MCP73827-4.1VUATR Microchip Technology, MCP73827-4.1VUATR Datasheet - Page 13

• Manufacturer Part Number: MCP73827-4.1VUATR
• Description: IC CONTROLLR LI-ION 4.1V 8-MSOP
• Manufacturer: Microchip Technology

Specifications of MCP73827-4.1VUATR

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion)
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -20°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
• Output Voltage: 4.141 V
• Operating Supply Voltage: 4.5 V to 5.5 V
• Supply Current: 560 mA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 20 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MCP738274.1VUATR

Worst case, V
source, 100 mΩ, 1% sense resistor, and a maximum
sink voltage of 1.6V is:
At this worst case V
must be low enough as to not impede the performance
of the charging system. The maximum allowable
R
The Fairchild NDS8434 and International Rectifier
IRF7404 both satisfy these requirements.
6.1.1.3
The MCP73827 is stable with or without a battery load.
In order to maintain good AC stability in the constant
voltage mode, a minimum capacitance of 10 µF is rec-
ommended to bypass the V
itance provides compensation when there is no battery
load. In addition, the battery and interconnections
appear inductive at high frequencies. These elements
are in the control feedback loop during constant voltage
mode. Therefore, the bypass capacitance may be nec-
essary to compensate for the inductive nature of the
battery pack.
Virtually any good quality output filter capacitor can be
used, independent of the capacitor’s minimum ESR
(Effective Series Resistance) value. The actual value of
the capacitor and its associated ESR depends on the
forward trans conductance, g
external pass transistor. A 10 µF tantalum or aluminum
electrolytic capacitor at the output is usually sufficient
to ensure stability for up to a 1 A output current.
6.1.1.4
The optional reverse blocking protection diode
depicted in Figure 6-1 provides protection from a
faulted or shorted input or from a reversed polarity input
source. Without the protection diode, a faulted or
shorted input would discharge the battery pack through
the body diode of the external pass transistor.
© 2007 Microchip Technology Inc.
R
DSON
DSON
V
R
V
I
R
OUT
GS
DSON
INMIN
SENSE
at the worst case V
=
=
is the maximum peak fast charge current
1.6V
EXTERNAL CAPACITORS
REVERSE BLOCKING PROTECTION
4.5V 758mA 99mΩ
--------------------------------------------------------------------------------
is the minimum input voltage source
=
is the sense resistor
V
--------------------------------------------------------------------------------------------- -
GS
INMIN
–
–
(
4.5V 758mA
with a 5V, +/-10% input voltage
GS
–
758mA
–
I
, the R
PEAK
×
GS
BAT
m
×
I
is:
OUT
, and capacitance of the
pin to GND. This capac-
DSON
R
×
SENSE
–
99mΩ
4.242V
of the MOSFET
–
)
V
=
BATMAX
=
–
242mΩ
2.8
V
If a reverse protection diode is incorporated in the
design, it should be chosen to handle the peak fast
charge current continuously at the maximum ambient
temperature. In addition, the reverse leakage current of
the diode should be kept as small as possible.
6.1.1.5
In the stand-alone configuration, the shutdown pin is
generally tied to the input voltage. The MCP73827 will
automatically enter a low power mode when the input
voltage is less than the output voltage reducing the bat-
tery drain current to 8 µA, typically.
By connecting the shutdown pin as depicted in
Figure 6-1, the battery drain current may be further
reduced. In this application, the battery drain current
becomes a function of the reverse leakage current of
the reverse protection diode.
6.1.1.6
The charge status indicator, MODE, can be utilized to
illuminate an LED when the MCP73827 is in the con-
trolled current phase. When the MCP73827 transitions
to constant voltage mode, the MODE pin will transition
to a high impedance state. A current limit resistor
should be used in series with the LED to establish a
nominal LED bias current of 10 mA. The maximum
allowable sink current of the MODE pin is 30 mA.
6.2
For optimum voltage regulation, place the battery pack
as close as possible to the device’s V
pins. It is recommended to minimize voltage drops
along the high current carrying PCB traces.
If the PCB layout is used as a heatsink, adding many
vias around the external pass transistor can help con-
duct more heat to the back-plane of the PCB, thus
reducing the maximum junction temperature.
PCB Layout Issues
SHUTDOWN INTERFACE
CHARGE STATUS INTERFACE
MCP73827
DS21704B-page 13
BAT
and GND