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Version:V1.0 —— May 2021

AHT20 Data Sheet

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should be taken to minimize the effect of heat transfer as far as possible in the design of the circuit.

For example, to maintain good ventilation of the shell, the copper coating of AHT20 and other parts of the printed

circuit board should be as smallest as possible, or leave a gap between them. (See Fig. 10)

Figure 10 The top view of AHT20 printed circuit board, the design of the milling slit is added in the figure, The heat transfer

can be reduced to a minimum.

In addition, when the measurement frequency is too high, the temperature of the sensor itself will rise and affect

the measurement accuracy. In order to ensure that its own temperature rise is low by 0.1℃, it is recommended

that the IIC frequency should be between 10K and 400KHz during measurement, and should not be too high, and

the data collection cycle should be greater than 1 second/time.

4.5 Product application scenario design

In product design, the sensor has following characteristics:

1) Sensor is in full contact with the outside air

Housing

PCB

Figure 11. Suitable windows on the enclosure provide good access to environmental measurements and allow for greater

air exchange.

2) The sensor is completely isolated from the air nside the housing

Housing

PCB

Figure 12. The sensor is isolated from the air inside the housing,

which minimizes the impact of the air inside the housing on the

sensor.

3) Small measurement dead zone around the sensor

Housing

PCB

Figure 13. Small measurement dead zone helps the sensor to

quickly and comprehensively detect environmental changes.

4) The sensor is isolated from the heat