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LR645

High Input Voltage SMPS, Start-Up/Linear Regulator

Status: In Production

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
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Overview
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Development Environment
Similar Devices
RoHS Information
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Device Overview

Summary

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.

Additional 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

     

Parametrics
Name
Value
+Vin min (V)
15
+Vin max (V)
450
Vout min (V)
8.0
Vout max (V)
12
Output Current (mA)
3
Dimming
N/A
Parallelable
N/A
Package
SOT-89, TO-92, TO-220, 8-Ld SOIC
Features
Trimmable Output, Higher Peak Current Capability,

Documents

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RoHS Information

Part Number
Device Weight (g)
Shipping Weight (Kg)
Lead Count
Package Type
Package Width
Solder Composition
JEDEC Indicator
RoHS
China EFUP
LR645LG-G
0.078000
0.230303
8
SOIC
.150In(3.90mm)
Matte Tin
e3
LR645N3-G
0.203400
0.219000
3
TO-92
-
Matte Tin
e3
LR645N3-G-P003
0.203400
0.515000
3
TO-92
-
Matte Tin
e3
LR645N5-G
1.890200
2.800000
3
TO-220
-
Matte Tin
e3
LR645N8-G
0.051800
0.132000
3
SOT-89
-
Matte Tin
e3
LR645N3-G-P013
0.203400
0.350000
3
TO-92
-
Matte Tin
e3
To see a complete listing of RoHS data for this device, please Click here
Shipping Weight = Device Weight + Packing Material weight. Please contact sales office if device weight is not available.

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