Heartland Payment Systems Inc. said Wednesday that it is working with Voltage Security Inc. of Palo Alto, Calif., to develop an encryption system for card payments.

Heartland, which already uses Voltage software to protect data on its corporate network, has championed end-to-end encryption of payment data ever since the Princeton, N.J., processor disclosed a data breach in January.

"Heartland is developing a complete end-to-end encryption solution designed to protect cardholder data at all stages of a transaction — from card swipe through delivery to the card brands," Bob Carr, its chairman and chief executive, said in a press release Wednesday.

Heartland expects the E3 encryption system to be tested next quarter.