Dialog Semiconductor, which supplies power management chips for Apple's iPhone, is in talks to acquire Synaptics, the maker of touch-screen and display technology used in mobile devices, according to a person familiar with the matter. Bloomberg previously reported the talks.

Dialog, which has a market capitalization of about $1.1 billion, is smaller than Synaptics, whose market capitalization is about $1.5 billion. No deal is assured, said the people, who asked not to be named because discussions are private.

Talks have been ongoing for months, the sources said. Dialog's initial offer in March for Synaptics was about $59 per share and all cash, according to a person familiar with the matter. Synaptics rejected that offer, so if a deal gets done, it will probably be at a higher price than that, the person said.

Dialog's share price has plummeted, down more than 60 percent in the past 52 weeks. Dialog shares fell 17 percent last week, to a four-year low, after Apple said it would cut orders for its power-management chips by around 30 percent this year. Dialog told investors that Apple planned to source its main power-management chips (PMICs) for one of its three new iPhone models from two suppliers instead of just from Dialog.

Both Dialog and Synaptics have dealt with botched acquisitions in recent years. Synaptics couldn't close on a sale to a China-based buyer in 2016, and Dialog failed to acquire Atmel the same year when Microchip made a superior offer.

A deal, if completed, will test regulators' appetite to approve cross-border semiconductor transactions. Companies have been reluctant to move forward with global acquisitions since the U.S. government blocked Broadcom's attempt at buying Qualcomm earlier this year.

A spokesman for Synaptics declined to comment. A spokeswoman for Dialog couldn't immediately be reached for comment.