MAX16070 Datasheet, PDF (43/52 Pages) Maxim Integrated Products – 12-Channel/8-Channel, Flash-Configurable System Monitors with Nonvolatile Fault Registers

12-Channel/8-Channel, Flash-Configurable System
Managers with Nonvolatile Fault Registers
Configuring the Device
An evaluation kit and a graphical user interface (GUI) is
available to create a custom configuration for the device.
Refer to the MAX16070/MAX16071 evaluation kit for con-
figuration.
Cascading Multiple MAX16070/MAX16071s
Multiple MAX16070/MAX16071s can be cascaded to
increase the number of monitored rails. There are many
ways to cascade the devices depending on the desired
behavior. In general, there are several techniques:
U Configure a GPIO_ on each device to be EXTFAULT
(open drain). Externally wire them together with a
single pullup resistor. Set register bits r72h[5] and
r6Dh[2] to ‘1’ so that all faults will propagate between
devices. If a critical fault occurs on one device,
EXTFAULT will assert, triggering the nonvolatile fault
logger in all cascaded devices and recording a snap-
shot of all system voltages.
U Connect open-drain RESET outputs together to obtain
a master system reset signal.
U Connect all EN inputs together for a master enable
signal.
Monitoring Current Using
the Differential Inputs
The MAX16070/MAX16071 can monitor up to seven
currents using the dedicated current-sense amplifier as
well as up to six pairs of inputs configured in differential
mode. The accuracy of the differential pairs is limited by
the voltage range and the 10-bit conversions. Each input
pair uses an odd-numbered MON_ input in combination
with an even-numbered MON_ input to monitor both the
voltage from the odd-numbered MON_ to ground and
the voltage difference between the two MON_ inputs.
This way a single pair of inputs can monitor the voltage
and the current of a power-supply rail. The overvoltage
threshold on the even numbered MON_ input can be
used as an overcurrent flag.
POWER
SUPPLY
R_S
I_LOAD
MON_ODD
MON_EVEN
MAX16070
MAX16071
Figure 16. Current Monitoring Connection
Figure 16 shows how to connect a current-sense resis-
tor to a pair of MON_ inputs for monitoring both current
and voltage.
For best accuracy, set the voltage range on the even-
numbered MON_ to 1.4V. Since the ADC conversion
results are 10 bits, the monitoring precision is 1.4V/1024
= 1.4mV. For more accurate current measurements,
use larger current-sense resistors. The application
requirements should determine the balance between
accuracy and voltage drop across the current-sense
resistor.
Layout and Bypassing
Bypass DBP and ABP each with a 1FF ceramic capacitor
to GND. Bypass VCC with a 10FF capacitor to ground.
Avoid routing digital return currents through a sensitive
analog area, such as an analog supply input return path
or ABP’s bypass capacitor ground connection. Use
dedicated analog and digital ground planes. Connect
the capacitors as close as possible to the device.
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