In case you didn't know about this plan here is the idea in a nutshell. The President authorizes the US Mint to create a $1Trillion platinum coin and then deposit it in the treasury. Pooof...the debt ceiling crisis vanishes.
The Republicans are so afraid of having the rug pulled out from under their blackmail attempt that they are trying to pass a law that prohibits the minting of said coin.
The coin doesn't actually have to have a trillion dollars worth of platinum. Just the face value has to be $1Trillion. There are laws that regulate the printing of paper money, and gold and silver coins. But a loophole in the law excludes platinum. The law was written that way to allow companies the right to mint platinum commemorative coins without violating our counterfeiting laws.
The theory is that a $1 trillion platinum coin is minted and placed on deposit with the treasury. The countries money supply doesn't change, so hence no inflation. But, when the accounting is done our country is $1 trillion short of the debt ceiling. Therefore there would be no need to ask congress to raise the debt limit.
The idea is that the Republicans would find the minting of this coin more distasteful than raising the debt ceiling.