DQ80251 is a revolutionary Quad-Pipelined ultra high performance, speed optimized soft core of a 16-bit/32-bit embedded microcontroller. The core has been designed with a special concern for performance to power consumption ratio. This ratio is extended by an advanced power management unit PMU. This product is build based on 13 years of DCD’s know-how with triumphant 8051 architectures. DQ80251 soft core is 100% binary-compatible with the industry standard 16-bit 80C251 and 8-bit 80C51 microcontrollers. There are two working modes of the DQ80251: BINARY where original 80C51 compiled code is executed, and SOURCE which is native 80C251 mode using all DQ80251 performance. DQ80251 has build-in configurable DoCD-JTAG on chip debugger supporting Keil DK251 and standalone DoCD debug software. Dhrystone 2.1 benchmark program runs 66 times faster than the original 80C51 and more than 5 times faster than the original 80C251 at the same frequency. This performance can be also exploited to great advantage in low power applications where the core can be clocked over fifty times slower than the original implementation for no performance penalty. Additionally compiled code size for SOURCE mode is about 2 times smaller comparing to identical standard 8051 code, since DQ80251 instructions are more effective.