EMC1422 SMSC Corporation, EMC1422 Datasheet - Page 21

• Manufacturer Part Number: EMC1422
• Description: 1C Temperature Sensor
• Manufacturer: SMSC Corporation

1°C Temperature Sensor with Hardware Thermal Shutdown
Datasheet
SMSC EMC1422
5.10
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0
Temperature Monitors
0
Δ
In general, thermal diode temperature measurements are based on the change in forward bias voltage
of a diode when operated at two different currents. This ΔV
as shown in the following equation:
Figure 5.6
the remote temperature diode, DN, is internally biased with a forward diode voltage referenced to
ground.
V
BE
=
shows a block diagram of the temperature measurement circuit. The negative terminal for
2
η
kT
q
Figure 5.5 Temperature Filter Impulse Response
ln
Filter Impulse Response
⎛
⎜ ⎜
⎝
4
I
I
HIGH
LOW
Disabled
⎞
⎟ ⎟
⎠
DATASHEET
6
Samples
21
Level1
8
where:
k = Boltzmann’s constant
T = absolute temperature in Kelvin
q = electron charge
η
= diode ideality factor
BE
is proportional to absolute temperature
10
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Revision 1.16 (03-15-07)
Level2
14
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