ZMOD4450 Datasheet

© 2021 Renesas Electronics Corporation

10

June 30, 2021

Table 6.

Default Parameters for Control Signal based on Air Quality Changes

Parameter

Conditions

Typical Value

Unit

Learning Time Environment

Typical value valid for sample rate of 2 seconds

60

min

Sensor Module Response Time

Sample rate dependent, typically 1 to 3 samples

10

s

Threshold Trigger

Change of concentration; recommended difference: 30%

1.3

–

Stop Delay

Stop delay for external device; defines minimum activation time

2

min

When using the ZMOD4450 Evaluation Kit, the AD5 pin (GPIO) on connector K3 on the HiCom Communication Board is the trigger control

signal output that is set to HIGH/LOW. For more details, refer to the ZMOD4450 Evaluation Kit User Manual.

7.2 Environmental Temperature and Humidity

The sensor module is tested, qualified, and functional in the operation range of 0°C to +25°C. Figure 3 shows the module’s response during

operation to variations in relative humidity with and without ethylene stimulation.

Figure 3. Humidity Influence at 4°C for Ethylene Stimulation

7.3 Accuracy and Conditioning

All Renesas gas sensor modules come with electrical and chemical factory calibration with data stored in the module’s nonvolatile memory

(NVM). Using the software provided by Renesas and the calibration coefficients in the NVM will lead to stable measurements. The ZMOD4450

will respond to typical refrigeration gases immediate upon start-up; however, a conditioning period of 48 hours in a refrigeration environment is

recommended to improve stability and get maximum performance, as the module algorithm is able to learn about the refrigeration environment

over time.

Users who require an absolute measurement with the maximum achievable accuracy are advised to re-calibrate the sensor module with a

known organic compound. This enables an absolute accuracy of ±15% (see Table 7). For some environments, an interference response to

siloxanes is of concern; however, the ZMOD4450 gas sensor module is proven to be resistant against siloxanes. A maximum potential life-time

exposure has been simulated in all ZMOD4450 operation modes by applying the chemicals D4 (octamethylcyclotetrasiloxane) and D5

(decamethylcyclopentasiloxane) in high concentration for several hundred hours.

1E+5

1E+6

1E+7

50

60

70

80

90

100

Relative Humidity [%]

Clean Air

Ethylene 0.2 ppm