Linear Technology DC2028A Manual page 13

DEMO MANUAL DC2028A
ADvAnceD Demo BoArD operAtions
The log contains timestamp, up-time, channel voltage
readings, an input voltage reading, an on-chip temperature
reading, etc. There will be a number of loops; each loop
contains data obtained in one ADC loop time with the
most recent ADC loop data on top and the oldest data at
the bottom of the log. The up-time indicates, at the time
of fault, the amount of time the device had been powered
up or time since the previous reset.
In this case, the fault log will show that channel U0:7
faulted due to a VOUT_UV_FAULT condition. On the pre-
vious telemetry loop, the channel voltage reading was a
nominal value (3.3V).
To clear the fault log, click the Clear/Rearm EEPROM Log
button. This allows the selected device to be ready for a
new fault event. To clear all faults, click the clear faults
(CF) icon.
FAULT SHARING SETUP IN THE GUI
Fault sharing provides a means of propagating a fault detected by a power
manager to other power managers via FAULT pins. Use the Fault Sharing Setup
Tool to configure the fault sharing in the GUI. Select the LTC2977 in the system
tree. Go to Utilities > Fault Sharing Diagram. For more details on this topic,
please refer to the Fault Management section in the data sheet.
The fault sharing dialog will appear as shown in Figure 10. All
response and all propagate switches are closed by default. In this
configuration, a fault on a channel will shut down all LTC2977
channels, and a fault on any given channel will propagate to all
channels on the DC2028A demo board since the fault pins are
tied together.
NOTE: All FAULT pins of the LTC2977 are tied together on the
DC2028A demo board. These pins are open drain and have a
common pull-up resistor to provide a logic high level (inactive).
All FAULT pins are active low.
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Figure 10. Fault Sharing Utility in LTpowerPlay GUI
dc2028af