1°C Triple Temperature Sensor with Hotter of Two Zones
Datasheet
The External Diode 1 channel has the REC functionality disabled for use in monitoring an AMD K8
processor. The External Diode 2 channel defaults to REC functionality disabled but can be enabled by
writing to the Configuration 2 Register (see Section 4.5). If the External Diode 2 channel is connected
as a diode-connected transistor as shown in Figure 3.3, resistance error correction should be enabled
to minimize series resistance and improve accuracy
3.7
Programmable Ideality Factor
The EMC1063 default is for a diode ideality factor of 1.008 which is common for a 2N3904 diode and
for many processor transistors. When a diode or transistor is used that has a different ideality factor
value than 1.008 a temperature error is induced that is a linear function of temperature. Previous
solutions for this mismatch in ideality factor has been to supply a programmable offset to the
temperature reading which corrects the error at a single temperature but causes a residual error at all
other temperatures. The EMC1063 ideality factor register corrects this mismatch error at all
temperatures (see Section 4.7).
APPLICATION NOTE: When monitoring a substrate transistor or CPU diode and beta compensation is enabled, the
Ideality Factor should not be adjusted. Beta Compensation automatically corrects for most
ideality errors.
3.8
Diode Faults
The EMC1063 detects a fault if the DP pin is left floating or is shorted to VDD. In the case of a diode
fault, the corresponding status bit will be set and the output data will be set at 400h.
SMSC EMC1063
Revision 1.37 (02-05-07)
DATA1S5HEET
SMSC [ SMSC CORPORATION ]
