MAX8819BETI+T Maxim Integrated Products, MAX8819BETI+T Datasheet - Page 19

• Manufacturer Part Number: MAX8819BETI+T
• Description: IC PMIC W/INT CHARGER 28-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8819BETI+T

• Applications: Handheld/Mobile Devices
• Voltage - Supply: 2.6 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Supply: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

• The battery charger is enabled by the processor dri-
• The system current has priority over the battery
• The input current limit is tapered down from full cur-
• The battery charger stops charging in done mode
CHG is an open-drain, active-low output that indicates
charger status. As shown in Figures 2 and 3, CHG is
low when the charger is in its prequalification or fast-
charge states. When a timer count is exceeded in
either state, CHG indicates the fault by blinking at a
2Hz rate and remains in that state until the charger is
reset by CEN going low, removal of DC or setting
DLIM[1:2] = 11.
When the MAX8819_ is used with a microprocessor
(μP), connect a pullup resistor between CHG and the
system logic voltage to indicate charge status to the
μP. Alternatively, CHG sinks up to 20mA for an LED
charge indicator.
If the charge status output feature is not required, con-
nect CHG to ground or leave unconnected.
As shown in Figure 3, a fault timer prevents the battery
from charging indefinitely. In prequalification mode, the
charge time is internally fixed to 33min.
In fast-charge mode, the charge timer is internally fixed
to 660min.
When the charger exits fast-charge mode, a fixed
33min top-off mode is entered:
While in the constant-current fast-charge mode (Figure
2), if the MAX8819_ reduces the battery charge current
due to its internal die temperature or large system loads,
it slows down the charge timer. This feature eliminates
ving the CEN input high. A valid input must be avail-
able at DC. The battery charger is disabled without
a valid input at DC or by driving CEN low.
charger; the battery charger automatically reduces
its charge current to maintain the input current limit
while still providing the system current (I
rent to zero current when the die temperature transi-
tions from +100°C to +120°C. Since I
over the battery charge current, the battery charge
current tapers down before I
self-regulation of die temperature (see the Thermal
Limiting and Overload Protection section for more
information).
as shown in Figures 2 and 3.
PMIC with Integrated Chargers and Smart
______________________________________________________________________________________
t
t
PREQUAL
FSTCHG
t
TOPOFF
Power Selector in a 4mm x 4mm TQFN
Charge Status Output (CHG)
= 660min
= 33min
= 33min
SYS
. The overall result is
SYS
Charge Timer
SYS
has priority
).
nuisance charge timer faults. When the battery charge
current is between 100% and 50% of its programmed
fast-charge level, the fast-charge timer runs at full
speed. When the battery charge current is between
50% and 20% programmed fast-charge level, the fast-
charge timer is slowed by 2x. Similarly, when the bat-
tery 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 2) where the charge current
reduces normally.
Figure 4. Calculated Charge Currents vs. R
Table 2. Calculated Charge Currents vs.
R
R
CISET
CISET
3.01
4.02
4.99
6.04
6.98
8.06
9.09
12.1
10
11
13
14
15
(kΩ)
10,000
FAST-CHARGE, PREQUALIFICATION, AND TOP-OFF
1000
100
10
1
CURRENT vs. CHARGE-SETTING RESISTOR
0
I
PREQUAL,
I
CHGMAX
(mA)
1000
746
601
497
430
372
330
300
273
248
231
214
200
5
I
TOPOFF
I
CHGMAX
R
CISET
10
(kΩ)
I
PREQUAL
(mA)
100
75
60
50
43
37
33
30
27
25
23
21
20
15
CISET
20
I
TOPOFF
(mA)
100
75
60
50
43
37
33
30
27
25
23
21
20
19