LM385D-2-5

The LM385D-2-5 is a part of National Semiconductor\'s Voltage Reference family that provides a two-terminal output that is nominally 5 volts. It has excellent temperature stability, low noise, low quiescent current, and low cost. The device has two inputs - one of which is the voltage to be referenced, while the other is a reference terminal which can be tied to the device than referenced to a stable external voltage reference. The LM385D can be used in any application requiring a stable and accurate voltage reference.

Application Field

The LM385D-2-5 is suitable for precision voltage references for a wide range of applications. It is also optimal for use in operational amplifiers, power supplies, linear regulators, battery chargers, motor control applications, and general power conditioning. It can be used in battery-powered and thermally sensitive circuits, where it provides excellent temperature stability, and thus precise voltage control. The LM385D also offers excellent accuracy and low output noise.

Working Principle

The LM385D-2-5 operates on the principle of voltage regulation which is the process of maintaining a constant output voltage despite varying input voltages and load conditions. To do this the device has a zener diode connected across the reference and test terminal. The zener diode creates a voltage drop between these terminals, and this voltage drop sets the output voltage to 5 volts regardless of the input voltage and load condition. When the input voltage is higher than the preset reference voltage, the series transistor turns on and sinks additional current from the output, thus regulating the output voltage.

The LM385D features an impressive temperature stability of .1% typical over a temperature range of +125°C to – 40°C. This stability is achieved by balancing the dynamic and static gains which are both temperature sensitive. The static gain is achieved by utilizing the temperature compensation of the resistor network, while the dynamic gain is achieved by differentiating the gain into separate average, peak and low temperature gain. This allows the device to maintain stable output voltages over a wide range of temperature changes.

The LM385D-2-5s low noise and low quiescent current make it ideal for use in precision voltage reference applications. Its low-noise performance also helps to reduce overall system noise, ensuring a reliable and precise output voltage.

The LM385D-2-5 is an ideal solution for those applications requiring accurate voltage references over a wide temperature range. Its low noise, low quiescent current and excellent accuracy over temperature makes it a great choice for many different applications.