Classification of DC/AC converters:
DC/AC converters (hereinafter referred to as inverters) can be basically divided into two categories: single-phase and three-phase. Single-phase inverters are suitable for medium and low power applications, while three-phase inverters are suitable for medium and high power applications. These two categories can be further classified according to the following characteristics:
(1) According to the nature of the input DC power supply: voltage-type inverter circuit (the input power supply is a constant voltage source); current-type inverter circuit (the input power supply is a constant current source).
(2) According to the characteristics of circuit structure: half-bridge circuit; full-bridge circuit; push-pull circuit; other forms.
(3) According to the components of the circuit: ordinary thyristor inverter circuit; high power transistor (GTR) inverter circuit; gate turn-off (GTO) thyristor inverter circuit; MOSFET (MOS field effect transistor) inverter circuit; IGBT inverter circuit, etc.
(4) According to the output waveform: sine wave inverter circuit; non-sine wave inverter circuit.
(III) Integrated voltage regulator
Integrated voltage regulators are solid-state circuits that integrate diodes, transistors, resistors, capacitors, and other components into a single semiconductor or insulating substrate using semiconductor and thin-film processes. The integrated voltage regulator industry has developed rapidly over the past decade, with hundreds of varieties now available both domestically and internationally. Based on circuit operation, integrated voltage regulators can be categorized into linear and switching types. Based on circuit structure, they can be classified as monolithic and combined types. Based on pin connection, they can be categorized as three-terminal and multi-terminal types. Based on manufacturing process, they can be categorized into semiconductor integrated voltage regulators, thin-film hybrid integrated voltage regulators, and thick-film hybrid integrated voltage regulators.
Integrated voltage regulators are voltage-regulating circuits fabricated on semiconductor silicon wafers using processes such as epitaxy, oxidation, photolithography, diffusion, and metal evaporation. The various components of such integrated voltage regulators are manufactured in the same process, resulting in high reliability and improved voltage regulation accuracy, while also reducing size and weight.
Common integrated voltage regulators include the following types:
(1) Multi-terminal adjustable integrated voltage regulator. This type of voltage regulator requires external connection for the sampling resistor and protection circuit components. It has multiple external terminals to facilitate adaptation to different applications. Its output voltage is adjustable to meet different output voltage requirements.
(2) Three-terminal fixed integrated voltage regulator. This type of voltage regulator has three terminals: input, output, and common terminal. The output voltage is fixed (generally divided into several levels). This type of product has the advantages of being easy to use, having stable performance, and being inexpensive. It has been widely used and has basically replaced voltage regulator circuits composed of discrete components.
(3) Three-terminal adjustable integrated voltage regulator. It has three terminals: input, output, and adjustment. Connecting two external resistors to the adjustment terminal allows for continuous adjustment of the output voltage. This type of integrated voltage regulator is suitable for applications requiring high voltage regulation accuracy and where the output voltage needs to be arbitrarily adjusted within a certain range. It also comes in positive and negative output voltage and output current versions; careful attention should be paid to the electrical parameter characteristics of each series of integrated voltage regulators when selecting one.