This is a status panel driver circuit. This circuit is used to turn on lamps or LEDs in a graphic panel that represent faults, action, and status of an industrial machine. This circuit has advantages compared with other graphic status panel. It is more economical than computer graphic display and the communication between machine status and operator faster than other types of indicator. Here is the circuit :
To turn on lamps or LEDs, this circuit uses two TPIC6C596 power shift registers are arranged in a cascade. While clocking the shift register clock (SRCK), the machine controller outputs the status word to the serial input (SER IN). The data transferred to the storage register after the 16th clock by the register clock (RCK). When the output enable is low, the lamps are turn on corresponding to status word with ones being on and zeros off.
If we require more lamps, we just cascade additional shift register while maintaining the same three input control signals. [Source: Texas Instruments Application Note]
