MP2618 MPS, MP2618 Datasheet - Page 6

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

PIN FUNCTIONS
MP2618 Rev. 0.92
7/14/2010
1,10,12,22
11, 21
25, 26
Pin #
13
14
15
16
17
18
19
20
23
24
27
28
2
3
4
5
6
7
8
9
Exposed
CHGOK
VREF33
VREF25 Internal linear regulator 2.5V reference output.
COMPV VLOOP Compensation. Decouple this pin with a capacitor and a resistor.
COMPI ILOOP Compensation. Decouple this pin with a capacitor and a resistor.
CELLS
ACOK
SHDN
Name
OUT1
GND,
BATT
TMR
NTC
RG1
RG2
VCC
CSP
MP2618 – 2A, 24V INPUT, 600kHz 2-3CELL SWITCHING LI-ION BATTERY CHARGER
BST
Pad
PIN
AIN
EN
SW
NC
Switch Output.
Description
No Connection
Thermistor Input. Connect a resistor from this pin to the pin VREF33 and the Thermistor
from this pin to ground.
Valid Input Supply Indicator. A logic LOW on this pin indicates the presence of a valid
input supply.
Charging status Indicator. A logic LOW indicates charging operation. The pin will become
an open drain once the charging is stopped.
Internal linear regulator 3.3V reference output. Bypass to GND with a 1µF ceramic
capacitor.
On/Off Control Input.
Shutdown control of current sense amplifier. Connect this pin to
Gain Resistor of current sense amplifier.
Ground. This pin is the voltage reference for the regulated output voltage. For this reason
care must be taken in its layout. This node should be placed outside of the D1 to C1
ground path to prevent switching current spikes from inducing voltage noise into the part.
Connect exposed pad to ground plane for optional thermal performance.
Output for Driving Resistor Load.
Gain Resistor of current sense amplifier.
Power Input of current sense amplifier.
Command Input for the Number of Li-Ion Cells. Make this pin float for 3-cell operation or
connect this pin to ground for 2-cell operation.
Positive Battery Terminal.
Battery Current Sense Positive Input. Connect a resistor RS1 between CSP and BATT.
Set time constant. 0.1uA charge and discharge the external cap. Connect TMR pin to
GND to disable the internal timer.
Bootstrap. This capacitor is needed to drive the power switch’s gate above the supply
voltage. It is connected between SW and BST pins to form a floating supply across the
power switch driver.
Power Supply Voltage. The MP2618 operates from a +5.5V to +24V unregulated input.
C1 is needed to prevent large voltage spikes from appearing at the input.
Controller Supply Voltage.
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2010 MPS. All Rights Reserved.
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EN
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