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My first tape-outs
3 days ago • 0 commentsThis week I have had the chance to submit 8 designs to TinyTapeout ! Actually, 4 designs adapted to 2 nodes:
SG13G2:
https://app.tinytapeout.com/projects/3747 : https://github.com/ygdes/ttihp-HDSISO8
https://app.tinytapeout.com/projects/3758 : https://github.com/YannGuidon/miniMAC_tx
https://app.tinytapeout.com/projects/4039 : https://github.com/ygdes/ttihp-HDSISO8RS
https://app.tinytapeout.com/projects/4049 : https://github.com/YannGuidon/TinyScanChainCMOS5L:
https://app.tinytapeout.com/projects/4130 : https://github.com/YannGuidon/ttihp-HDSISO8_5L
https://app.tinytapeout.com/projects/4131 : https://github.com/YannGuidon/ttihp-HDSISO8RS_5L
https://app.tinytapeout.com/projects/4132 : https://github.com/ygdes/TinyScanChain5L
https://app.tinytapeout.com/projects/4137 : https://github.com/ygdes/miniMAC_5LThere are shift registers and experiments with the storage density, with an eye on reviving #DTAP - Debug and Test Access Port
And there are attempts to implement #miniMAC - Not an Ethernet Transceiver but they did not succeed. At least the Hammer18 circuit is working well but the gPEAC18 couldn't be ported.
But I'm indescribably thrilled and I can't thank the Tiny Tapeout team enough.
And Jeremy for sponsoring my first 2 tiles :-D
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"Modified DTL" by TI
02/07/2026 at 00:59 • 3 commentsTTL is just a modification of DTL, itself derived from RTL...
In 1967 you could purchase this chip for about 11USD. Barely enough to build a dumb flip-flop.
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Note that ECL would also use transistors as input buffers / impedance adapters but the amplification chain is different and DTL/mDTL/TTL saturate and have a much higher signal swing, much better noise immunity and ... longer cycle times.
The other difference with ECL is the use of complementary transistors, which make it harder to build with old transistors since they are mostly one polarity only. But it's a nice little circuit to analyse :-)
SRC: https://www.facebook.com/photo/?fbid=1419577419961171 (thanks to the author of the macro pictures)
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Vintage bipolar analog switch
01/20/2026 at 00:52 • 1 commentIt's not exactly related to Ted Yapo's blog https://hackaday.io/project/162998-the-rise-and-fall-of-pulses/log/158851-a-toy-diode-sampler but it's close...
Inspired by Curious Marc's recent video:
I had to try a sim with Circuitjs and it works like a charm !
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Why does it matter to me ?
Because I have struggled a LOT to make a DFF gate with bipolar transistors... I had found a version that looked promising for a latch but it became unstable when connected to other devices.
The insights of this pass gate could probably help solve this enigma at last.
Oh and I should get the polarities right....
And then, there is this gem : https://w140.com/tekwiki/images/9/97/Frye_s4_gate.pdf where the value is sampled at the falling edge, almost working as a DFF but with diodes.
Yann Guidon / YGDES
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Bonsoir....je viens de créer une page pour mon projet: https://hackaday.io/project/205190-open-source-plfm-radar-up-to-20km-range .... Je cherche activement des collaborateurs