Mixed signal devices are available as standard parts, but custom designed application-specific integrated circuits (ASICs) are designed for new applications or if new standards are emerging or new energy source(s) are implemented in the system and the production volumes are estimated to be high. Availability of ready and tested analog and mixed signal IP blocks from foundries or dedicated design houses have lowered the gap to realize mixed signal ASICs. There also exists few mixed signal FPGAs and microcontrollers, which typically may include analog-to-digital and digital-to-analog converter(s), operational amplifiers, even wireless connectivity blocks etc. on the same chip with digital logic. Mixed signal FPGAs are an extension of field-programmable analog arrays. These mixed signal FPGAs and microcontrollers are bridging the gap between standard mixed signal devices, full custom ASICs and possibly embedded software world, when products are under development or the volumes are too low for an effective full custom ASIC realization. However there can be few performance limitations typically with these type of FPGAs and microcontrollers like resolution of ADCs, speed of digital to analog conversion (DAC) and limited number of inputs and outputs etc. Despite of these possible limitations mixed signal FPGAs and microcontrollers can speed up the system architecture design, prototyping and even small and medium scale production. They also can be backed-up with development boards, development community and possibly also software support.