Dear Sir or Madam,
Could you please help with understanding the reason for the low temperature spec of the TPS71733DRVT part?
According to the data sheet this LDO is fully specified for the junction temperature of +125.
We are using 60mA and with 5V power supply will dissipate about 100mW on the part. With SON package with a ground pad the thermal resistance is 65 degree per W and thus the package will be heated by 6 degree only. It seems to be perfectly OK to take this part to +115 degree ambient and expect a proper performance.
In most on-line shops like Mouser, DigiKey, Arrow, and Avnet this part is marked as +125 degree part. However on page 18 of the specification document (Addendum-Page 5) this part is defined as specified for applications up to +85 degree. Another package without a thermal pad – WSON - has three times larger thermal resistance and will be overheated by more than 20 degree with 60mA current and by more than 66 degree at the full current of 150mA. Nevertheless you have marked WSON part as the one for +125 degree ambient, when in fact its ambient temperature limit is +60 degree ambient at full current.
It seems that the technical editor made a mistake when filling the tables in the technical sheet. It is absolutely reasonable to expect that the package with a substantially lower thermal resistance will be the one marked as the +125 degree part.
Could you please check the inconsistency in your documentation and correct it, so that we will be able to use this part in the application with the ambient temperature requirement of +115 degree at the current level of 60mA.
Thank you in advance for your assistance.
Best regards
Victor Zhitomirsky (Dr.)
