V Zener diodes to column input as overvoltage protection
- Removed the 560Ohm MOSFET gate resistors - the UL2803 should easily be able to drive the gate
- Added a 0.2Ohm current measurement resistor to GND line
- Moved DIP switch to D8-D11 so that all switches can be used and the LED of the Arduino nano is kept free
- Removed the status LED, use the Arduino LED instead
+18V from columns
This version is the same as v1.3 with one new feature:
- There are new Schottky diodes on the board which allow for using the +18V from the columns connector (J138 IN) directly. When powering the board like this only the ground pin (- pin on the +/-18V connector) needs to be connected to the power driver board.
Notice that this board is slightly wider than version 1.3.
This version is the same as v1.4 but in a single sided layout for easier production. The 0.2 Ohm current measurement resistor to GND line has been removed again.
This is a complete overhaul of the afterglow board.
Changes compared to previous boards include:
- Support for WPC, Data East, System 11 and Whitestar/S.A.M. with one single board
- RP2040 microprocessor, allowing for higher resolution PWM
- Completely new firmware, see here
- Row input isolation using optocouplers, reducing the risk of damaging the board when no ground is connected
- Support for hats, e.g. for connectivity, debugging or modding
- Optimized for easy and cheap production
