MAX8808 MAXIM [Maxim Integrated Products], MAX8808 Datasheet - Page 9

• Manufacturer Part Number: MAX8808
• Description: 1A Linear Li+ Battery Chargers with Integrated Pass FET and Thermal Regulation in 2mm x 2mm TDFN
• Manufacturer: MAXIM [Maxim Integrated Products]

The MAX8808X/MAX8808Y/MAX8808Z operate from
well-regulated DC sources. The full charging input volt-
age range is 4.25V to 7V. The device can withstand up
to 15V on the input without damage to the IC. If V
Figure
Figure
1A Linear Li+ Battery Chargers with Integrated Pass
4.25V TO 15V
ENABLE
INPUT
2.8kΩ
FET and Thermal Regulation in 2mm x 2mm TDFN
1µF
C1
3. Stand-Alone Li+ Battery Charger
4. µP-Interfaced Li+ Battery Charger
R1
ADAPTER
AC/DC
IN
EN (EN)
ISET
(MAX8808Y)
_______________________________________________________________________________________
MAX8808X
MAX8808Z
GND
0.47µF
2.8kΩ
ACOK
BATT
C3
CHG
R1
1µF
VL
C1
V
LOW: CHARGE, HIGH: FULL OR OFF
I/O
DC Input Sources
R2
510Ω
C2
1µF
C3
0.47µF
IN
CHG
VL
ISET
CHARGE-CURRENT MONITOR
4.2V
Li+
MAX8808XETA
R3
100kΩ
AC-INPUT
PRESENT
INDICATOR
IN
is
ACOK
BATT
GND
100kΩ
EN
R4
greater than 7V, the internal overvoltage-protection cir-
cuitry disables charging until the input falls below 7V.
An appropriate power supply must provide at least
4.25V at the desired peak charging current. It also must
stay below 6.5V when unloaded.
The MAX8808X/MAX8808Y/MAX8808Z provide a com-
plete Li+ charging solution.
alone Li+ battery charger. The 2.8kΩ resistor
connected to ISET sets a charging current of 465mA.
The LED connected to the CHG output indicates when
either fast-charge or precharge qualification has
begun. When the battery is full, CHG turns high imped-
ance and the LED turns off.
Figure
battery charger. The MAX8808X begins charging the bat-
tery when EN is low. The µP can drive EN high to disable
the charger. The MAX8808X generates a ACOK signal to
indicate the presence of an input supply. CHG is used to
detect the charge status of the battery. By monitoring
V
ISET
V
I/O
, the system can measure the charging current.
C2
1µF
4 shows the MAX8808X as a µP co-operated Li+
10kΩ
R2
4.2V
Li+
100kΩ
Microprocessor-Interfaced Charger
R3
V
0.1µF
I/O
C4
Stand-Alone Li+ Charger
Application Circuits
Figure
SYSTEM
3 shows a stand-
9