REF194ESZ

A voltage reference is an electronic device used to maintain a fixed reference voltage over changes in environmental conditions, temperature and power supply voltage variation. It is also known as a voltage regulator or a voltage stabilizer. Voltage references are used in many applications ranging from personal computers, appliances and industrial equipment, to gas pumps and instrumentation. While many voltage references are available in ICs, a transistor based voltage reference, such as the REF194ESZ, provides a relatively inexpensive and flexible solution.

Applications of REF194ESZ

The REF194ESZ is a low-noise, low-dropout, three-terminal adjustable linear voltage reference. It is designed to operate with a single supply or dual power supplies of an arbitrary voltage up to 36V. Due to its low voltage dropout and low noise characteristics, the REF194ESZ is a popular choice for many applications, especially those requiring a well-regulated supply voltage. This includes a wide range of industrial and automotive applications, including oil/gas pumps, motor control, LED control, power supply and digital devices, and optical amplitude modulation.

The REF194ESZ can also be used for relative signal measurements, such as sensing the output voltage of a motor drive, etc. The device can be used to generate the reference voltage to a power amplifier circuit or a digital signal processing circuit to maintain accuracy. It can also be used to detect the output signal from a signal processing circuit. Additionally, the device can be used as a comparator in a comparator circuit to compare input signals with its reference voltage.

Working Principle

The REF194ESZ voltage reference has an operating principle based on a transistor based monolithic resistor array. The monolithic resistor array consists of four resistors which are connected in series. Each of these resistors have a specific resistance, with the second resistor in the array having the highest value of resistance. By connecting the four resistors in series, the total output resistance of the reference diminishes, giving an output voltage of around 1.2V. The output voltage is also temperature compensated, as the thermistors change their values as the temperature of the external environment changes.

The REF194ESZ also has two transistors connected in series between the third and fourth resistors. When voltage is applied to the transistors, a variable divide ratio is created. This allows the device to maintain the output voltage and regulating circuit without any additional components, giving it its low-cost, low-noise and low-voltage dropout characteristics.

In conclusion, the REF194ESZ is an excellent choice for a wide range of applications due to its low voltage dropout, low noise, and adjustable output voltage characteristics. It is ideal for industrial, automotive and instrumentation applications, as well as LED control, wireless communication and relative signal measurement applications. Its adjustable output voltage allows it to be used as a reference voltage in comparator circuits and signal processing stages.