Path: ...!3.eu.feeder.erje.net!feeder.erje.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: piglet Newsgroups: sci.electronics.design Subject: Re: another fast one-shot Date: Fri, 14 Jun 2024 19:02:11 +0100 Organization: A Patent noisesome spinner Lines: 178 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Fri, 14 Jun 2024 20:02:12 +0200 (CEST) Injection-Info: dont-email.me; posting-host="e46204b4e6e19ff842968af5713a467c"; logging-data="3150824"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19CvCNgDFY9O8SfFV4X6cYv" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:ww+Y6hz4U7vFRlY0RaIHAXCFK+Q= Content-Language: en-US In-Reply-To: Bytes: 6498 On 13/06/2024 07:03, Bill Sloman wrote: > On 13/06/2024 4:11 am, john larkin wrote: >> On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom >> wrote: >> >>> On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote: >>> >>>> Here's another idea for a fast one-shot. This is the just-apply-money >>>> version and should get close to 1 ns pulse width and should easily >>>> trigger at 150 MHz. >>>> >>>> https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/ >>> Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1 >>>> >>>> I can use the other half of the dual comparator elsewhere. This one has >>>> programmable hysteresis too. >>> >>> Exposing my contemptworthy ignorance here no doubt, but what exactly >>> is it >>> that is fast about this design, John? And what would its application be? >> >> It would have a leading-edge prop delay of 350 ps, a minimum pulse >> width just over 1 ns, and would easily trigger at 150 MHz. Integrated >> one-shots, xxx123 types, are always terrible, even the obsolete ECL >> ones. >> >> It would be a programmable delay in a number of possible products, >> including some optical modulators. Just playing right now. >> >> More dollars could certainly do something faster, but as long as >> customers connect boxes with cables, faster isn't worth a lot. Light >> just moves too slow. >> >> Any suggestions for a faster one-shot? > > Version 4 > SHEET 1 2924 1040 > WIRE -592 -720 -768 -720 > WIRE 128 -720 -592 -720 > WIRE 304 -720 128 -720 > WIRE 768 -720 304 -720 > WIRE 976 -720 768 -720 > WIRE 1488 -576 1488 -720 > WIRE 128 -560 128 -720 > WIRE 304 -560 304 -720 > WIRE 768 -560 768 -720 > WIRE -592 -384 -592 -720 > WIRE 1072 -368 1072 -400 > WIRE 768 -320 768 -480 > WIRE 960 -320 768 -320 > WIRE 1008 -320 960 -320 > WIRE 128 -288 128 -480 > WIRE 176 -288 128 -288 > WIRE 576 -288 240 -288 > WIRE 768 -208 768 -320 > WIRE 304 -160 304 -480 > WIRE 400 -160 304 -160 > WIRE 576 -160 576 -288 > WIRE 576 -160 480 -160 > WIRE 640 -160 576 -160 > WIRE 704 -160 640 -160 > WIRE -768 -64 -768 -720 > WIRE 128 48 128 -288 > WIRE -272 96 -432 96 > WIRE 64 96 -192 96 > WIRE 640 128 640 -160 > WIRE 304 160 304 -160 > WIRE -432 240 -432 96 > WIRE -768 416 -768 16 > WIRE -768 416 -880 416 > WIRE -736 416 -768 416 > WIRE -592 416 -592 -320 > WIRE -592 416 -736 416 > WIRE -496 416 -592 416 > WIRE -432 416 -432 320 > WIRE -432 416 -496 416 > WIRE 640 416 640 208 > WIRE 640 416 -432 416 > WIRE 1072 416 640 416 > WIRE 128 464 128 144 > WIRE 768 464 768 -112 > WIRE 768 464 128 464 > WIRE -880 496 -880 416 > WIRE 768 496 768 464 > WIRE -736 640 -736 416 > WIRE -496 640 -496 416 > WIRE -736 656 -736 640 > WIRE -736 944 -736 720 > WIRE -496 944 -496 704 > WIRE -496 944 -736 944 > WIRE 304 944 304 240 > WIRE 304 944 -496 944 > WIRE 768 944 768 576 > WIRE 768 944 304 944 > WIRE 1760 944 768 944 > FLAG -880 496 0 > FLAG 960 -320 out > SYMBOL npn 64 48 R0 > SYMATTR InstName Q1 > SYMATTR Value BFR92A > SYMBOL npn 704 -208 R0 > SYMATTR InstName Q2 > SYMATTR Value BFR92A > SYMBOL voltage -768 -80 R0 > WINDOW 123 0 0 Left 0 > WINDOW 39 24 44 Left 2 > SYMATTR SpiceLine Rser=0.1 > SYMATTR InstName V1 > SYMATTR Value 5.0 > SYMBOL voltage -736 624 R0 > WINDOW 123 0 0 Left 0 > WINDOW 39 24 44 Left 2 > SYMATTR SpiceLine Rser=0.1 > SYMATTR InstName V2 > SYMATTR Value 4.5 > SYMBOL voltage -432 224 R0 > WINDOW 123 0 0 Left 0 > WINDOW 39 0 0 Left 0 > SYMATTR InstName V3 > SYMATTR Value PULSE(0 0.2 1n 300p 300p 100p 200n 2) > SYMBOL res -176 80 R90 > WINDOW 0 0 56 VBottom 2 > WINDOW 3 32 56 VTop 2 > SYMATTR InstName R1 > SYMATTR Value 22 > SYMBOL res 752 480 R0 > SYMATTR InstName R3 > SYMATTR Value 360 > SYMBOL res 112 -576 R0 > SYMATTR InstName R4 > SYMATTR Value 180 > SYMBOL res 624 112 R0 > SYMATTR InstName R5 > SYMATTR Value 43 > SYMBOL res 752 -576 R0 > SYMATTR InstName R6 > SYMATTR Value 180 > SYMBOL res 288 -576 R0 > SYMATTR InstName R2 > SYMATTR Value 1k > SYMBOL cap 240 -304 R90 > WINDOW 0 0 32 VBottom 2 > WINDOW 3 32 32 VTop 2 > SYMATTR InstName C1 > SYMATTR Value 3.3p > SYMBOL res 288 144 R0 > SYMATTR InstName R7 > SYMATTR Value 1k2 > SYMBOL res 496 -176 R90 > WINDOW 0 0 56 VBottom 2 > WINDOW 3 32 56 VTop 2 > SYMATTR InstName R13 > SYMATTR Value 43 > SYMBOL cap -608 -384 R0 > SYMATTR InstName C3 > SYMATTR Value 10n > SYMBOL cap -512 640 R0 > SYMATTR InstName C4 > SYMATTR Value 10n > TEXT -272 1000 Left 2 !.model BFR92A NPN(IS=0.1213E-15 VAF=30 BF=94.73 > IKF=0.46227  XTB=0 BR=10.729 CJC=946.47E-15 CJE=10.416E-15 TR=1.2744E-9 > TF=26.796E-12  ITF=0.0044601 VTF=0.32861  XTF=0.3817 RB=14.998 > RC=0.13793 RE=0.29088 Vceo=15 Icrating=4m mfg=Infineon) > TEXT -904 1024 Left 2 !.tran 0 500n 0 > > It's just a two transistor emitter-coupled monostable, but with the two > transistors as BFR92's run at 10mA,  it produces 1nsec pulse without fuss. > > Finding the broad-band PNPs to let you translate the output pulse to a > useful voltage level is tricky. Phil Hobbs has told us that there is a > least one still in production and available. > It is a pity it relies on an input pulse shorter than the output - at those speeds it would nicer to have a step input somehow? piglet ========== REMAINDER OF ARTICLE TRUNCATED ==========