SC900841JVKR2 Freescale Semiconductor, SC900841JVKR2 Datasheet - Page 126

• Manufacturer Part Number: SC900841JVKR2
• Description: IC POWER MGT 338-MAPBGA
• Manufacturer: Freescale Semiconductor

Specifications of SC900841JVKR2

• Applications: PC's, PDA's
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 338-TBGA
• Input Voltage: 2.8 V to 4.4 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Supply: -
• Voltage - Supply: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

and the total trickle charge time has not expired. If the trickle
charge time expires before V
charger is turned off and the appropriate state is set. If V
rises above V
enter in the Quick Charge stage and I
charging. At any time during trickle charging, if a fault occurs,
the charger turns off and an interrupt is asserted, according
to the type of fault. The trickle charge time is always set to 1/
4 of the set t
the trickle charge mode. V
32 ms filter to debounce the transition between Trickle and
Quick Charge modes. Regardless of the timer state, if V
rises above V
asserted.
TRICKLE = 1. In this case, the full t
trickle charge. In this mode, charging stops if the timer
expires or V
trickle mode.
QUICK CHARGE
A soft transition between the trickle mode and the CC mode
is required to minimize the transient behavior at the input
WATCHDOG TIMER
Platform controller hub can enable and set for different times.
Setups and responses are highlighted in
NTC INTERFACE
value decreases over temperature (NTC). The NTC interface
allows an external NTC thermistor to monitor the battery
temperature and disable the charger when the temperature is
outside of a specific window. The relationship between
temperature T (in Kelvin) and the thermistor value (RT) is well
126
900841
FUNCTIONAL DEVICE OPERATION
BATTERY INTERFACE AND POWER PATH MANAGEMENT
Trickle charging can be forced as well, by setting the bit
The fast charge includes the CC mode and the CV mode.
The charger is equipped with a watchdog timer that the
A battery pack may be equipped with a thermistor which
BAT
CHG
TRKL
TRKL
exceeds V
timer. The t
, then the BATDET interrupt signal is
before the trickle charge time expires, we
Interrupt
V
COMP
I
CHGCV
TRKL
CHGCV
V
C HGCC
I
TRKL
TRKL
CHG
BAT
detection is equipped with a
timer is reset when entering
exceeding V
triggers the EOC on forced
Trickle
CHG
CHGCC
timer is used during
Figure
is used for
TRKL
63.
CC
, the
Figure 64. EOC Behavior
BAT
BAT
Current
Charge
I
C HGCOMP
during the transition. The Constant Current value (I
can be set by SPI programming the CHRGCC[2:0] bits, and
is regulated as explained previously. Once entering the CV
mode, the battery voltage is held at the battery float voltage
threshold V
CHRGCV[3:0] bits. The charge current reduces gradually
until the end of charge event EOC. The total charge time for
the quick charge is limited by t
mode.
threshold set by SPI programming the OVRVOLT[1:0] bits,
the buck charger is turned off and the BATOVP interrupt
signal is asserted.
END-OF-CHARGE (EOC)
are required to be simultaneously met: the battery voltage
must be above the recharge threshold V
charge current must fall below the EOC current I
I
CHRGCOMP[2:0] bits. A 1.0 ms filter is required to prevent
fast transient current, triggering the EOC current threshold.
characterized, and can be described as R
T
at T
slope of the thermistor over temperature. The NTC interface
can handle several standard B factors such as 3200, 3500,
and 3900.
up resistor R
V
NTC comparators, is controlled through the TEMPEN bit.
turned on automatically for battery temperature monitoring,
CHGCOMP
Quick
0
CORE
), with T
The t
If the battery voltage V
For a charge cycle to be completed (EOC), two conditions
To read out the thermistor value, it is biased through a pull-
During charging, the NTC comparators and the switch are
Voltage
Charge
0
, and B being the so called B-factor which indicates the
voltage to bias the chain. This switch, along with the
CHG
0
can be set by SPI programming the
CHGCV
CV
being room temperature, R
timer is reset when entering the fast charge
NTC
from the VNTC pin, which switches the
, which can be set by SPI programming the
Analog Integrated Circuit Device Data
BAT
exceeds the over-voltage
TIME
V
CHG
RCH G
.
Freescale Semiconductor
0
the thermistor value
RCHG
T
=R
0
, and the
*e^(B*(1/T – 1/
CHGCOMP
CHGCC
)
.