Synaptics (SYNA) 10-K/A 2009 FY Annual report (amended)

Exhibit 31.2

Certification of Chief Financial Officer Pursuant to
Rule 13a-14(a)/15d-14(a)

I, Kathleen A. Bayless, certify that:

1. I have reviewed this annual report on Form 10-K/A of Synaptics Incorporated; and

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.

Date: July 13, 2010

/s/ Kathleen A. Bayless  

Kathleen A. Bayless 

Chief Financial Officer