Hawaslsh
Full Member level 3
- Joined
- Mar 13, 2015
- Messages
- 164
- Helped
- 5
- Reputation
- 10
- Reaction score
- 7
- Trophy points
- 1,298
- Location
- Washington DC, USA
- Activity points
- 3,422
Hello,
I have run into an odd problem and I don't know exactly why it's happening. I am using an Arduino UNO to program a ADF4153A which in turn is controlling a VCO HMC739. All are powered by the same bench top power supply. The ADF4153A has its own 3.3V voltage regulator. Above is a diagram of the PLL, the loop filter and register settings were created in ADIsimPLL and locks very well. However when its connected to the Aruino UNO board it produces a harmonic around the center frequency.
I suspect it's the arduino board causing this; after power up, and writing registers in the ADF4153A, I can un-power the arduino and the harmonics go away.
A fun bonus, when i have the USB cable attached to the Arduino (open ended or plunged in) the harmonics become quite pronounced. The cable is quite long, perhaps 1 meter.
Any idea why this is happening? A suggestion on how to suppress it? This will be an issue down the line if/when all of this gets integrated into a single unit.
Let me know if any you want any more details, and thanks in advance!
Sami
I have run into an odd problem and I don't know exactly why it's happening. I am using an Arduino UNO to program a ADF4153A which in turn is controlling a VCO HMC739. All are powered by the same bench top power supply. The ADF4153A has its own 3.3V voltage regulator. Above is a diagram of the PLL, the loop filter and register settings were created in ADIsimPLL and locks very well. However when its connected to the Aruino UNO board it produces a harmonic around the center frequency.
I suspect it's the arduino board causing this; after power up, and writing registers in the ADF4153A, I can un-power the arduino and the harmonics go away.
A fun bonus, when i have the USB cable attached to the Arduino (open ended or plunged in) the harmonics become quite pronounced. The cable is quite long, perhaps 1 meter.
Any idea why this is happening? A suggestion on how to suppress it? This will be an issue down the line if/when all of this gets integrated into a single unit.
Let me know if any you want any more details, and thanks in advance!
Sami
Last edited: