The dollar held steady against the yen and hovered near a half-year low against the euro, with many currency dealers hesitant to take positions ahead of the Fed minutes.
Speculation that the US central bank is poised to begin tapering its $85 billion a month in asset purchases as early as September is generally positive for the dollar, as it tends to lift US Treasury yields.
But it can also pressure equities and increases the appeal of perceived safe-haven currencies, such as the yen and Swiss franc.
At its policy meeting in early August, the European Central Bank (ECB) had left interest rates at a record low of 0.5 percent and affirmed that they will remain there for some while to come and could yet fall further.
The franc rose to record levels through the global recession before pulling back after the Swiss National Bank imposed a 1.20 per euro cap. It remains at historically high levels despite recent apparent improvements in global economic conditions.
The SNB has vowed to keep the cap in place for as long as needed.
The franc was unchanged against the dollar compared to the New York close at 0635 GMT.
The franc was also unchanged against the euro.