Hi~
I got an issue report about OPA4172 Iq current from our customer.
One of our customer is using OPA4172 as voltage follower and application is test board for display controller.
Structure is as below
DAC(AD5379) - OPA4172(10ea) - Killimanjaro chip - FPGA chip
There's no F/W inside DAC and output stage of OPA4172 is open state.(open to K-chip)
When power(+10V, -5V) connected to opa4172, Iq current thru -5V was about 20mA per ch.
So I checked schematic and found two capacitors(0.47uF, 0.1uF) in output port.
After removing two caps, Iq current became 4.5mA~2.8mA.
When we changed OPA4172 to OPA4192, above phenomenon didn't occurred.(Iq=3.5mA)
Would you please explain what characteristic makes these phenomenons(high Iq and Iq variance) between OPA4172 and OPA4192.
Thanks in advance.
