Post Go back to editing

How to decide load resistor for best performance at DAC voltage output?

Category: Datasheet/Specs
Product Number: ADV7391


I tried to design RS170(voltage output level 1V) application board with ADV7391 using full-drive (Rset: 510ohm, RL: 37.5 ohm).

In ADV7391 data sheet rev.j, the recommended load resistor consists of 37.5 ohm to expect 34.7mA full-scale current(1.3V) at p.72, p.69, and p.7.

However, fig. 93 shows that the recommended RL is 75 ohm. At this point, I'm curious about which value is best for the performance.

Or, the additional resistor is required to get 37.5ohm load resistor as mentioned in

At summary, my questions are

1. If only 75ohm load resistor satisfies the best performance @ fig.93, what is the relation between Rset and RL with Vaa to calculate DAC voltage output level?

2. In ADV7179 datasheet, they describe load resistors 75ohm for the best performance. If the fact also can adapt to the ADV7391, is the based theory doubly terminated 75ohm load as described in AN205 application note and CN-0264(rev.0)?

3. If only load resistor 75 ohm is adopted without monitor impedance , which level of the output current is right? (34.7mA / 2 or 34.7mA x 2)

Thank you for your time.

Best regards,


adv7191 datasheet add
[edited by: mcpark09 at 4:14 AM (GMT -5) on 29 Dec 2023]