BD9528AMUV Datasheet, PDF (17/30 Pages) Rohm – High Performance Regulators for PCs Main Power Supply for Notebook PCs(With Built-in Linear Regulator)

BD9528AMUV
・Timer Latch Type Short Circuit Protection
FB
REF×0.7
SCP ^0.75ms(typ)
EN / UVLO
Technical Note
Short protection kicks in when output falls to or below
REF X 0.7.
When the programmed time period elapses, output is
latched OFF to prevent destruction of the IC. (HG=Low,
LG=Low) Output voltage can be restored either by
reconnecting the EN pin or disabling UVLO.
・Over Voltage Protection
REF×1.2
FB
HG
LG
Switching
・Over current protection circuit
tON
tON
tON
HG
LG
IL
When output rise to or above REF×1.2 (typ), output
over voltage protection is exercised, and low side FET
goes up maximum for reducing output.(LG=High,
HG=Low).When output falls, output voltage can be
restored., and go back to the normal operation.
tON
During the normal operation, when FB becomes less
than REF, HG becomes High during the time tON, and
after HG becomes OFF, it output LG.
However, when inductor current exceeds I_LIMIT
threshold, next HG pulse doesn’t pulsate until it is lower
than ILIMIT level.
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2011.11 - Rev.A