For Consumer / IoT
LDO Linear RegulatorsPackage
Power dissipation and thermal resistance are affected not only by the size of the board but also by the number of layers, the thickness of the board, the wiring width and length, layout, etc.
When the wiring width and length, and layout pattern of whole parts are equal, the larger the board, the lower the thermal resistance.
The θja and the ψjt can be calculated by the formula below.
The actual θja and the ψjt depend on your board and mounting conditions, and may differ from the θja and the ψjt in the datasheet.
If you want to know the thermal resistance of your board with Ricoh devices, we may be able to help you by thermal simulation if you let us know the board information. Please feel free to contact us.
Definition of θja and ψjt
θja : Thermal resistance between junction temperature (Tj) and ambient temperature (Ta)
ψjt : Thermal resistance between junction temperature (Tj) and package mark surface center temperature (Tt)