> Searching does not turn up any references to LRVALT1G, is that the real > number? > > > LRVALT1G =3D TLV431 =3D $US0.035 / 10000 China. > > 20c to $1 /1 in US. > Doh. Well held Sir. I'd have thought that that number would be burned into my brain by now - even if/when my fingers tried to typo it. TLV431 =3D =3D LR432ALT1G Here is a data sheet from the manufacturer's website http://www.lrc.cn/data/pdf/lr432alt1g.pdf LRC is or was a cooperative venture between Leshan Radio and ON Semi. I think On Semi owned about 30%. Don't know current status. BUT They have a number of trailing edge parts that are a very very very close match to older ON Semi parts and at very very good prices compared top western badged parts. eg LBC808 / 817 =3D =3D BC807/817. About 1 cent in 1k up quantity. The LR432 =3D TLV431 =3D 1.24V ref version of usual TL431 has several super= ior specs to parts from almost any other maker.* Whether all are real I have never checked. One day. I use them conservatively and they have served well. * eg they have a 100 ma max Isink rating (watch dissipation) which is the same as many (but not all) TL431 BUT a;most all other TLV431 have much lower Isink max. The main feature of a TLV431 compared to a TL431 aparet from the 1.24 versus 2.5V reference is that the TL431 needs about 500 uA Cathode current to come into regulation whereas a typical TLV431 or LR432ALT1G is under 100 uA worst case. Actual fugure varies somewhat with manufacturer but LR432ALT1G says 80 uA max and 60 uA typical. This is the main limiting factor in how low a qiescent current you can draw while maintaining regulation, so if you are using them to DIY your own regulator a TLV parts allows about 5x lower Iq in many cases than 1 TL part. With care you can build a MOSFET based voltage regulator with an in regulation quiescent current of about 100 uA at almost any power level by using a MOSFET as a pass element.f ________ (ALT1G is the 1% version in 3,000 tape and reel. . .... ALT3G is 10,000 tape and reel. .. Quote the ALT1G and everyone supplies either to suit. Identical parts. They do a 0.5% version too. See eg prices shown are rubbish as ever: http://www.alibaba.com/showroom/lr432alt1g.html http://www.alibaba.com/showroom/nova-tl432%252flr432alt1g.html I've been quote 3.5 cents US by several companies in the past 2 weeks in 3000 and 10000 quantity (doesn't seem to make much difference.) Also 4 cents, 5 cents and 23 cents Note that there are two pinouts for the TLV431 part in SOT23 pkg. I have had major aggro from two unrelated manufacturers getting this wrong - even when I noted it specifically with diagrams and warnings in the second case. They then altered the PCB copper for one of the two parts affected and not the other. LR432... and some TLV431 or T:V432 or TL432 or TL431 or ... use Ref - Anode - Cathode where a MOSFET's std gate-drain-source connections would be. Others (less common) swap A and K. They work 'poorly' with A & K reversed :-(. Russell Had to most urgently rush off - sending this not sanity checked. No doubt Bob will point out any areas where I fail to meet muster :-). .. --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .