DER-049: -12V @ 250mA, 106 ~ 265VAC in

Summary

This document is an engineering prototype report describing a non-isolated -12 V, 250mA power supply utilizing a LNK305P.

The document contains the power supply specification, schematic, bill-of-materials, printed circuit layout, and performance data.

The circuit shown in Figure 2 is a non-isolated buck-boost (inverting) topology. The input voltage range is 108 to 265VAC 50/60Hz and provides a regulated –12V at 250mA. The buck-boost topology is essentially the non-isolated version of the Flyback Converter, in that the transformer is replaced with a single low cost inductor (L2).

Specifications

Manufacturer Power Integrations
Category AC/DC and DC/DC Conversion
Sub-Category AC/DC SMPS - Single Output
Eval Board Board not Stocked
AC Voltage 115 V
230 V
Universal (115 / 230V)
190 V
208 V
Outputs and Type 1 Non-Isolated
Voltage Out -12 V
Current Out 250 mA
Output Power 3 W
Features Current Limit (Adj. or Fixed)
Frequency Jitter for EMI
Open Circuit Protection
Short Circuit Protection
Thermal Protection
Efficiency @ Conditions >62%, 265 VAC, 12V @ 100 ~250 mA
>62%, 240 VAC, 12V @ 85 ~ 250 mA
>62%, 120 VAC, 12V @ 50 ~ 250 mA
>62%, 108 VAC, 12V @ 50 ~ 250 mA
No-load Input Power @ Voltage 200 mW @ 240 V
Switching Frequency 66 kHz
Internal Switch Yes
Component Count + Extras 15 + 0
Voltage In 108 ~ 265 VAC
Design Author Power Integrations
Application / Target Market White Goods
Main I.C. Base Part LNK305
Date Created By Author 2005-04
Date Added To Library 2014-07