Alternatives to H21LOB?
fairchild has ended the manufacturing of the H21LOB component. Some sellers are already out of this component, others should be getting harder and harder to get it (read it will likely get more expensive). so far makerbot has more to sell Are there other components that would fit this circuit board as it is? Are there other components that have the same specs, but another footprint (where "only" the holes on the board would need to be moved)? --F15ijp 17:18, 11 August 2010 (UTC)
- Omron EE-SX498 looks like it has the same electrical specs, but another footprint - second opinion needed though! --F15ijp 17:18, 11 August 2010 (UTC)
- Vishay TCST2103 is used in the kit from reprapsource. The footprint looks different in the data sheet though - second opinion needed though! --F15ijp 08:37, 22 August 2010 (UTC)
- For a design using the Vishay optical interrupters (TCST1103, TCST2103, TCST4103, ...), see Gen7_Endstop_1.3.1. --Traumflug 11:42, 20 October 2011 (UTC)
makerbot.com now wants $4.80 each for H21LOB in quantity 5 where a month ago they wanted $0.95. The price increase has started. F15ijp is now a proven Prophet. Maybe he'll give me a stock tip or two.
My reading of the Omron EE-SX498 ($2 at Mouser) says it IS a good replacement, including a 4.5V-16V supply voltage and hysteresis to prevent bounce, both like the H21LOB. What I haven't figured out is IF the correspondence is between the H21LOB and the EE-SX498 and also between the H21LOI and the EE-SX398 OR is it the other way around? Each is the inverse of the other. One spec sheet says:Dark ON model (EE-SX398) and Light ON model (EE-SX498). The other has an "Input Output Table" that says:Led=On Output=High and LED=Off Output=Low. Which way do they match?
It isn't drastically important, since our software can work either way. I'm ordering six EE-SX498 for my build and I'll soon know for SURE.
The Vishay TCST2103 datasheet says nothing about hysteresis. It's probably better than the mechanical endstops so MANY people are using, but I've read about bounce problems in the forum so I'd rather not test it to save a few cents. --Jed 23:33, 19 October 2011 (UTC)