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sinara-hw / Phaser

Quad channel 1GS/s RF generator card with dual IQ upconverter and dual 5MS/s ADC and FPGA in EEM form factor
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IC35 P1V8A supply is hot #145

Closed jbqubit closed 1 year ago

jbqubit commented 2 years ago

IC35 is power for P1V8A which supplies Si53340-B-GM (clock fanout). It is > 60 C (without fan). This seems anomalously hot. @gkasprow noted that the current is nominal.

gkasprow commented 2 years ago

@jbqubit how are you cooling the board? Do you measure temperature with PCB lying on the table or, in the rack with airflow?

jbqubit commented 2 years ago

The board is lying on a table with no rack airflow. This will be better with forced air but wanted to bring this to your attention in case there's something odd going on.

gkasprow commented 2 years ago

the clock fanout consumes ~140mA and has 3.3-1.8V =1.5V dropout. It dissipates 0.2W of power. Should not be hot at all! I'll look at it.

jbqubit commented 2 years ago
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gkasprow commented 1 year ago

I didn't find anything suspicious. I added copper area around pins to lower Rth

gkasprow commented 1 year ago

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