Z5xx is the Central Processing Unit (CPU) used for Toradex Robin and Woodpecker x86 modules.
There are two packages available from the Z530. Both, Robin and Woodpecker, are using the Z530 or Z510, not the Z530P or Z510P due to its smaller form factor and lower power consumption.
Documentation available under: http://www.intel.com/design/intarch/atom/techdocs.htm