LR645ND中文資料SUTEX數(shù)據(jù)手冊PDF規(guī)格書

General Description

The Supertex LR645 is a high input voltage, low output current linear regulator. It has a 3-terminal fi xed output voltage version available in TO-92, TO-220 and SOT-89 packages, as well as an adjustable voltage version available in an 8- lead SOIC package. The 3-terminal version functions like any other low voltage 3-terminal regulator except it allows the use of much higher input voltages. When used in a SMPS startup circuit, it eliminates the need for large power resistors. In this application, current is drawn from the high voltage line only during start-up. Only leakage current fl ows after start-up, thereby reducing the continuous power dissipation to a few milliwatts.

Features

? Accepts inputs from 15V to 450V

? Output currents up to 3.0mA continuous, 30mA peak

? Supply current typically 50μA

? Line regulation typically 0.1mV/V

? Output can be trimmed from 8.0V to 12V

? Output current can be increased to 150mA with external FET

Applications

? Off-line SMPS startup circuits (pulse loads)

? Low power off-line regulators

? Regulators for noisy inputs