Thermal resistance from junction to ambient, Thermal resistance from junction to board – Rainbow Electronics AT84AD001B User Manual

Page 57

Advertising
background image

57

AT84AD001B

2153C–BDC–04/04

Thermal Resistance from
Junction to Ambient

The thermal resistance from the junction to ambient is 25.2

° C/W typical.

Note:

In order to keep the ambient temperature of the die within the specified limits of the
device grade (that is T

A

max = 70°C in commercial grade and 85°C in industrial grade)

and the die junction temperature below the maximum allowed junction temperature of
105°C, it is necessary to operate the dual ADC in air flow conditions (1m/s recom-
mended).


In still air conditions, the junction temperature is indeed greater than the maximum
allowed T

J

.

- T

J

= 25.2°C/W x 1.4W + T

A

= 35.28 + 70 = 105.28°C for commercial grade devices

- T

J

= 25.2°C/W x 1.4W + T

A

= 35.28 + 85 = 125.28°C for industrial grade devices

Thermal Resistance from
Junction to Board

The thermal resistance from the junction to the board is 13

° C/W typical.

Advertising