MP2618 MPS, MP2618 Datasheet - Page 12

• Manufacturer Part Number: MP2618
• Description: 2a, 24v Input, 600khz 2-3 Cell Switching Li-ion Battery Charger With System Power Path Management
• Manufacturer: MPS

Negative
Thermistor
The MP2618 has a built-in NTC resistance
window comparator, which allows MP2618 to
sense the battery temperature via the thermistor
packed internally in the battery pack to ensure a
safe operating environment of the battery. A
resistor
connected from VREF33 to NTC pin and the
thermistor is connected from NTC pin to GND.
The voltage on NTC pin is determined by the
resistor divider whose divide ratio depends on
the battery temperature. When the voltage of pin
NTC falls out of NTC window range, MP2618 will
stop the charging. The charger will restart if the
temperature goes back into NTC window range.
MP2618 Rev. 0.92
7/14/2010
with
MP2618 – 2A, 24V INPUT, 600kHz 2-3CELL SWITCHING LI-ION BATTERY CHARGER
Thermal
appropriate
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Coefficient
value
should
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www.MonolithicPower.com
(NTC)
be
Power Path Management
MP2618 can implement a switching charger
circuit with power path management function,
which realizes the current sharing of the charger
and system load. In other words, MP2618 senses
the system current and feeds it back, then
reduces charge current according to the increase
of the system current.
However, after the charge current decrease to 0,
the system current can only be limited by the
adapter.
The system current is satisfied first and always. It
chooses the adapter as its power source when
the adapter plugs in, and the battery is the
backup power source when the adapter is
removed.
Figure 3 to Figure 6 shows the charge profile,
operation waveform and flow chart, respectively.
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