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  • OPA955

    From john larkin@3:633/10 to All on Monday, July 27, 2026 14:16:21

    https://www.ti.com/product/OPA955

    They call this a TIA but it's really an opamp. Fast, low noise, at
    least above 10KHz.


    --- PyGate Linux v1.5.19
    * Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)
  • From Phil Hobbs@3:633/10 to All on Monday, July 27, 2026 21:56:25
    john larkin <jl@htigct.com> wrote:

    https://www.ti.com/product/OPA955

    They call this a TIA but it's really an opamp. Fast, low noise, at
    least above 10KHz.



    Probably best for capacitive sources like photodiodes?GBW of 11 GHz and
    2750 V/us is pretty lopsided!

    Cheers

    Phil Hobbs

    --
    Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics

    --- PyGate Linux v1.5.19
    * Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)
  • From john larkin@3:633/10 to All on Monday, July 27, 2026 15:39:39
    On Mon, 27 Jul 2026 21:56:25 -0000 (UTC), Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:

    john larkin <jl@htigct.com> wrote:

    https://www.ti.com/product/OPA955

    They call this a TIA but it's really an opamp. Fast, low noise, at
    least above 10KHz.



    Probably best for capacitive sources like photodiodes?GBW of 11 GHz and
    2750 V/us is pretty lopsided!

    Cheers

    Phil Hobbs

    They suggest using it with APDs.

    But it may be vaporware. TI has been doing that lately, announcing
    parts you can't get with a disclaimer that maybe you never will.

    I was going to use a cool IC dc/dc converter, UCC33421, but it was
    mostly bait-and-switch.

    We finally got a few samples, but delivery is November, maybe.

    The other thing TI is doing is 2-page "data sheets" with almost no
    content. I hope the bean counters haven't taken over.


    --- PyGate Linux v1.5.19
    * Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)
  • From john larkin@3:633/10 to All on Tuesday, July 28, 2026 12:19:16
    On Mon, 27 Jul 2026 15:39:39 -0700, john larkin <jl@htigct.com> wrote:

    On Mon, 27 Jul 2026 21:56:25 -0000 (UTC), Phil Hobbs ><pcdhSpamMeSenseless@electrooptical.net> wrote:

    john larkin <jl@htigct.com> wrote:

    https://www.ti.com/product/OPA955

    They call this a TIA but it's really an opamp. Fast, low noise, at
    least above 10KHz.



    Probably best for capacitive sources like photodiodes?GBW of 11 GHz and >>2750 V/us is pretty lopsided!

    Cheers

    Phil Hobbs

    They suggest using it with APDs.

    But it may be vaporware. TI has been doing that lately, announcing
    parts you can't get with a disclaimer that maybe you never will.

    I was going to use a cool IC dc/dc converter, UCC33421, but it was
    mostly bait-and-switch.

    We finally got a few samples, but delivery is November, maybe.


    Got some!

    https://www.dropbox.com/scl/fi/ctghu8a23t7yr9rgxiy9u/UCC33421.jpg?rlkey=q8adhuy3tnwu8ajqaptv1xdic&raw=1

    Got to admit it's slick, a fraction of the size of a potted dc/dc
    converter. And the 5v output is regulated.

    I'll test it for noise and such, and have it x-rayed.


    --- PyGate Linux v1.5.19
    * Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)