Hitachi, Ltd. and a semiconductor unit of Germany's Siemens AG announced Thursday they have agreed to jointly develop and manufacture an advanced compact memory chip suitable for portable digital products.

Hitachi and Infineon Technologies AG said they will cooperate in joint product specifications and production of the MultiMedia Card and promote it as an industry standard.

The next-generation memory chip inexpensively combines a large-capacity flash memory with a controller to make the world's smallest flash memory card, the officials said.

"Hitachi is strong in high-density flash memory technology, while Infineon has interface expertise in MultiMediaCard. We can combine the technological strength of the two (through the partnership)," said Tadashi Ishibashi, president of Hitachi's semiconductor and integrated circuits division.

Although the flash card is suitable for portable multimedia products such as digital cameras and portable audio players, Hitachi considers cellular phones the market with most potential, the officials said.

The two firms have already developed the 16-megabyte MultiMediaCard and Hitachi will start sample shipping the product next month. They will jointly develop and introduce a 32-megabyte MultiMediaCard by the end of this year, the officials said.

The firms plan to introduce a 64-megabyte flash card next year and launch 128-megabyte versions in 2001, the officials said.

Hitachi plans to start manufacturing about 50,000 cards a month in the current fiscal year and hopes to increase production to 1 million a month in the next fiscal year, the officials said.