Data Sheet

ADA4870

APPLICATIONS INFORMATION

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Rev. B | 21 of 24

All testing was done in a still-air environment. Forced air convection

in any of the test cases effectively lowers θJA and moves the

corresponding curve toward the upper right, expanding the SOA.

For more information on the ADA4870 evaluation board, see the

ADA4870 User Guide.

In Figure 74, the horizontal line at 1 A is the output current drive

of the ADA4870. The curved section maintains a fixed power

dissipation that results in a junction temperature (TJ) of 140°C or

less. Note that the x-axis is the output stage VCE (VCC − VOUT

or VOUT – VEE) developed across the relevant output transistor of

Figure 72 and ends at a maximum VCE of 20 V.

Figure 74. Safe Operating Area for Evaluation Board from Figure 75 at 25°C

and 85°C Ambient Temperature With and Without Heat Sink, No Air Flow

Figure 75. Details of the ADA4870 LFCSP Evaluation Board