LT1009IDR

The LT1009IDR is a low-power, precision, three-terminal adjustable shunt regulator from Linear Technology. This monolithic device is designed for applications requiring a wide input-voltage range, low quiescent current, and fast transient-response characteristics. The LT1009IDR’s excellent line and load regulation and low-temperature drift make it ideal for use in many systems where precise control of the output voltage is required. Additionally, the LT1009IDR is well suited for use in applications where a regulated voltage reference is needed.

The LT1009IDR is specifically designed to perform in applications where the adjustable reference must be stable under dynamic load conditions. Its adjustable output voltage can be readily set to any value, between one and nine volts, by means of an external resistor divider. An internal emitter follower provides a low output impedance, which makes the LT1009IDR ideal for applications requiring fast line and load transient responses.

The LT1009IDR’s wide input-voltage range, low quiescent current, and fast transient response make it an ideal voltage reference for precision analog/digital conversion circuits, potentiometer references, and high-performance power supplies. In addition, its low output impedance and fast settling time make it an ideal reference for fast A/D and D/A converters. The LT1009IDR is also well-suited for use in high-precision analog and digital current-sensing circuits, transimpedance amplifiers, and low-noise amplifiers.

The LT1009IDR operates as an adjustable voltage regulator with an external voltage reference as the feedback. Its internal parts include an NPN bipolar transistor, an adjustable current source, a temperature-compensated reference, and an external voltage reference. The current source, which is driven by the output voltage, is adjusted to match the reference voltage. The output voltage is then regulated to match the reference. In this way, the output voltage of the LT1009IDR is accurately maintained, even under changing line, load, and temperature conditions. The LT1009IDR is available in eight-pin SOT-23 and TO-92 packages, as well as a two-pin TO-18 hermetically sealed package.