MAX8804Z Maxim Integrated Products, MAX8804Z Datasheet - Page 7

• Manufacturer Part Number: MAX8804Z
• Description: (MAX8804Y/Z) USB/AC Adapter Chargers
• Manufacturer: Maxim Integrated Products

Figure 1. Functional Diagram
The MAX8804Y/MAX8804Z dual-input linear battery
chargers use voltage, current, and thermal-control loops
to charge and protect a single Li+ battery. When a Li+
battery with a cell voltage below 2.5V is inserted, the
MAX8804Z charger enters the prequalification stage
where it precharges that cell with 95mA (Figure 2). The
CHG indicator output is driven low to indicate entry into
the prequalification state. When battery voltage exceeds
2.5V, the charger soft-starts as it enters the fast-charge
stage. The MAX8804Y eliminates the prequalification
state and enters fast-charge when the battery is inserted.
In the MAX8804Y/MAX8804Z, the fast-charge current
4.15V TO 30V
4.15V TO 16V
USB
_______________________________________________________________________________________
DC
Adapter Chargers in 2mm x 3mm TDFN
Detailed Description
REF
POK
USB
POK
DC
High-Voltage, Dual-Input, USB/AC
MAX8804Y
MAX8804Z
CIRCUIT
BIAS
DC AND USB OUTPUT CONTROL
CONTROL
LOGIC
GND
VOLTAGE
LOOP
level is programmed by a simple single-wire interface.
As the battery voltage approaches 4.2V, the charging
current is reduced. If the battery current drops below the
top-off current threshold, the CHG indicator goes high
impedance, signaling that the battery is fully charged.
The ICs then enter a constant voltage-regulation mode to
maintain the battery at full charge.
The MAX8804Y/MAX8804Z automatically select between
either a USB or AC adapter input source. The AC
adapter charge current is programmable from 400mA to
700mA in 50mA steps through a simple single-wire inter-
face. The USB charge current is programmable to 95mA,
380mA, or 475mA through the same interface.
OVERVOLTAGE
PROTECTION
+105°C
SENSOR
TEMP
USBPWR
SET
CHG
POK
BAT
Li+
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