suggested substitution for SN74CBT3253 TSSOP

[va3rr]

I was playing around with the JLCPBC ordering page and, as forewarned by OM Manuel, the SN74ACT is out-of-stock. No problem, as this SOIC is available elsewhere, and perhaps not too difficult to hand solder.

However, the SN74CBT3253 16 pin TSSOP is also out-of-stock. This is a little more worrisome, as TSSOP may be a little to difficult for many of us senior citizens to hand solder.

There were also some of the 1NF 0805 caps out-of-stock and the 68 pF 0603, but I hope these shortages will be temporary? If not, I guess we can hand solder those as well.

Could someone suggest appropriate substitutions for the SN74CBT3253 TSSOP-16? I must profess ignorance (in the classical sense) in this regard...

merci d'avance.
Russ, va3rr

[DL2MAN]

Hi Russ,

The 74CBT3253 in TSSOP is available here:
https://www.mouser.de/ProductDetail/Tex ... Ct3Q%3D%3D

Larger Packages, like the FST3253 in the package on the original QCX is unfortunately no longer produced...

There´s plenty of other options for 1NF 0805 caps 68 pF 0603.
If it´s on Mainboard, options are endless.
On RF Board there´s also plenty of possible substitutes.
You can use any 0805 or 0603 cap with the right value with C0G or NP0 dielectricum as long as it´s rated for 100V or higher. The (tr)uSDX was designed for high flexibility in that regard.

73 Manuel; DL2MAN

[va3rr]

Thanks Manuel. Having to hand-solder a TSSOP-16 may be a show-stopper for some of my group, so I will have to canvass them before I move forward...

I appreciate your quick response as well as making this project available to us...

vy 73
Russ

[Shirley Dulcey KE1L]

Does this design use the SN74CBT3253 or the SN74CBT3253C? (That second C matters; the two versions of the chip implement the select lines differently, so swapping them requires a minor circuit change.) The FST3253 in TSSOP is a direct replacement for the latter; the second C indicates the version that is Compatible with it.

[Faraaz VK4JJ]

Does this design use the SN74CBT3253 or the SN74CBT3253C? (That second C matters; the two versions of the chip implement the select lines differently, so swapping them requires a minor circuit change.) The FST3253 in TSSOP is a direct replacement for the latter; the second C indicates the version that is Compatible with it.

No difference.

[wa2t]

Does this design use the SN74CBT3253 or the SN74CBT3253C? (That second C matters; the two versions of the chip implement the select lines differently, so swapping them requires a minor circuit change.) The FST3253 in TSSOP is a direct replacement for the latter; the second C indicates the version that is Compatible with it.

No difference.

There is in fact a difference, as Shirley points out. However, the select lines are both tied to ground on the (tr)uSDX design, so I do not think this difference makes a difference.

73,

Robert, WA2T

[wa2t]

There is in fact a difference, as Shirley points out. However, the select lines are both tied to ground on the (tr)uSDX design, so I do not think this difference makes a difference.

73,

Robert, WA2T

The SN74CBT3253 "C" version is a good substitute, this is what I am using on my boards and they work fine.

73,

Robert, WA2T