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, Panasonic LX100 has a 13.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor and features Venus Engine processor.
Below you can see the LX7 and LX100 sensor size comparison.
As seen above, Panasonic LX100 has a 5.4x Larger sensor area than Panasonic LX7. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.