Exhibit 32.2

                                  CERTIFICATION

Pursuant to the requirement set forth in Rule 13a-14(b) of the Securities
Exchange Act of 1934, as amended, (the "Exchange Act") and Section 1350 of
Chapter 63 of Title 18 of the United States Code (18 U.S.C. Section 1350), Greg
Hildebrand, Chief Financial Officer of Volterra Semiconductor Corporation (the
"Company") hereby certifies that, to the best of his knowledge:

1. The Company's Quarterly Report on Form 10-Q for the period ended September
30, 2004, to which this Certification is attached as Exhibit 32.2 (the "Periodic
Report"), fully complies with the requirements of Section 13(a) or Section 15(d)
of the Exchange Act; and

2. The information contained in the Periodic Report fairly presents, in all
material respects, the financial condition of the Company at the end of the
period covered by the Periodic Report and results of operations of the Company
for the period covered by the Periodic Report.

IN WITNESS WHEREOF, the undersigned has set his hand hereto as of the 28th day
of October, 2004.

                                              /s/ Greg Hildebrand
                                              -------------------------------
                                              Greg Hildebrand
                                              Chief Financial Officer

This certification accompanies the Form 10-Q to which it relates, is not deemed
filed with the Securities and Exchange Commission and is not to be incorporated
by reference into any filing of Volterra Semiconductor Corporation under the
Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as
amended (whether made before or after the date of the Form 10-Q), irrespective
of any general incorporation language contained in such filing.