7.5.34 STATUS_BYTE (78h)
The STATUS_BYTE command returns one byte of information with a summary of the most critical device faults.
| COMMAND |
STATUS_BYTE |
| Format |
Unsigned binary |
| Bit Position |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| Access |
r |
r |
r |
r |
r |
r |
r |
r |
| Function |
X |
OFF |
OVF |
OCF |
X |
OTFW |
CML |
oth |
| Default Value |
0 |
X |
0 |
0 |
0 |
0 |
0 |
1 |
A 1 in any of these bit positions indicates that:
OFF The device is not providing power to the output, regardless of the reason. In this family of devices, this flag means that the converter is not enabled.
OVF An output overvoltage fault has occurred. This bit directly reflects the state of STATUS_VOUT[7] – OVF. If the user wants this fault source to be masked and not trigger SMBALERT, they must do it by masking STATUS_VOUT[7]. Per the PMBus v1.3 spec sections 10.2.4 and 10.2.5, this bit is not clearable through a PMBus write. In contrast, the bit is to be cleared by clearing the bits in STATUS_VOUT that cause this bit to be set. For loop slave device, this bit is 0.
OCF An output overcurrent fault has occurred. This bit directly reflect the state of STATUS_IOUT[7] – OCF. If the user wants this fault sourced to be masked and not trigger SMBALERT, they must do it by masking STATUS_IOUT[7]. Per the PMBus v1.3 spec sections 10.2.4 and 10.2.5, this bit is not clearable through a PMBus write. In contrast, the bit is to be cleared by clearing the bits in STATUS_IOUT that cause this bit to be set.
OTFW A temperature fault or warning has occurred. Check STATUS_TEMPERATURE. Per the PMBus v1.3 spec sections 10.2.4 and 10.2.5, this bit is not clearable through a PMBus write. In contrast, the bit is to be cleared by clearing the bits in STATUS_TEMPERATURE that cause this bit to be set.
CML A communications, memory or logic fault has occurred. Check STATUS_CML. Per the PMBus v1.3 spec sections 10.2.4 and 10.2.5, this bit is not clearable through a PMBus write. In contrast, the bit is to be cleared by clearing the bits in STATUS_CML that cause this bit to be set.
oth A fault or warning not listed through bits 1-7 has occurred, which include an undervoltage fault, over current warning, overvotlge warning, undervoltage warning, TON_MAX_FAULT, LOW_VIN, VOUT_MAX_MIN_Warning, OTF_BG, or IV_PPV1. Check other status registers. Per the PMBus v1.3 spec sections 10.2.4 and 10.2.5, this bit is not clearable through a PMBus write. In contrast, the bit is to be cleared by clearing the bits in STATUS_VOUT, STATUS_IOUT, STATUS_IOUT (7Bh), or STATUS_MFR_SPECIFIC (80h)that cause this bit to be set. The default for this bit is 1 because the default of STATUS_INPUT[3] LOW_Vin defaulting to 1.