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I'm thinking about driving EL wire as if it were a ws2811 LED for convenience of integration with actual ws2811 LED strips. The idea is that the WS2811 Red channel acts as the enable/control input for a EL wire driver IC. I'd like to drive ~1M of common EL wire.

I've followed the example schematics in the ws2811 and HV850 datasheets, with the only modification being lowering the resistance from 1500 ohms to 500 ohms to triple the frequency, which I've heard will let me drive more wire more smoothly at the cost of brightness/lifetime.

Does this circuit look correct? Will it work? Are there any gotchas I am missing?

enter image description here

Sources:

https://learnitstepbystep.blogspot.com/2020/10/creating-pixel-led-using-ws2811-ic.html https://www.digikey.com/en/products/detail/microchip-technology/HV850MG-G/4902788

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The Logic levels are fine for connecting the WS2811 to the enable line of the HV280, and the enable line can use PWM. The problem might bein timing as the WS8211 does its PWM switching the kHz range and the HV280 needs to have its switching lower than the EL switching frequency 250 to 338Hz

EL lamp dimming can be achieved by applying a PWM signal to the ENABLE pin. The PWM signal duty cycle is proportional to the lamp brightness. This is done by pulse skipping the output pulses. The PWM frequency should be kept below the EL frequency but above 50Hz to avoid flickering.
Source: https://ww1.microchip.com/downloads/en/DeviceDoc/hv850.pdf

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  • \$\begingroup\$ Perhaps I can just up the EL frequency? I was aiming for 750Hz. Alternatively, I could try to down-shift the PWM frequency, but I want to avoid making my PCB larger or more work to assemble, so I want minimal components. Any suggestions? \$\endgroup\$ Apr 12 at 18:11

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