Spot prices for flash memory chips used in smartphones and tablets could jump after the Japanese earthquake, although it would likely have only a limited impact on global supplies, an analyst said.

Toshiba, the world's second biggest supplier of NAND flash memory after Samsung, closed its factories after the devastating earthquake and tsunami on Friday.

Its plant in Iwate, closest to the quake, makes microcontrollers, although the company did not have any information about possible damage, a spokesman said.

Its main NAND facility is further down the coast in Yokkaichi, near Tokyo, he said, and he did not think it had been badly affected.

Gartner analyst Andrew Norwood said the earthquake and tsunami could hit spot prices but it should not have a long-term impact on the market.

"Particularly the spot market tends to react very wildly to any kind of uncertainty or doubt.

"In the past both DRAM and NAND (memory chip prices) have jumped after such an event, but given that it happened late on Friday, and most of the spot market is in Asia, they are going to have 48 hours to digest what is happening and hopefully come to more reasonable conclusions rather than over-reacting."

Toshiba supplies more than a third of the NAND memory chips used worldwide in devices like Apple's iPad.

"Certainly there will be some impact on transportation and logistics, but as to the damage on the factory level, we do not know," said a Toshiba spokesman based in Dusseldorf, Germany.

"We will probably get that information tomorrow or on Monday morning."

Sony shut six factories, two in Fukushima and four in Miyagi, including a plant making laser diodes used in DVD, Blu-ray and CD ROM players and Playstations, and Panasonic halted production.

Analyst Mark Harding at Maxim Group in New York said the quake would clearly have a negative impact on Sony, although it was too early to say what the extent would be.

"From the onset it's going to be marginally negative, and the longer it takes the worse it's going to be," he said.

However, the impact would be slightly mitigated by the facts that Sony had moved some manufacturing outside Japan and that the disruption had not come at a peak time.

"At this time it's typically the seasonally slower period in terms of consumer consumption," he said.

(Reporting by Paul Sandle)