MAX8804 MAXIM [Maxim Integrated Products], MAX8804 Datasheet - Page 14

• Manufacturer Part Number: MAX8804
• Description: High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN
• Manufacturer: MAXIM [Maxim Integrated Products]

where R
0.55Ω for DC or 0.65Ω for USB). Failure to meet this
requirement results in an incomplete charge or
increased charge time.
The MAX8804V/MAX8804W/MAX8804Y/MAX8804Z pro-
vide a complete Li+ charging solution. The Typical
Application Circuit shows the MAX8804V/MAX8804W/
MAX8804Y/MAX8804Z as a stand-alone Li+ battery
charger. The LED indicates when either fast-charge or
prequalification has begun. When the battery is fully
charged, the LED turns off.
High-Voltage, Dual-Input, USB/AC
Adapter Chargers in 2mm x 3mm TDFN
Figure 5. Microprocessor-Interfaced Li+ Charger with the MAX8804V/MAX8804W/MAX8804Y/MAX8804Z
14
______________________________________________________________________________________
V
ON
IN(MIN)
is the input-to-BAT resistance (typically
> 4.2V + I
USB PORT
ADAPTER
AC
Li+
CHARGE(MAX)
Stand-Alone Li+ Charger
Application Circuits
2.2μF
1μF
1μF
x R
ON
USB
DC
(DETBAT)
BAT
MAX8804W
MAX8804V
MAX8804Y
MAX8804Z
GND
<USBPWR>
Figure 5 shows the MAX8804V/MAX8804W/MAX8804Y/
MAX8804Z as a µP-interfaced Li+ battery charger. The
µP drives SET to enable/disable DC/USB mode charg-
ing. CHG can be used to detect the charge status of a
battery.
Connect the input capacitors as close as possible to
the IC. Provide a large copper GND plane to allow the
exposed paddle to sink heat away from the IC. Connect
the battery to BAT as close as possible to the IC to pro-
vide accurate battery voltage sensing. Make all high-
current traces short and wide to minimize voltage
drops. A sample layout is available in the MAX8804Z
evaluation kit to speed designs.
CHG
POK
SET
SYSTEM I/O
Microprocessor-Interfaced Li+ Charger
NOTE: ( ) FOR MAX8804V/MAX8804W
< > FOR MAX8804Y/MAX8804Z
Layout and Bypassing
μP