SI9183DT-AD-T1-E3

SI9183DT-AD-T1-E3: Application Field and Working Principle

The SI9183DT-AD-T1-E3 device is a linear voltage regulator belonging to the power management integrated circuit (PMIC) family. It typically is used for supplying VBAT rails that require a low noise, high-efficiency low dropout linear regulator. The device is well equipped with the functionality necessary to easily apply it in a wide range of power-supply applications. This article will provide details on its application field and working principle.

Application Field

The SI9183DT-AD-T1-E3 has multiple features that make it suitable for a wide range of applications. It has a wide input voltage range of 5V to 18V, and its output voltage is adjustable from 0.8V to 3.6V. In addition, its output current capability is up to 3A and its dropout voltage is only 0.7V at the full load of 3A. This makes the device suitable for many applications, including overclocking communication systems, ultra-low-power HDDs, backup battery packs, automotive, industrial, and consumer applications.

The device also includes several added functionalities that make it suitable for several advanced power applications. It includes a programmable turn-off point for a varying UVLO (under-voltage lockout) as well as an adjustable soft-start. These features are especially useful in automotive, industrial and consumer applications where high-efficiency and low input/output ripple are required.

Working Principle

The SI9183DT-AD-T1-E3 works by converting the input voltage to its regulated output voltage, plus some internal losses. The regulator does this using a control loop created with a power transistor, a voltage reference, and an error amplifier. The power transistor is the main component of the linear regulator. It controls the voltage by diverting the energy from the regulator\'s input to ground.

The regulator starts by sensing the input voltage, VIN. The reference voltage then compares the input to a set level, and the error amplifier amplifies this difference. The error amplifier is connected to and will drive the power transistor to maintain the output voltage to a certain level. This is done by diverting the desired amount of energy to the load and any excess to ground.

The gain of the amplifier is chosen to range from small values to large values, depending on the application. This large range of amplification introduces the feature of adjustable line regulation and the current mode of operation is chosen depending on the amount of load current being drawn. This combination of the power transistor, voltage developer, and error amplifier creates a complete control loop providing the desired level of efficiency and voltage regulation.