AS1313 datasheet(13/26 Pages) AMSCO

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ams Datasheet

Page 13

[v1-43] 2015-Jul-23

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AS1313 − Detailed Description

If the VOUT falls below the VOUT_nom, SW1 closes and the coil

current increases until the max. coil current of 400mA is

reached. During this time tON, the VOUT increases. With reaching

the 400mA, the switch SW1 opens immediately, the SW2 closes

and the coil current decreases down till it reaches the zero line.

After this, SW2 opens and if the VOUT is then above the

VOUT_nom, no further pulse is needed, both switches remain in

their open position, hence no coil current is flowing. In this

phase the needed output power only comes out of the COUT.

This time is called tWAIT, which takes ~100us. If the VOUT falls

below VOUT_nom within the time tWAIT, the SW1 closes and the

charging cycle starts again.

If the VOUT is still higher than VOUT_nom after tWAIT is elapsed,

then the AS1313 falls into an idle mode, which results in a

reduction of the quiescent current. Once, the AS1313 is in this

idle mode, the idle-comparator is comparing VOUT with VIDLE

(98% of VOUT_nom) and SW1 closes as soon as the VOUT reaches

this threshold.

AS1313 データシート(PDF) 13 Page - ams AG