Microsoft (MSFT) Monday morning announced that its board has approved a new $40 billion stock repurchase plan, with an expiration date in September 2013. That represents about 17% of the company’s current market cap.

The company also increased its quarterly dividend to 13 cents a share, from 11 cents. The next payout will be December 11, to holders of record November 20. The new rate gives the stock a yield of about 2.1%

The company also said it completed its previous $40 billion repurchase program.

Microsoft also said its board authorized the issuance “from time to time” of up to $6 billion in debt; and it said it has established a $2 billion commercial paper program, its first-ever commercial paper issuance. Microsoft said proceeds would be for general corporate purposes, including working capital and stock repurchases.

The company said it received corporate credit ratings of AAA from S&P and Aaa from Moody’s; the commercial paper is rated A-1+ by S&P and P-1 by Moody’s, the highest rating from each agency.

Microsoft Monday morning is up $1.20, or 4.8%, to $26.36.