LTC2870IFE Thermal Data

Hi RamaManikandan,

TJMAX or the Max Case temperature = 150°C

The junction-to-case thermal resistance of the LTC2870IFE is 5-10C/W. I believe it's been answered before. LTC2870IFE junction-to-case resistance - Q&A - Interface and Isolation - EngineerZone (analog.com) I don't think we have the R_θJB metric for this 38 -lead TSSOP package. I will confirm this with the assembly/packaging engineer and get back to you.

Regards,

Naveen

Junction to board thermal resistance is approx 34-39°C/W.

Regards,

Naveen

Hi  Naveen Afzal,
I was confused because you have mentioned R_θJB as value for 38-Lead Plastic TSSOP in your first comment.

Please acknowledge once that you have mentioned Tc(max) and R_θJB you have mentioned is for  LTC2870IFE#PBF 28-Lead Plastic TSSOP.

And Kindly also attach the value of Power dissipation value of LTC2870IFE#PBF. 

Hi,

Junction to board thermal resistance for the  28-Lead TSSOP is 34-39°C/W and TJ max is 150°C. I rechecked. The power dissipation will depend on the operation conditions too. It is approx 632 mW (worst case).

Regards,

Naveen

Thanks for the quick reply Naveen Afzal
Whether PDML file is available for this component. If yes please attach the file.

Hi Naveen Afzal
Please explain at what condition this high power dissipation of 632 mW will occur and also kindly provide the Power consumption for that same condition.

Please explain at what condition this high power dissipation of 632 mW will occur and also kindly provide the Power consumption for that same condition.

Hi RamaManikandan,

We don't have that file available for this part.

Regards,

Naveen

Hi RamaManikandan,

Max power consumption is 632 mW (worst case at -40degC and max rate 20mbps). That figure can be estimated from the datasheet. 

Max power dissipation is around 253 mW as there will be a power dissipated across the termination load. You can see this from the datasheet too. (3.7V & 54 ohm load) when it is in RS485 mode (worst case) . A logic high on the 485/232 pin enables the RS485 mode.

Regards,

Naveen

Can you please provide the Maximum Power Dissipation value for LTC2870IFE at 3.3V supply.

In the Previous comments it seems like you have calculated with help of Load resistance seen by the driver. But how can we consider only this load resistance of driver while calculating the entire Power dissipation of the device? Is this methodology of calculating maximum power dissipation of entire IC is correct? Kindly explain