LR645数据手册集成电路（IC）的线性+开关稳压器规格书PDF

描述 Description

LR645 is a high input voltage, low output current linear regulator. It has a 3-terminal fixed 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 start-up 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 flows after start-up, thereby reducing the continuous power dissipation to a few milliwatts.The adjustable voltage version allows trimming of the output voltage from 8.0 to 12V. This version can also be connected to an external depletion mode MOSFET for increased output current. When used in conjunction with depletion mode MOSFET DN2540N5, an output current of up to 150mA is achieved.

特性 Features

Accepts inputs from 15 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 8.0 to 12V
Output current can be increased to 150mA with external FET

简介

LR645属于集成电路（IC）的线性+开关稳压器。由制造生产的LR645稳压器 - 线性线性稳压器用于提供稳定的输出电压，无论负载电流、输入电压或环境因素如何变化，这些输出电压通常都要保持不变。它们的工作原理要求输入电压维持在高于所需的输出电压，而且要超出某个最小量，并且在工作时会将输入端的任何多余电压转换为热量。对于大多数应用而言，虽然这种稳压器的效率低于开关模式的稳压器，但它们通常更适合对噪声高度敏感的应用。