Replace TSOP-28 package with soic-8

[jimmykk]

Hi
I want to replace obsolete component in TSOP-28 (0.55mm pitch, 13.4 x 8mm package) with SOIC-8 (1.27mm pitch, 5x6mm size) on my PCB. The TSOP package has all the 8 pins which I need on the left side of package. The way I see to replace this package is to make a very small rigid flex PCB with only the new SOIC8 package soldered on rigid PCB and the flex part having plated vias(in a row) connecting to the pads of TSOP. Is this practically possible or pitch of TSOP too small for the via soldering.
any other ideas?

 

[FvM]

Why rigid flex? You can reflow solder a rigid adapter board to the TSOP footprint.

 

[jimmykk]

ok..but does it come in SOIC-8(8Pin) to TSOP-28(28 Pin) adapter? Also, We do not have holes on my PCB to mount this adapter board.

 

[ZASto]

Any photo of existing board and datasheets of the IC's (old and new)?

 

[FvM]

ok..but does it come in SOIC-8(8Pin) to TSOP-28(28 Pin) adapter? Also, We do not have holes on my PCB to mount this adapter board.

You'll design your own adapter with pads on the bottom side, SMD reflow mount similar to chip scale package ICs

 

[jimmykk]

**broken link removed** TSOP-28 which is obsolete and AT45DB081E-SSHN-B SOIC8(8S1) is the one i want to replace it with.

--- Updated Apr 19, 2021 ---

You'll design your own adapter with pads on the bottom side, SMD reflow mount similar to chip scale package ICs

OK. I was thinking it the easy way if there is any adapter board that is readily available from market.
But even if i design my own adapter board with pads on Bottom side, how can i solder it on the respective pads of TSOP, unless i have a via in pad kind of solution that goes from Top to Bottom side.

 

[FvM]

The suggestion was reflow solder, preferably with hot air. The adpater board will surely have vias, but probably not in the pad area.

 

[jimmykk]

THanks.. i found a more reasonable approach that would fit in my case is using castellated holes on PCB edges. Just need to check with manufacturer that they can produce such holes with 0.55mm pitch and diameter of 0.25/0.3mm