It will get the first tranche on November 25, with the rest paid out on December 8.
Amphion has stakes in seven partner companies aiming to support and develop their value.
Its partner companies collectively own or control more than 200 separately identified pieces of IP.
Amphion set up the initial financing last year in the form of a US$2mln share-backed loan from an institutional lender, with the potential to increase it to US$10mln.
Under the terms of the extra draw-down, the simulated warrants over Kromek Group (LON:KMK), one of its partner companies, will be cancelled, the interest rate on the facility will be reduced from 12% to 10%, and no additional Amphion warrants will be granted.
The remaining terms of the draw-down remain substantially the same.
Broker Northland Capital said: “Amphion has effectively drawn down an additional US$3mln on improved terms to its previous facility.
“We view this as a clear step in the right direction—the group continues to strengthen its balance sheet.”
The proceeds will be used to repay the existing amount due under the facility and for working capital for Amphion and its partner companies.