Online through http://RenesasSamples.com. Use parametric search or enter a part number
Authorized Distributor or Sales Representative
Contact an authorized Renesas distributor or the sales representative in your area. Find the one nearest you by visiting https://www.renesas.com/en-us/support/contact.html.
Visit the product page for the part number of interest and select the Ordering tab which displays a table which includes a column for ordering samples.