The paper focuses on the design, testing, and construction of three power electronic building blocks. They are a zero crossing detector, a voltage isolation module, and a current isolation module. Each of the modules run on a unipolar supply of 5Vdc and can accept high voltages and currents.
The zero crossing detector can accept a 240Vac at 50Hz mains power supply as its input and output a TTL signal accurate to 15ms.
The voltage isolation module has two switches associated with the circuit. The first switch lets the user choose between a "x 100 probe" or a "x 200 probe" that reduces the input voltage by a factor of 100 or 200. The second switch allows the output voltage to be referenced to either 0V or 2.5Vdc.
The "x 100 probe" is generally used for DC voltage inputs with a reference voltage of 0V. This module proved to be very accurate over a range of 4Vdc to 60Vdc. Although the paper shows that the module is capable of handling voltages exceeding 400Vdc.
The "x 200 probe" is generally used for 240Vac mains power input and is used with a reference voltage of 2.5Vdc to obtain both positive and negative peaks of the input wave. It is very accurate over a voltage range of 12Vac to 240Vac.
The module returns a common-mode rejection ratio of 47dB, a 3-dB point of 600kHz, and a gain-bandwidth product of 1MHz.
The current isolation module can accept AC and DC currents over a range from 0A to 20A.
The module contains a switch that allows the user to switch between three current settings; 5A, 10A, and 20A depending on the magnitude of the input current. This module is accurate over the range of 0A to 2A.