Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

The measurement of PSRR for a 10-bit SAR ADC

Status
Not open for further replies.

howardtang85

Newbie level 6
Joined
Nov 3, 2010
Messages
13
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,367
Hi all,

I have designed a 10-bit SAR ADC. Now I need to measure the PSRR performance of the ADC.

I read some articles. It says I will need to inject a 100mV sine wave to the power supply and ground the input. Capture the output code and process it with FFT. I have done so and get a spur of -72dB at 1kHz (the supply noise is 1kHz). May I know how to calculate the PSRR in this case?


Thanks!
 

crutschow

Advanced Member level 5
Joined
Feb 22, 2012
Messages
3,790
Helped
903
Reputation
1,804
Reaction score
888
Trophy points
1,393
Location
L.A. USA Zulu -8
Activity points
21,359
The PSRR is referenced to the full-scale input voltage of the ADC. What is the -72dB referenced to?
 

goodboy_pl

Full Member level 5
Joined
Mar 12, 2002
Messages
253
Helped
16
Reputation
32
Reaction score
15
Trophy points
1,298
Activity points
3,119
howardtang85,
you must also inject the 100mv signal only to the ADC input and measure its power using fft method, then subtract result of the first measurement from second.

BEST
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top