1.0 Functional Description (Continued)
1.8.6 LOCAL AND REMOTE T_CRIT REGISTERS
(Read/Write):
D7
D6
D5
D4
D3
D2
D1
D0
MSB Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
LSB
D7–D0: RT_CRIT and LT_CRIT setpoint temperature data. Power up default is LT_CRIT =127˚C and RT_CRIT = 95˚C.
2.0 SMBus Timing Diagrams
20034310
(a) Serial Bus Write to the internal Command Register followed by a the Data Byte
20034311
(b) Serial Bus Write to the internal Command Register
20034312
(c) Serial Bus Read from a Register with the internal Command Register preset to desired value.
FIGURE 4. Serial Bus Timing Diagrams
path of best thermal conductivity is between the die and the
pins, its temperature will effectively be that of the printed
3.0 Application Hints
The LM91 can be applied easily in the same way as other
circuit board lands and traces soldered to the LM91’s pins.
integrated-circuit temperature sensors, and its remote diode
This presumes that the ambient air temperature is almost the
sensing capability allows it to be used in new ways as well.
same as the surface temperature of the printed circuit board;
It can be soldered to a printed circuit board, and because the
if the air temperature is much higher or lower than the
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