Vicor PI33XX-2X I2C Digital Interface Guide - Manual (Page 8)

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PI33XX-2X I
2
C Digital Interface Guide
MRGN[3:0] % V(OUT)
1100 -20
1101 -15
1110 -10
1111 -5
0000 0
1000 +5
1001 +10
1010 +15
1011 +20
Table 4 - PI33XX-2X Margin Register Assignments
Fault Telemetry Command Structure
The PI33XX-2X command structure is always a 2 byte write and a 1 byte read following the start condition and the
base address when using Picor Buck GUI and the LinkM interface. The second data byte is either 00h or additional
data based on the command being sent. Figure 5 is an example of an I
2
C bus command to read the fault register
and it can be implemented using the Picor Buck GUI by left clicking the “FAULT” button. In a similar fashion, the
actual fault register can be read from a generic I
2 C device as shown in Figure 6 by sending the commands shown
followed by stop bits. The I
2
C device used for sending the command required a R/W bit for addressing so the
address of 4Ch was sent as 98h.
Figure 5 - Fault Register Read No Fault
In figure 5, the address of 4Ch was sent followed by the first data byte. “4Ch” represents the base address of the
PI33XX-2X as determined by ADR0 and ADR1. The first data byte is the address decode of the internal register to
be read (or written); in this case, read. “1Ah” is address of the fault register as shown in Table 2.