MAX11068EVKIT+ Maxim Integrated Products, MAX11068EVKIT+ Datasheet - Page 69

• 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: -

Figure 43. Example WRITEALL Bit Stream Prior to PEC Transmission
A VAA voltage below the POR threshold results in an
internal device reset. In this state, the charge pump is
disabled, as well as the digital logic. Therefore, after
VAA and VDD
reset levels, I
forwarded. In some cases, a parasitic power path may
exist to VDD
cation pullup resistors or logic signals from the host.
These paths typically supply VDD
below the pullup level. As long as the pullup level is no
more than one diode drop above the POR threshold, the
entire device, including the digital logic remains in reset.
Supplying VAA or VDD
the reset threshold can result in active operation, even
though the regulator may be disabled. When the POR is
not active and VDD
tion proceeds as normal.
The MAX11068 offers a comprehensive system to inform
the host controller of the device’s status. This is done
with status alerts and status alarms. Status alerts are flag
bits reporting various monitoring functions of the device.
Alerts can be divided into three main groups. Cell moni-
toring alerts are flags that report conditions related to the
cell measurement. They include:
U Cell undervoltage threshold crossed (UVTHRSET)
U Cell overvoltage threshold crossed (OVTHRSET)
U Cell voltage mismatch threshold crossed (MSMTCH)
U Auxiliary channel temperature measurement thresh-
The second group of alert flags are communication
errors. These flags report conditions related to the func-
tioning of the SMBus ladder. They include:
old crossed (AINOT, AINUT)
L
Alert and Alarm Status Functions
2
, and therefore VAA, through communi-
C communication is ignored and is not
U
I
2
HOST TO IC1
have decayed below the power-on
12-Channel, High-Voltage Sensor, Smart
C BUS LINK
Power-On-Reset (POR) Event
U
and VDD
L
with a power source above
I
2
S
C BUS FORWARDING DATA STREAM
L
are valid, communica-
01000000
L
BIT STREAM FOR PEC EXAMPLE CALCULATION
at one diode drop
A
00001001
Data-Acquisition Interface
A
U Packet error checking (ALRTPEC)
U Acknowledge error (ALRTACK)
The last group of alerts report operational failures of
blocks of the IC. These flags aid in detecting conditions
that signal if the device is operating correctly. They
include:
U Reset status (RSTSTAT)
U Charge-pump failure (ALRTCPUV)
U Heartbeat signal out of specification (ALRTHBEAT)
U Voltage reference failure (ALRTREF)
U Lower +3.3V supply failure (ALRTVDDL)
U Lower GND failure (ALRTGNDL)
These alerts are activated when the configured thresh-
olds are violated for a particular monitored condition or
a particular function did not execute as expected. Status
alerts are indicated by individual flag bits in various reg-
isters and must be read through the communication bus
and processed by the host controller.
Status alarms are indicated using the alarm ladder bus
comprising the ALRM
the result of an active alert that has been enabled to
trigger an alarm. By monitoring the alarm bus with the
system controller, the controller has nearly instant vis-
ibility of critical status conditions. Normally, this alarm
bus carries a 16.384kHz heartbeat signal from the top
device in the SMBus ladder to the bottom device. When
an alarm is activated in a device, the alarming device
pulls the alarm bus to logic high and interrupts the flow
of the heartbeat signal. In this way, the alarm function
acts as a high-priority interrupt signal to the host control-
ler for critical events.
11111111
A
00000011
L
and ALRM
A
U
ports. An alarm is
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