Silver Lake is set to plow more than $1 billion -- its biggest check yet -- to back Broadcom Ltd.’s proposed takeover of Qualcomm Inc., according to a person with knowledge of the matter. The check would be part of $5 billion in convertible debt financing that the private equity firm has pledged to the giant chipmaker deal, which is valued at $130 billion including net debt. It’s Silver Lake’s largest-ever commitment to a transaction, the person said, asking not to be identified because the details are private.