Doc ID 15772 Rev 2

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AN2991

Conclusion

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4

Conclusion

Reliable electronic thermostats can now be used instead of older bimetallic solutions. This

allows large efficiency gains to be achieved, thanks to the PTC removal and to a tighter

temperature management.

These improvements can also allow downsizing of the compressor and the evaporator.

Switching to MCU based controls will allow higher flexibility and adaptability, and will help

enhance the differentiation of appliances. Automatic routines (like defrost cycle) can be

implemented and the end-user interface can be improved (temperature information, open

door warning, temperature alarm, smooth light-up of the internal bulb by electronic dimming,

etc.).

In terms of cost, electronics can now be competitive with electromechanical devices. A

complete thermostat board, plus the sensor, can reach a cost similar to electromechanical

thermostats. Furthermore, some features, such as extended life time or spark-free

operation, come for free with electronics.

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Revision history

Table 2. Document revision history

Date

Revision

Changes

29-May-2008

1

First issue under new code. Previously published as AN1354.

05-Sep-2013

2

Updated Figure 4 and Figure 7. Replaced ACST6 with ACST610.