MAX8845XETC+ Maxim Integrated Products, MAX8845XETC+ Datasheet - Page 7

• Manufacturer Part Number: MAX8845XETC+
• Description: IC BATT CHARGER CCCV 28V 12TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8845XETC+

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion)
• Voltage - Supply: 0 V ~ 28 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 12-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W
chargers use voltage, current, and thermal-control
loops to charge a single Li+ cell and protect the battery
(Figure 1). When a Li+ battery with a cell voltage below
2.5V is inserted, the MAX8845Z/MAX8845Y/MAX8845X/
MAX8845W chargers enter a prequalification stage
where it precharges that cell with 10% of the user-pro-
Figure 1. MAX8845Z/MAX8845Y/MAX8845X/MAX8845W Functional Diagram
28V Linear Li+ Battery Chargers with Battery
SETI
MIN
Detection and Overvoltage Protected Output
IN
OVLO
V
IN
IN
DETBAT
BATT
_______________________________________________________________________________________
MAX8845W
MAX8845Z
MAX8845Y
MAX8845X
Detailed Description
REGULATOR
WITH OVP
LINEAR
I
MINREF
UVLO
VL
V
REF
REGULATOR
VL
GND
REFOK
REF
CURRENT SENSE,
OUTPUT DRIVER,
V
V
REF
AND LOGIC
L
EP
LOGIC
grammed fast-charge current (Figure 2). The CHG indi-
cator is driven low to indicate entry into the prequalifi-
cation state. When the battery voltage exceeds 2.5V,
the charger soft-starts as it enters the fast-charge
stage. The fast-charge current level is programmed
through a resistor from SETI to GND. As the battery
voltage approaches 4.2V, the charging current is
reduced. If the battery current drops to less than the
V
REF
POK
+115°C
TEMPERATURE
SENSOR
200kΩ
200kΩ
BATT
ABO (MAX8845Y/MAX8845X/MAX8845W)
EN
SAFEOUT
CHG
POK
ABO (MAX8845Z ONLY)
ABI
BATT
DETBAT
V
I/O
MAX8845W ONLY)
(4.35V FOR
4.2V Li+
7