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LR745

High Input Voltage SMPS, Start-Up

Status: In Production

Features:

  • Accepts inputs from 35 to 450V
  • Output current limiting
  • For PWM ICs with start-up threshold voltage of 13.9 - 18.0V
  • Very low power consumption after start-up
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Overview
Documents
Development Environment
Similar Devices
RoHS Information
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Device Overview

Summary

LR745 is a high input voltage SMPS start-up circuit. The LR745 is ideally suited for use with industry standard low voltage PWM ICs having start thresholds of 13.9 to 18.0V. It allows the PWM ICs to be operated from rectified 120 or 240VAC lines, and eliminates the use of power resistors often used for this purpose. The internal circuitry of the LR745 allows the PWM ICs to operate at a VCC voltage below their start threshold voltage after start-up. The auxiliary voltage can be less than the start threshold voltage, which allows for improved efficiency.Current from the high voltage line is drawn only during the start-up period. After start-up, the internal high voltage line is disconnected from the IC, thereby reducing the continuous power dissipation to a minimum.

Additional Features
  • Accepts inputs from 35 to 450V
  • Output current limiting
  • For PWM ICs with start-up threshold voltage of 13.9 - 18.0V
  • Very low power consumption after start-up
Parametrics
Name
Value
+Vin min (V)
35
+Vin max (V)
450
Vout min (V)
13.9
Vout max (V)
18
Output Current (mA)
3
Dimming
N/A
Parallelable
N/A
Package
SOT-89, TO-92
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
LR745N8-G
0.051800
0.132000
3
SOT-89
-
Matte Tin
e3
LR745N3-G
0.203400
0.219000
3
TO-92
-
Matte Tin
e3
LR745N3-G-P003
0.203400
0.515000
3
TO-92
-
Matte Tin
e3
LR745N3-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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