DQ8051 is a ultra high performance, speed optimized soft core of a single-chip 8-bit embedded controller dedicated for operation with fast (typically on-chip) and slow (off-chip) memories. The core has been designed with a special concern about performance to power consumption ratio. This ratio is extended by an advanced power management unit PMU. DQ8051 soft core is 100% binary-compatible with the industry standard 8051 8-bit microcontroller. DQ8051 has build-in configurable DoCD-JTAG on chip debugger supporting Keil µVision development platform and standalone DoCD debug software. Dhrystone 2.1 benchmark program runs from 19.69 to 26.62 times faster than the original 80C51 at the same frequency. This performance can also be exploited to great advantage in low power applications where the core can be clocked over ten times more slowly than the original implementation for no performance penalty. DQ8051 is fully customizable, which means it is delivered in the exact configuration to meet users’ requirements. There is no need to pay extra for not used features and wasted silicon. It includes fully automated testbench with complete set of tests allowing easy package validation at each stage of SoC design flow.