MAX8671XETL+ Maxim Integrated Products, MAX8671XETL+ Datasheet - Page 31

• Manufacturer Part Number: MAX8671XETL+
• Description: IC PMIC W/CHARGER 40-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8671XETL+

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion), Lithium-Polymer (Li-Pol)
• Voltage - Supply: 4.1 V ~ 6.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 40-WFQFN Exposed Pad
• Mounting Style: SMD/SMT
• Input Voltage: 2.6 V to 6.6 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Output Current: 0.5 A
• Output Voltage: 0.6 V to 5 V
• Supply Current: 0.285 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 3. Charge Status Outputs
Note: CST1 and CST2 are active-low, open-drain outputs. “0”
indicates that the output device is pulling low. “1” indicates
that the output is high impedance.
As shown in Figure 7, a fault timer prevents the battery
from charging indefinitely. In prequalification and fast-
charge modes, the timer is controlled by the capaci-
tance at CT (C
C
and fast-charge times as follows (Table 4, Figure 8):
When the charger exits fast-charge mode, a fixed 15s
top-off mode is entered:
While in the constant-current fast-charge mode (Figure
6), if the MAX8671X reduces the battery charge current
due to its internal die temperature or large system
loads, it slows down the charge timer. This feature elim-
inates nuisance charge timer faults. When the battery
charge current is between 100% and 50% of its pro-
grammed fast-charge level, the fast-charge timer runs
at full speed. When the battery charge current is
between 50% and 20% of the programmed fast-charge
level, the fast-charge timer is slowed by 2x. Similarly,
when the battery charge current is below 20% of the
programmed fast-charge level, the fast-charge timer is
paused. The fast-charge timer is not slowed or paused
when the charger is in the constant voltage portion of
its fast-charge mode (Figure 6) where charge current
reduces normally.
CT
CST1
0
0
1
1
from 0.01µF to 1µF. Calculate the prequalification
Smart Power Selector for Handheld Devices
CST2
0
1
0
1
CT
). The MAX8671X supports values of
t
t
______________________________________________________________________________________
PQ
FC
=
=
CHARGING
660
33
t
TO
Yes
min
No
No
No
min
= 15
×
×
Charge Timer (CT)
0 15
s
PMIC with Integrated Charger and
0 15
C
.
C
.
CT
CT
μ
Thermistor suspend
μ
F
Prequalification or
No input power or
F
fast charge
Timer fault
top-off or
STATE
done
Connect CT to AGND to disable the prequalification
and fast-charge timers. With the internal timers of the
MAX8671X disabled, an external device, such as a µP,
can control the charge time through the CEN input.
As shown in Table 5 and Figure 9, a resistor from
CISET to ground (R
charge current (I
qualification mode (I
The MAX8671X supports values of I
200mA to 1000mA. Select the R
Table 4. Charge Times vs. C
Figure 8. Programming Charge Current
C
CT
100
150
220
470
68
(nF)
Setting the Charger Currents (CISET)
1000
100
10
1
t
PQ
0
R
103.4
15.0
22.0
33.0
48.4
CISET
(min)
vs. CHARGE SETTING RESISTOR
CHARGE, PREQUALIFICATION,
CHGMAX
AND TOP-OFF CURRENT
PQ
CISET
=
), and the top-off threshold (I
2000
5
100% to 50%
R
), the charge current in pre-
CISET
t
) sets the maximum fast-
FC
×
2068
299
440
660
968
(kΩ)
I
(min)
CHGMAX
CISET
1 5 .
10
I
V
CHGMAX
CT
I
I
TO
as follows:
PQ
CHGMAX
50% to 20%
15
t
FC
1320
1936
4136
598
880
(min)
from
TO
31
).