Hi everyone, I need to replace a TLP504A 8-pin phototransistor that is no longer in production. Can you help me find an equivalent? Thanks.
Here’s a simpler comparison + a substitute recommendation for the TLP504A. I also noticed a useful project that uses something similar — maybe that helps you confirm form-factor or wiring: Arduino Photogate PCB on PCBWay.
TLP504A is a phototransistor optocoupler (LED input → transistor output), typically in an 8-pin DIP for the 2-channel version, or 16-pin for the 4-channel version (TLP504A-2).
Key specs: collector-emitter voltage ~ 55 V, isolation voltage ~ 2500 Vrms, CTR (current transfer ratio) of at least ~ 50% under certain test conditions.
The PS2505-2 is a strong candidate. Some highlights:
V_CE up to ~ 80 V, high isolation (5000 Vrms in some specs) which gives a margin over the 55 V of TLP504A.
Similar switching speeds, and current transfer ratios in the same ballpark.
Pin-package may differ (depending on channel count), so check if your PCB matches or if you’ll need minor wiring change.
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thank you, you were very kind
Unfortunately it is not available on the DigiKey website
Hello @andreug1
The closest part I found that is an active part on our website to TLP504A Phototransistor is part number TLP621-2XGB Isocom Components 2004 LTD | Isolators | DigiKey