MP6231/MP6232 –CURRENT-LIMITED POWER DISTRIBUTION SWITCHES
FUNCTION BLOCK DIAGRAM
Figure 2—Functional Block Diagram
DETAILED DESCRIPTION
Over Current
When the load exceeds trip current (minimum
threshold current triggering constant-current
mode) or a short is present, MP6231/MP6232
switches into to a constant-current mode (current
limit value). MP6231/MP6232 will be shutdown
only if the overcurrent condition stays long
enough to trigger thermal protection.
Trigger overcurrent protection for different
overload conditions occurring in applications:
1) The output has been shorted or overloaded
before the device is enabled or input applied.
MP6231/MP6232 detects the short or
overload and immediately switches into a
constant-current mode.
2) A short or an overload occurs after the device
is enabled. After the current-limit circuit has
been tripped (reached the trip current
threshold), the device switches into constant-
current mode. However, high current may
flow for a short period of time before the
current-limit circuit can react.
3）Output current has been gradually increased
beyond the recommended operating current.
The load current rises until the trip current
threshold is reached or until the thermal limit
of
the
device
is
exceeded.
The
MP6231/MP6232 is capable of delivering
current up to the trip current threshold without
damaging the device. Once the trip threshold
has been reached, the device switches into its
constant-current mode.
Flag Response
The FLAG pin is an open drain configuration.
This FAULT will report a fail mode after an 8ms
deglitch timeout. This is used to ensure that no
false fault signals are reported. This internal
deglitch circuit eliminates the need for extend
components. The FLAG pin is not deglitched
during an over temp. or a voltage lockout.
MP6231/MP6232 Rev. 1.2
3/31/2010
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