JAJSIO4A February 2020 – September 2020 TPS546A24A
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 Section 7.6.44. When Section 7.6.66 falls below Section 7.6.44, the overtemperature fault condition will be released and restart will be allowed if selected by Section 7.6.43. If Section 7.6.44 is programmed higher than Section 7.6.42, 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 Section 7.6.43 to any value outside those specified as valid will be considered invalid/unsupported data and cause the TPS546A24A 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 Section 7.6.43 OTF_RESP (Bits 7:6) are set to 11b - shut down until temperature is below Section 7.6.44, issuing a Section 7.6.4 command while the temperature is between Section 7.6.42 and Section 7.6.44 can result in the TPS546A24A remaining in the OT FAULT state until the temperature rises above Section 7.6.42 or disabled and enabled according to Section 7.6.3.
If Section 7.6.43 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 Section 7.6.42 greater than the maximum possible temperature during start-up.