MAX8934BETI+T Maxim Integrated Products, MAX8934BETI+T Datasheet - Page 22

• Manufacturer Part Number: MAX8934BETI+T
• Description: IC BATTERY CHARGER DUAL 28TQFN
• Manufacturer: Maxim Integrated Products
• Series: Smart Power Selector™r

Specifications of MAX8934BETI+T

• 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: 28-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Dual-Input Linear Chargers, Smart Power Selector
with Advanced Battery Temperature Monitoring
Table 2b. Input Limiter Control Logic (MAX8934D)
wire-ORed together. The combined output then pulls low
if either USB or DC is valid.
To prevent input transients that can cause instability in
the USB or AC adapter power source, the rate of change
of input current and charge current is limited. When a
valid DC or USB input is connected, the input current
limit is ramped from zero to the set current-limit value
(as shown in Tables 2a and 2b). If DC is connected with
no USB power present, input current ramps in 1.5ms. If
DC is connected with USB already present, input current
ramps in 50Fs. When USB is connected with no DC pres-
ent, input current also ramps in 50Fs. If USB is connect-
ed with DC already present, the USB input is ignored.
If an adapter is plugged into DC while USB is already
powered, the input current limit reramps from zero back
up to the DC current limit so that the AC adapter does
not see a load step. During this transition, if the input
current limit is below the SYS load current, the battery
supplies the additional current needed to support the
load. Additionally, capacitance can be added to SYS to
22
Absolute Maximum Rating
Input Current Limit
AC Adapter
USB Power
USB Power
USB Open
SOURCE
DC Open
POWER
at USB;
DC and
at DC
at DC
_____________________________________________________________________________________
FEATURE
DOK
H
H
H
H
H
H
L
L
L
L
L
Set by R
UOK
X
X
X
X
X
H
L
L
L
L
L
PSET
DC INPUT
2A (max)
USUS;
, PEN1, PEN2, and
16V
PEN1
H
H
H
H
Soft-Start
L
L
L
L
L
X
X
PEN2
X
X
H
X
H
H
X
X
L
L
L
support the load during input power transitions. When
the charger is turned on, charge current ramps from
zero to the ISET current value in typically 1.5ms. Charge
current also ramps when transitioning to fast-charge
from prequal and when changing the USB charge cur-
rent from 100mA to 500mA with PEN2. There is no dI/dt
limiting, however, if ISET is changed suddenly using a
switch at R
The battery charger state diagram is illustrated in Figure
8. With a valid DC or USB input, the battery charger
initiates a charge cycle when the charger is enabled. It
first detects the battery voltage. If the battery voltage is
less than the BATT prequal threshold (3.0V), the charger
enters prequal mode and charges the battery at 10% of
the maximum fast-charge current. This reduced charge
rate ensures that the maximum fast-charge current set-
ting does not damage a deeply discharged battery.
Once the battery voltage rises to 3.0V, the charger tran-
sitions to fast-charge mode and applies the maximum
charge current. As charging continues, the battery volt-
age rises until it approaches the battery regulation volt-
USUS
Set by R
X
X
H
H
X
L
L
L
L
L
L
PEN2, and USUS;
USB INPUT
1.5A (max)
ISET
PSET
9V
USB suspend
3000V/R
3000V/R
No DC input
CURRENT
DC INPUT
475mA
.
LIMIT
95mA
, PEN1,
PSET
PSET
USB suspend
No USB input
Off; DC input
3000V/R
USB INPUT
600V/R
current limit for DC and USB
has priority
CURRENT
USB Input
PSET sets the same input
475mA
LIMIT
95mA
PSET
PSET
Battery Charger
NOTES
paths.
—
3000V/R
3000V/R
3000V/R
3000V/R
MAXIMUM
CURRENT
CHARGE
475mA
475mA
95mA
95mA
0
0
0
ISET
ISET
ISET
ISET