I'm building a battery charger circuit with BQ24278. The battery draws 500mA minimum and 2.5A maximum current; therefore, I must prevent IC from overheating. I printed the board onto single sided copper plate with ironing method and unfortunately there is no opportunity to drill the copper plate since I don't have a proper drill equipment. So, considering my restriction, is there a practical way to cool down the chip? I already have DC fan and heatsink for TO-92 package; however, since I have burned out 2 ICs already, I would like to apply a solution by getting ideas of other people.
I connected AGND and PGND under the bq24278, and put as much copper as I can. I attach the datasheet and the circuit diagram.