We check power consumption of AD9237-40 both power scaling enable and disable .Datasheet figure 43 and 44 describle only power consumption by 10MSPS at power scaling disable and enable.Please let me knoe about power consumption when we use AD9237-40 at 6MSPS.
Question 1We think that power consumption of AD9237-40 (6MSPS) is about 90mW from figure 43.Is it correct ?
Question 2In Figure 44,slope of power consumption is varied by product name (samplng rate)
If we use AD9237-40 at 6MSPS, should we look not slope of AD9237-40 but slope of AD9237-20 at figure 44?
Could you give me advice about power consumption when we use below condtion ?
If we use slope of AD9237-40, we think that power consumption is about 50~60mW from figure 44.If we use slope of AD9237-20, we think that powe consumption is about 65~70mW from figure 44.Is is correct ?
Operated Condition Power supply: 3VMODE2 pin = 2/3 AVDD (Span factor:1, Power scaling: enabled) or MODE2 pin =AVDD (Span factor:1, Power scaling: disbled)6MSPS
If there is any question, please let me know it.
Thank you for your inquiry. Someone from David.Buchanan's team will assist you.
I apologize for the late reply. There is a problem with our message delivery system.
Because I do not have an evaluation setup ready to try on the bench, I can only give you an estimate based on information in the datasheet.
QUESTION 1: Power of AD9237-40 (6MSPS)?For analog power:Figure 43 is for analog power even though the caption says “Total Power”. I used datasheet Figure 43 for AD9237-40 and backwards extrapolated down to 6MSPS. This gives an analog power value of about 95mW at 6MSPS
For driver power:I used the IDRVDD value from the AD9237-65 and AD9237-20 to create a linear IDRVDD vs. Sample Rate relationship. I believe this will give a higher current (pessimistic) at 6MSPS than real, because the true IDRVDD vs. Sample Rate is not linear. Anyway, this yields an estimated value of IDRVDD = 2.2mA at 6MSPS, which means the power due to DRVDD = 2.2mA x 2.5V = 5.5mW at 6MSPS.
So, the estimated typical AD9237-40 total power with Power Scaling off, at 6MSPS is 95mW + 5.5mW = 100.5mW. This is with sine wave input and nominal supply voltages.
QUESTION2: Power of AD9237-40 (6MSPS) with Power Scaling. Which Power Slope to Use?For analog power:Below 20Msps, we must use the slope for AD9237-20. So, at 6Msps I agree with you that the power will be just below 70mW (let’s say 69mW). Again this is analog power.
For driver power:The driver power is not affected by Power Scaling mode, so at 6Msps the driver power will still be about 5.5mW.
So, the estimated typical AD9237-40 total power with Power Scaling on, at 6MSPS is 69mW + 5.5mW = 74.5mW. This is with sine wave input and nominal supply voltages.
Again, I'm sorry for the late reply.
Please take care,