Dec 10 (Reuters) - Broadcom Inc on Thursday appointed its principal accounting officer, Kirsten Spears, as chief financial officer and forecast first-quarter revenue above estimates as key client Apple Inc doubles down on 5G devices, driving demand for its chips.

Spears replaces Tom Krause, who has been named president of Infrastructure Software Group, which oversees the chipmaker's six software divisions. Chief Sales Officer Charlie Kawwas was also named chief operating officer.

Shares of Broadcom, however, fell 2% in extended trading after the company warned of soft demand from enterprise clients.

Supply disruptions due to the COVID-19 pandemic continue to persist, Chief Executive Officer Hock Tan said.

Broadcom is seeing deceleration in orders for its wireless business, which was offset by strong demand for other products, Tan added.

The global roll out of 5G technology is expected to boost sales of higher-priced chips used in next-generation smartphones, helping semiconductor firms such as Broadcom.

The company expects first-quarter revenue to be about $6.6 billion. Analysts on average were expecting $6.52 billion, according to IBES data from Refinitiv.

For the fourth quarter, revenue rose 12% to $6.47 billion, above Wall Street estimates of $6.43 billion.

Excluding items, the company reported a profit of $6.35 per share, topping analysts' expectations of $6.25.

The company's shares have gained nearly 30% this year, but lag the broader Philadelphia SE Semiconductor Index, which is up about 48%. (Reporting by Munsif Vengattil in Bengaluru and Stephen Nellis in San Francisco; Editing by Anil D'Silva and Shinjini Ganguli)