is it possible optocoupler EL817 wiht input 3.3VDC and output 24VDC like below circuit. and if it possible what is the suitable value for the resistor

enter image description here

  • \$\begingroup\$ 1. EL817 output is not strong enough to directly drive a buzzer. The usual trick is to first drive a BJT which is strong enough to in turn to drive a relay switch (or a buzzer). You might like to skim the following post to get a rough idea on the EL817C/NPN BJT biasing design. 2. If you are going to use a BJT for EL817C, you might like to show your circuit so everybody can help. Cheers. Ref: electronics.stackexchange.com/questions/505318/…. \$\endgroup\$
    – tlfong01
    Aug 12, 2021 at 1:34
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    \$\begingroup\$ Why would a buzzer need opto-isolation and what current is this? \$\endgroup\$ Aug 12, 2021 at 1:53
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    \$\begingroup\$ please stop shouting. \$\endgroup\$
    – Hearth
    Aug 12, 2021 at 2:21
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    \$\begingroup\$ @tlfong01 okey i will upload full schematic after it finish. \$\endgroup\$ Aug 12, 2021 at 5:53
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    \$\begingroup\$ @TonyStewartEE75 in this case i want to switch on the buzzer by give 24VDC \$\endgroup\$ Aug 12, 2021 at 5:54


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