Hello all. I have been working for weeks on a large architectural lighting control system. I have finished the workbench portion of the system minus one piece. I decided to add Open/Closed circuit detection on the system. When a Light is on, a solenoid emits a 24vac signal out. I purchased enough HCPL3700 chips to finish the project. I cannot get these to do anything. I have also tried connecting a 0.2uF ceramic capacitor between pins 5 and 8 (I didn’t have a 0.1uf handy which the data called for) and removing it. The Most current i could every get out of Vo was somewhere around 0.4 Volts no matter what i did with the circuit. The Data sheet shows that Vo should be “HIGH” if the input current appears to be off. Even when I completely disconnect the input wires from pins 1 and 4 Vo never appears to go high. I have also tried 12vdc into the Vcc of the chip and the Vo results were the same.
If someone could help me understand what is going on, I would be grateful. I am at a loss.
Thank you in advance
This is the chip:
These are the data sheets that accompany this chip: