I have some 7 segment Panaplex displays (SP-101) which I have a typical Cathode Current of 700uA for each of the large segments (7 per display).
If I wanted to deliver the 170V HV supply via PWM so that I could vary the brightness / duty cycle then would I be at liberty to drive all 6 displays via a single EL-817 (or equivalent) Opto Isolator? My maths suggests that with all seven segments of all six displays illuminated that's 7 x 6 x 700uA = 42 x 0.7mA = 29.4mA. >From the specification of an EL-817 I note that the Collector current is rated at 50mA. Does that suggest that I could be OK displaying 888888 and using a single EL-817 I could dim the display? I should point out that my goal is not to actually dim the display at all really, I just wanted to reduce the duty cycle as far as I reasonably could in order to promote the life of the displays. I noted that when I ran them continuously they actually got slightly warm - which I assumed was not ideal. I am currently (!) using 68K Anode resistors with an HV supply of 170V. The displays have an Anode to Cathode voltage drop of 135V so I would expect (though have not measured) to cathode current to be something like: =(170-135)/68K =35/68K =514 microAmps Does this make any sense? ... and if so, would driving the Anode HV via an EL-817 be a good plan? Thank you for listening Richard -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/1f506f4a-ea40-4708-8e74-dd2dd03ab857%40googlegroups.com.
