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OPA355-Q1: Output is not come when I give 100MHz Sine wave input

Part Number: OPA355-Q1
Other Parts Discussed in Thread: TINA-TI, OPA695


We have used OPA355-Q1 Operational Amplifier in one of our project. Schematic is attached for your reference

When I give 100MHz Sine wave input with amplitude of 2Vpp, Operational Amplifier OPA355-Q1 is not giving output (0V observed). Will this part support for 100MHz frequency application ?.

if Not, please suggest a suitable part for 100MHz application.Sheet2.pdf

  • Hi Mani,

    why not running a TINA-TI simulation?



  • Hey Mani, thanks for the schematic, couple of comments, 

    1. don't use such high R's on the V+ reference, and add a noise filtering cap - maybe go with 10kohm values and a 1uF cap. 

    2. You cannot run directly out to an SMA for a matched impedance line, need to isolate the line capacitance with 50ohm R - if you are terminating in 50ohms then you need to get more swing, like 4Vpp with 1kohm input R. 

    3. You will need some serious slew rate to pass that signal on - a 100Mhz 4Vpp swing requires 1256V/usec - and you would need some margin to that. Not many low gain stable parts will do that with 4Vpp on single 5V supply. you may need to go current feedback with something more like -2.5V and +7.5V supplies - OPA695 is one option, but then scale the R's to what it needs for compensation, more like 499ohm for each one if gain of 1 is indeed requried.