Apple Inc.'s slowing sales are rippling through a supplier network that has long benefited from the company's ability to churn out iPhones and iPads.

Cirrus Logic Inc., a maker of audio chips that gets 91 percent of its sales from Apple, this week reported an inventory glut that suggested slowing iPhone sales, and forecast fiscal first-quarter revenue below analysts' estimates. Hon Hai Precision Industry Co., Apple's top supplier, this month posted its biggest revenue decline in at least 13 years, indicating slower sales of smartphones, tablets and computers.

Apple's breakneck growth to $156.5 billion in revenue last year, from $24.6 billion in 2007 when the iPhone debuted, supports an ecosystem of at least 247 suppliers across the globe. They relied on Apple to deliver $30.1 billion in orders in the latest reported quarter, according to supply-chain data compiled by Bloomberg. As a result, many are now vulnerable after building up inventory in anticipation of continued growth, according to Michael Hasler, a lecturer at the University of Texas in Austin.