Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications
Datasheet
5.2
5.3
Conversion Rates
The EMC1182 may be configured for different conversion rates based on the system requirements.
The conversion rate is configured as described in Section 6.5. The default conversion rate is 4
conversions per second. Other available conversion rates are shown in Table 6.6, "Conversion Rate".
Dynamic Averaging
Dynamic averaging causes the EMC1182 to measure the external diode channels for an extended time
based on the selected conversion rate. This functionality can be disabled for increased power savings
at the lower conversion rates (see Section 6.4, "Configuration Register 03h / 09h"). When dynamic
averaging is enabled, the device will automatically adjust the sampling and measurement time for the
external diode channels. This allows the device to average 2x or 16x longer than the normal 11 bit
operation (nominally 21ms per channel) while still maintaining the selected conversion rate. The
benefits of dynamic averaging are improved noise rejection due to the longer integration time as well
as less random variation of the temperature measurement.
When enabled, the dynamic averaging applies when a one-shot command is issued. The device will
perform the desired averaging during the one-shot operation according to the selected conversion rate.
When enabled, the dynamic averaging will affect the average supply current based on the chosen
conversion rate as shown in Table 5.1.
Table 5.1 Supply Current vs. Conversion Rate for EMC1182
AVERAGE SUPPLY CURRENT
(TYPICAL)
AVERAGING FACTOR (BASED ON
11-BIT OPERATION)
ENABLED
(DEFAULT)
ENABLED
(DEFAULT)
CONVERSION RATE
DISABLED
DISABLED
1 / 16 sec
1 / 8 sec
1 / 4 sec
1 / 2 sec
1 / sec
210uA
265uA
330uA
395uA
460uA
890uA
1010uA
1120uA
1200uA
1400uA
200uA
200uA
200uA
200uA
215uA
325uA
630uA
775uA
1050uA
1100uA
16x
16x
16x
16x
16x
8x
1x
1x
1x
1x
1x
4 / sec (default)
8 / sec
1x
4x
1x
16 / sec
2x
1x
32 / sec
1x
1x
64 / sec
0.5x
0.5x
5.4
THERM Output
The THERM output is asserted independently of the ALERT output and cannot be masked. Whenever
any of the measured temperatures exceed the user programmed Therm Limit values for the
programmed number of consecutive measurements, the THERM output is asserted. Once it has been
asserted, it will remain asserted until all measured temperatures drop below the Therm Limit minus
the Therm Hysteresis (also programmable).
SMSC EMC1182
19
Revision 1.0 (07-11-13)
DATASHEET
SMSC [ SMSC CORPORATION ]
