Path: ...!weretis.net!feeder9.news.weretis.net!feeder8.news.weretis.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Phil Hobbs Newsgroups: sci.electronics.design Subject: Re: Fast monostable with a transistpor array Date: Sat, 15 Jun 2024 16:03:21 -0000 (UTC) Organization: A noiseless patient Spider Lines: 105 Message-ID: References: <8epo6jhf5k5nbkkqp5ot9b6nq1lhoia870@4ax.com> <666ca9ad$0$2363142$882e4bbb@reader.netnews.com> <666d1cc3$0$2363142$882e4bbb@reader.netnews.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Sat, 15 Jun 2024 18:03:21 +0200 (CEST) Injection-Info: dont-email.me; posting-host="b6306807801197aca634f3e7758baf06"; logging-data="3723689"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19/1RciFaQHeiJzRi7a4zxM" User-Agent: NewsTap/5.5 (iPhone/iPod Touch) Cancel-Lock: sha1:IAOja3MVgWnlciCdPD7LdhBoSWg= sha1:bMnbpS3cVLdCXMUI1nw06ZUbeSE= Bytes: 5636 john larkin wrote: > On Sat, 15 Jun 2024 00:47:00 -0400, bitrex wrote: > >> On 6/14/2024 7:10 PM, john larkin wrote: >>> On Fri, 14 Jun 2024 16:35:59 -0400, bitrex wrote: >>> >>>> On 6/14/2024 12:33 PM, john larkin wrote: >>>>> On Fri, 14 Jun 2024 12:18:23 -0400, "Edward Rawde" >>>>> wrote: >>>>> >>>>>> "john larkin" wrote in message >>>>>> news:8epo6jhf5k5nbkkqp5ot9b6nq1lhoia870@4ax.com... >>>>>>> On Fri, 14 Jun 2024 11:08:56 -0400, "Edward Rawde" >>>>>>> wrote: >>>>>>> >>>>>>>> >>>>>>>> "john larkin" wrote in message >>>>>>>> news:hilo6j9dgctalpiu4v09rpdavf6fetm1cv@4ax.com... >>>>>>>>> On Thu, 13 Jun 2024 23:25:37 -0400, "Edward Rawde" >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> "Bill Sloman" wrote in message >>>>>>>>>> news:v4f2nm$2augj$1@dont-email.me... >>>>>>>>>>> One option John Larjkin doesn't seem to have explored is using >>>>>>>>>>> Renesas HFA3096 five transistor array as basis for his >>>>>>>>>>> mononstable >>>>>>>>>>> and level shifter. >>>>>>>>>>> >>>>>>>>>>> It offers three 8GHz NPN parts and two 5.5GHz PNP parts in a single array. >>>>>>>>>>> >>>>>>>>>>> https://www.renesas.com/us/en/document/dst/hfa3046-hfa3096-hfa3127-hfa3128-datasheet?r=494216 >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> I put the NPN model parameters into a circuit designed by yourself. >>>>>>>>>> It's late now but I got as far as Time step too small. >>>>>>>>>> >>>>>>>>> >>>>>>>>> That is neither fast nor a monostable. >>>>>>>> >>>>>>>> Yes ok it's an astable and certainly not intended to be fast. >>>>>>>> It was intended only to see if the model worked. Nothing more. >>>>>>> >>>>>>> It doesn't work! >>>>>>> >>>>>>>> >>>>>>>>> >>>>>>>>> There's no reason to use many-GHz parts in micropower circuits. One >>>>>>>>> reason is that the sim breaks. >>>>>>> >>>>>>> Most versions of the HFA3046 are obsolete. The only one left at >>>>>>> Digikey costs $12. It would be risky to design around that part. >>>>>> >>>>>> If it's obsolete or going obsolete then yes it would make no sense to use it. >>>>>> I would guess that you get to do plenty of work because a >>>>>> manufacturer has suddenly decided to discontinue a part. >>>>>> >>>>>>> Wasn't HFA originally a Harris part? >>>>>>> >>>>>>> There are lots of dual (non-monolithic) diodes and bipolars and fets >>>>>>> around, but the monolithic arrays are mostly gone. >>>>>> >>>>>> What part would you recommend (single or dual) and does it have a >>>>>> working LTSpice model? >>>>> >>>>> Just pull up some parts from the standard library, some low current >>>>> NPNs like BC547 maybe. Look for low capacitances if you care about >>>>> that; the HFAs are good in that respect. >>>>> >>>>> Why do people avoid making clean 4-wire connections on schematics? >>>> >>>> There's this new trend of breaking the circuit schematic up into little >>>> boxes like this, it's nuts: >>>> >>>> >>>> >>>> >>> >>> That's criminal. >>> >> >> Combining schematics and documentation in the same document is sort of >> like a toothpaste and orange juice smoothie. I like orange juice, and >> toothpaste is useful. However... > > We keep a separate design notes folder. It can say a lot more than > could be hacked onto a schematic. I don't like a lot of comments on my > schematics. > > I often annotate schematics with things like nominal voltages, dashed rectangles to indicate circuit groups, and anything unusual that might be mistaken for an error, such as a BJT used upside-down. Makes it easier for others to understand. (We also keep notes, markups from bringup, and so on. ) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics