[SOLVED] Synchronous Buck Converter Using IR2184

[CrocLeather]

I have made a synchronous buck converter using ir2184 which i intend to use for MPPT using a P&O algorithm. The MOSFETs i am using are IRFZ44n which i connected with a 10 ohm gate resistor. My VCC bias is a 1W 16V zener diode and my bias resistor is 470 ohms. My bootstrap circuit is composed of a 220nF cap and 1n4148 diode. My VCC capacitor is 2.2uF. I am using an arduino nano and TimerOne library which enables me to send a signal of 50kHz to the IN of IR2184. I have not yet tested it on solar panel and tried it using a power supply and electronic load. My problem is that as I try to increase the power of the system by decreasing the load resistance which in turn should increase the load current, the output voltage becomes very far from the ideal output voltage which is calculated using the duty cycle and input voltage. Is this normal or are there issues with this? Thank you.

 

[cupoftea]

Is your inductor saturating?
Is youur layout really good...no swiching node over sensitive signals...no power switching current flowing through ground lengths.?

 

[KlausST]

Hi,

For good assistance we need:
* Schematic
* exact part names
* PCB layout

Klaus

 

[CrocLeather]

Hello. I would like to ask if I still need to connect the GND pin of the arduino to the GND of the buck converter? The power source of the arduino will come from a power bank. The pin 9 of the arduino will be connected to the IN pin of the IR2184.

 

[FvM]

I would like to ask if I still need to connect the GND pin of the arduino to the GND of the buck converter?

Yes. Drivers like IR2184 require a common ground between pwm source and output stage. Even drivers with separate logic ground (e.g. IR2110) tolerate only a few volts offset between COM and VSS pin.