Samsung Electronics Co. posted earnings that beat analysts’ estimates as stronger smartphone demand offset price declines in the memory chip business.

Operating income fell to 7.7 trillion won ($6.4 billion) in the three months ended September, according to preliminary results released Tuesday from the Suwon, South Korea-based company. That compares with the 6.97 trillion won average of analysts’ estimates compiled by Bloomberg.

Samsung, the world’s largest producer of mobile phones and smartphone displays, is benefiting from solid demand for its Note 10 and for Apple Inc.’s iPhone 11, which uses the company’s OLED displays. Still, the memory chip business has been its most profitable and uncertainties there have lingered because of the ongoing U.S.-China trade war and Japanese restrictions on the export of materials essential for chip and display production.

“Although DRAM and NAND demand is recovering and shipments in the third quarter were quite robust, there is skepticism about the sustainability of the demand upturn,” said Sanjeev Rana, technology analyst at CLSA.

Sales for the third quarter were 62 trillion won, beating the average projection compiled by Bloomberg of 61.14 trillion won. Samsung won’t provide net income or break out divisional performance until it releases final results later this month.