Panasonic LX7 has a 10.0MP 1/1.7 (7.44 x 5.58 mm ) sized CMOS sensor and features Venus Engine processor. On the other hand, Olympus XZ-2 iHS has a 12.0MP 1/1.7" (7.44 x 5.58 mm ) sized CMOS sensor .
Below you can see the LX7 and XZ-2 iHS sensor size comparison.
Panasonic LX7 and Olympus XZ-2 iHS have sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Panasonic LX7 has 18% larger pixel area compared to Olympus XZ-2 iHS, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.