ADN2530 Analog Devices, Inc., ADN2530 Datasheet - Page 14

• Manufacturer Part Number: ADN2530
• Description: 11.3 Gbps, Active Back-termination, Differential Vcsel Driver
• Manufacturer: Analog Devices, Inc.

ADN2530
A compact optical module is a complex thermal environment,
and calculations of device junction temperature using the
package θ
yield accurate results. The following equation, derived from the
model in Figure 38, can be used to estimate the IC junction
temperature:
where:
T
T
Celsius.
T
P is the ADN2530 power dissipation in watts.
θ
θ
exposed pad.
T
J-TOP
J-PAD
TOP
PAD
J
J
is the IC junction temperature in degrees Celsius.
=
is the temperature at package exposed paddle in degrees
is the temperature at top of package in degrees Celsius.
is the thermal resistance from IC junction to package top.
is the thermal resistance from IC junction to package
P
×
(
JA
θ
J
(junction-to-ambient thermal resistance) do not
−
PAD
×
θ
J
−
TOP
θ
)
J
−
+
PAD
T
TOP
+
θ
×
J
θ
−
TOP
J
−
PAD
+
T
PAD
×
θ
J
−
TOP
Rev. A | Page 14 of 20
T
at points inside the module, as shown in Figure 37. The thermo-
couples should be positioned to obtain an accurate measurement of
the package top and paddle temperatures. θ
given in Table 2.
TOP
and T
Figure 38. Electrical Model for Thermal Calculations
PAD
can be determined by measuring the temperature
P
T
TOP
T
θ
T
θ
T
J
J-PAD
PAD
J-TOP
PAD
T
TOP
J-TOP
and θ
J-PAD
are