MAX11068EVKIT+ Maxim Integrated Products, MAX11068EVKIT+ Datasheet - Page 27

• Manufacturer Part Number: MAX11068EVKIT+
• Description: KIT SMART BATT MEASUREMENT 12CH
• Manufacturer: Maxim Integrated Products

Specifications of MAX11068EVKIT+

• Main Purpose: Power Management, Battery Monitor, Car
• Utilized Ic / Part: MAX11068
• Primary Attributes: Monitors Current, Voltage, Temperature
• Secondary Attributes: 1 ~ 12 Cell- Li-Ion, 1 ~ 12 Cell- NiMH
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Embedded: -

for a hot-swap insertion of the battery cells. Once the
POR threshold is reached, the internal RESET signal
disables. A status bit, RSTSTAT in the STATUS register
(address 0x02), is set when power is restored to the
digital logic following a reset event to denote that a reset
has occurred. It should be checked and cleared by the
system controller so that any future reset condition can
be resolved. Figure 19 is the internal low-dropout regula-
tor block diagram.
The MAX11068 power-up sequence is shown in Figure
20. Starting with no DC power applied, the device waits
for a power source and then waits until the SHDN signal
is deactivated. If the internal die temperature limit is
not exceeded, the regulator is enabled. The regulator
begins to regulate the DCIN input voltage down to 3.3V.
After VAA has reached the rising POR threshold, the
internal POR signal is deasserted and the various sec-
tions of the device begin to initialize, starting with the
32kHz oscillator. An additional 280Fs after the oscillator
becomes active, the digital logic becomes active and
the charge pump begins operating. The charge pump
reaches full regulation in approximately 3ms depending
on the external circuit components used, at which time
the MAX11068 is ready for operation. When the charge
pump achieves regulation of 3.4V between VDD
Figure 19. Internal Low-Dropout Regulator Block Diagram
12-Channel, High-Voltage Sensor, Smart
SHDN
DCIN
DIE OVERTEMP
DETECT
THRESHOLD
+6.0V TO +72V
POR
REGULATOR
ENABLE
+3.0V
REFERENCE
±5%
BANDGAP
REGULATOR
LINEAR
POWER-ON RESET
COMPARATOR
U
and
Data-Acquisition Interface
CHARGE-PUMP
+
-
GND
drops by 20mV to minimize operation during light load-
ing. The specification accuracies and full operation of
the MAX11068 are not guaranteed until a minimum of
6.0V is applied to the DCIN pin. The regulator has built-in
short-circuit protection in case of a fault condition. Figure
21 shows asynchronous regulator disable events and
Figure 22 shows the POR event sequence.
The regulator incorporates a thermal-shutdown feature.
If the MAX11068 die temperature rises above +145NC,
the device shuts down by disabling the internal regula-
tor. The cell-balancing switches are also independently
disabled in case an external power source maintains
power to the digital logic through VDD
of the BALCFG register are not directly altered by the
overtemperature condition, but unless VDD
from a source other than VAA, the POR event caused
by the regulator shutting down resets all registers to
their default values. After a thermal shutdown event, the
die temperature must cool 15NC below the shutdown
temperature before the device reenables the regulator.
Figure 23 shows a more detailed view of the charge
pump and the supply and ground references for the
regulator and charge pump. The charge pump is driven
by a 4mA current source, I
INTERNAL +3.4V
ENABLE
U
, it switches to a standby mode until the voltage
CHARGE
PUMP
HYSTERESIS
20mV
-
+
INTERNAL
POR
PUMP
+3.4V
GND
TO
VAA
GND
VDD
U
U
U
.
L
. The settings
L
is supplied
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