20A 5V single chip DC-DC converter IC with 5mohm MOSFET switch

In this paper, we demonstrate 20 A operation and high switching frequency 980 KHz of single chip DC/DC converter. The fabricated chip consists of the digitally control block, the low on-resistance MOSFET switches and the drivers. The chip adopted low impedance metal bump technology. The on resistance of Nch MOSFET is 4.3m (@drain current=10 A, gate voltage=5 V) comparable to the discrete device. The fabricated chip achieves maximum output current 24 A and max efficiency 91.2% for the input voltage, the output voltage and switching frequency of 5 V, 1.083 V and 980 KHz, respectively. The efficiency without power loss by the parasitic resistance on PCB and output filter is 81.9% at the output current 20 A.