SLUSF27 November 2023 TPS546B24S
PRODUCTION DATA
| CMD Address | 50h |
| Write Transaction: | Write Byte |
| Read Transaction: | Read Byte |
| Format: | Unsigned Binary (1 byte) |
| Phased: | No |
| NVM Back-up: | EEPROM |
| Updates: | On-the-fly |
The OT_FAULT_RESPONSE command instructs the device on what action to take in response to an Overtemperature Fault. Upon triggering the overtemperature fault, the converter responds per the data byte below, and the following actions are taken:
Note: the OT Fault hysteresis is set by the (51h) OT_WARN_LIMIT. When (8Dh) READ_TEMPERATURE_1 falls below (51h) OT_WARN_LIMIT, the overtemperature fault condition will be released and restart will be allowed if selected by (50h) OT_FAULT_RESPONSE. If (51h) OT_WARN_LIMIT is programmed higher than (4Fh) OT_FAULT_LIMIT, a default hysteresis of 20°C will be used instead.
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| RW | RW | RW | RW | RW | RW | RW | RW |
| OTF_RESP | OT_RETRY | OT_DELAY | |||||
| LEGEND: R/W = Read/Write; R = Read only |
| Bit | Field | Access | Reset | Description |
|---|---|---|---|---|
| 7:6 | OTF_RESP | RW | NVM | Overtemperature fault response 00b: Ignore. Continue operating without interruption. 01b: Delayed Shutdown Continue Operating for 10ms x OT_DELAY. If OT_FAULT is still present, shut down and restart according to OT_RETRY. 10b: Immediate Shutdown. Shut down and restart according to OT_RETRY. 11b: Shutdown until Temperature is below OT_WARN_LIMIT, then restart according to OT_RETRY*. |
| 5:3 | OT_RETRY | RW | NVM | Overtemperature retry 0d: Do not attempt to restart (latch off). 1d-6d: After shutting down, wait one HICCUP period, and attempt to restart up to 1 - 6 times. After 1 - 6 failed restart attempts, do not attempt to restart (latch off). Restart attempts that occur while temperature is above OT_WARN_LIMIT will not be observable but will be counted. 7d: After shutting down, wait one HICCUP period, and attempt to restart indefinitely, until commanded OFF or a successful start-up occurs. |
| 2:0 | OT_DELAY | RW | NVM | Overtemperature delay time for respond after delay and HICCUP 0d: Shutdown delay of 0 ms, HICCUP equal to TON_RISE, HICCUP delay equal to TON_RISE 1d - 7d: Shutdown delay of 10-70 ms, HICCUP equal to 1 - 7 times TON_RISE |
Attempts to write (50h) OT_FAULT_RESPONSE to any value outside those specified as valid will be considered invalid/unsupported data and cause the TPS546B24S to respond by flagging the appropriate status bits and notifying the host according to the PMBus 1.3.1 Part II specification section 10.9.3.
*When (50h) OT_FAULT_RESPONSE OTF_RESP (Bits 7:6) are set to 11b - shut down until temperature is below (51h) OT_WARN_LIMIT, issuing a (03h) CLEAR_FAULTS command while the temperature is between (4Fh) OT_FAULT_LIMIT and (51h) OT_WARN_LIMIT can result in the TPS546B24S remaining in the OT FAULT state until the temperature rises above (4Fh) OT_FAULT_LIMIT or disabled and enabled according to (02h) ON_OFF_CONFIG.
If (50h) OT_FAULT_RESPONSE is configured to ignore a OT_FAULT, and a OT_FAULT is present at the time of enabling the device, the device will not start up. To ensure the part will ignore any potential OT_FAULT at start-up, it is recommended to set the (4Fh) OT_FAULT_LIMIT greater than the maximum possible temperature during start-up.