Sony TX20 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features BIONZ processor. On the other hand, Nikon S3500 has a
20.0MP 1/2.3-inch (6.16 x 4.62 mm ) sized CCD sensor .
Below you can see the TX20 and S3500 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony TX20 and Nikon S3500 Cameras
Sony TX20 and Nikon S3500 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Sony TX20
or the
Nikon S3500 ,
including hyperfocal distance.