Tool/software:
Dears:
I found OPA210 just show the GBW is 18MHz and test condition is empty, Please help provide test condition such as OPA189 showing in DS.
BTW , I noticed that some device provide GBW and some provide BW, Could I have your support to know the difference ? Thanks.
Hi Haiwen,
I found OPA210 just show the GBW is 18MHz and test condition is empty, Please help provide test condition such as OPA189 showing in DS.
Here is the OPA210's GBW and test conditions. You can simulate it via simulator such as Tina-TI or PSpice-For_TI or other tools.
For OPA189, the GBW and test conditions can be found in the image below.
BTW , I noticed that some device provide GBW and some provide BW, Could I have your support to know the difference ?
In OPA189, the internal op amp pole roll off is slightly complicated, because it is a chopper amplifier. OPA210 is easier to see the roll off trend, which is a standard -20dB/decade.
GBW typically refers to Gain*Bandwidth Product (assume linear relationship in GBWP), where the BW refers to an op amp's dominated pole at -3dB point. UGB or UGBW refers to the frequency at Unity Gain Bandwidth at 0dB in a Bode plot.
BW has to go with the context in a DS. It could refer to pole at -3dB point in GBW/GBWP. It could mean GBW/GBWP in an open loop; or it could mean the frequency at closed-loop; it could mean BW at G=1 (UGBW/UGB) or it could mean an op amp BW at particular gain settings. it depends on a context. If it is in a table format, it typically refers to bandwidth at -3dB point of a closed-loop circuit.
If you have other questions, please let me know.
Best,
Raymond
Raymond:
About OPA210, customer use Vpp= 50mV input, Gain=1, -3db frequency is 13.6MHz, much lower than 18MHz, Could you please help check 18MHZ GBW test condition ? use Vpp =50mV or other amplitude ?
Hi Haiwen,
About OPA210, customer use Vpp= 50mV input, Gain=1, -3db frequency is 13.6MHz, much lower than 18MHz,
Since OPA210 has larger UGBW (unity gain bandwidth), the AC response will exceed 13.6MHz.
Could you please help check 18MHZ GBW test condition ?
If the customer has to configure -3dB at 13.6MHz, they have to use LPF or active filter to limit the op amp's BW. Example may be like below.
This RC filter at output should also cap the higher frequency noise for the OPA210 (above 13.6MHz).
If the customer wants to have sharper cutoff/roll-off frequency, it may have to use active LPF filter, such as Sallen-key or MFB, but noise will be higher.
If you have other questions, please let me know.
Best,
Raymond
