LT1120ACN8#PBF

Linear Voltage Regulators

Linear voltage regulators are primitive yet popular components that are used to regulate the output voltage from a power source. They are usually in a three-terminal integrated circuit (IC) package and consist of a simple linear amplifier that passes a reference voltage to the output, but permits any excess voltage to pass through a bypass diode. This allows the device to pump any extra voltage to ground instead of allowing it to pass through the load.

LT1120ACN8#PBF

The LT1120ACN8#PBF is a three-terminal voltage regulator designed primarily for use in applications where a low dropout voltage is required. It is a variant of the LT1120 family of voltage regulators, which features on-chip current sensing and short-circuit protection. The LT1120ACN8#PBF operates from a wide input voltage range of 2.5V to 36V and is available with output voltages from 1.1V to 15V. It offers very low dropout voltage, fast transient response and good thermal stability.

Applications

The LT1120ACN8#PBF is suitable for a wide range of applications, including portable and desktop PC power supplies, automotive, laptop and telecom power systems, dc-to-dc converters, battery chargers, mobile communication systems and any other systems requiring a low-dropout voltage regulator.

Working Principle

The working principle behind the LT1120ACN8#PBF is fairly simple. The device takes in a positive input voltage from the power source, typically from a battery or a power adapter, and reduces it to a lower voltage which is sent to the output terminals. The on-chip circuit regulates the output voltage to maintain constant output voltage, regardless of input supply voltage or load conditions.

The LT1120ACN8#PBF has an internal reference voltage that is compared to the output voltage. If the output is lower than the reference voltage, then the pass transistor will be turned on and current will flow through the load. Conversely, if the voltage at the output goes beyond the reference voltage, then the pass transistor will be turned off and a bypass diode will conduct and the excess current will be conducted away from the output terminals.

Conclusion

The LT1120ACN8#PBF is a highly-reliable, three-terminal voltage regulator with low dropout voltage, good thermal stability and fast transient response. It is ideal for use in applications requiring low voltage regulation, such as portable and desktop PC power supplies, automotive, laptop and telecom power systems, dc-to-dc converters, battery chargers, mobile communication systems and any other systems requiring a low-dropout voltage regulator.