AN2937 Datasheet, PDF (1/41 Pages) STMicroelectronics – Power system demonstration kit based on the PM6686 dual

AN2937
Application note
Power system demonstration kit based on the PM6686 dual
step-down controller with adjustable voltages and adjustable LDO
Introduction
The PM6686 is a dual step-down controller with adjustable output voltages, adjustable LDO
and charge pump circuit for notebook power systems. The PM6686 demonstration kit for
system supply represents a typical application circuit, and allows testing of all the functions
of the PM6686 device. It provides two switching sections with 5 V (OUT1) and 3.3 V (OUT2)
outputs from 8 V to 28 V input battery voltage. The operating switching frequency of the two
sections is 400 kHz and 300 kHz, respectively. Each switching section delivers more than 5
A of output current. An internal linear regulator can provide 5 V at 100 mA peak current. The
charge pump circuit provides an auxiliary 12 V output voltage.
Figure 1. PM6686 demonstration kit for system supply
August 2009
Doc ID 15418 Rev 1
1/41
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