JAJSHZ0A April 2013 – September 2019 TMP108
PRODUCTION DATA.
In comparator mode (TM = 0), the ALERT pin becomes active when the temperature exceeds the value in the THIGH register or drops below the value in the TLOW register. The ALERT pin remains active until the temperature returns to a value that is within the range set by:
where
In interrupt mode (TM = 1), the ALERT pin becomes active when the temperature exceeds the value in the THIGH register or drops below the value in the TLOW register, and remains active until a read operation of the configuration register occurs (also clears the values latched in the watchdog flags, FL and FH), or the device successfully responds to the SMBus alert response address. The ALERT pin is also cleared by resetting the device with the general call reset command.
Both operational modes are represented in Figure 13 and Figure 14.
Table 11 and Table 12 describe the format for the THIGH and TLOW registers. Note that the most significant byte is sent first, followed by the least significant byte. Power-up (reset) default values are THIGH = +127.9375°C (0x7FF8) and TLOW = –128°C (0x8000). These values ensure that upon power-up, the limit window is set to maximum, and the ALERT pin does not become active until the desired limit values are programmed in the registers. Other default values for the temperature limits are available by request. The format of the data for THIGH and TLOW is the same as for the temperature register.
BYTE | D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 |
---|---|---|---|---|---|---|---|---|
1 | H11 | H10 | H9 | H8 | H7 | H6 | H5 | H4 |
BYTE | D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 |
2 | H3 | H2 | H1 | H0 | 0 | 0 | 0 | 0 |
BYTE | D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 |
---|---|---|---|---|---|---|---|---|
1 | L11 | L10 | L9 | L8 | L7 | L6 | L5 | L4 |
BYTE | D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 |
2 | L3 | L2 | L1 | L0 | 0 | 0 | 0 | 0 |