Image source: InvenSense.

Shares of InvenSense (NYSE:INVN) have fallen around 30% so far in 2015, with the bulk of those declines occurring after the motion chip specialist's fiscal first-quarter 2015 report almost three months ago. So in anticipation of InvenSense's fiscal second-quarter results later this week, you might be able to hear a pin drop in the moments leading up to its release.

The great quarter that wasn't
The thing is, in July InvenSense CEO Behrooz Abdi rightly called fiscal Q1 a "solid quarter," as both revenue (up 59% year over year) and earnings (up 10.5%) came in ahead of Wall Street's expectations. To be sure, the company enjoyed what Abdi described as a "strong market position in our core motion products across the majority of OEMs," while its optical image stabilization (OIS) solutions continued to grow in popularity with major OEMs across the globe.

However, InvenSense also followed with much more conservative guidance for fiscal Q2. Specifically, quarterly revenue this time should be $106 million to $114 million (up 22% at the midpoint), which should translate to net income per share of $0.13 to $0.15 (up from $0.05 per share this time last year). Even so, Wall Street's consensus estimates are slightly more optimistic, calling for earnings at the high end of that range and revenue slightly above the midpoint at $110.8 million.

On macro issues, large customers
You might be forgiven, then, if you're a little apprehensive to hear what InvenSense has accomplished over the past quarter. But don't be just yet.

During last quarter's subsequent conference call -- and this could explain Wall Street's elevated expectations -- CFO Mark Detinger made it clear their guidance was largely due to an abundance of caution with the macroeconomic environment.

"We are a little concerned with the macro issues we are hearing about," Detinger explained. "Some of it is China growth, some with the consumer sentiment coming out of the United States." 

In addition, keep in mind InvenSense also disclosed three large customers last quarter accounted for 38%, 23%, and 10% of total sales, respectively. That number was up from two large customers in the prior quarter -- namely, Apple at 32% and Samsung at 29% of sales -- indicating a third unnamed OEM joined the fold. Apple's share will likely continue to play an outsized role this quarter; InvenSense was recently confirmed to be supplying the high-end integrated 6-axis gyroscope and accelerator combination for the iPhone 6s.

But while it's great news that InvenSense's market-leading products are seeing continued success appealing to larger OEMs, these customers also receive volume discounts smaller businesses simply couldn't command. Therefore, results are subject to pressure in the near term as these large customers weigh on both average selling prices and profitability.

On supplementary growth
As I mentioned earlier, however, InvenSense enjoys the potential to expand into other vertical markets through its OIS platform, which Abdi noted during the last call, continues to build momentum. Particularly in South Korea, InvenSense's OIS solutions have already been adopted in all major flagship smartphones, and could drive significant incremental revenue by winning spots in entry-level and medium-tier smartphones down the road. Listen for updates, then, on whether OIS has continued to gain steam.

But perhaps even more exciting -- and even more crucial to achieving profitable, long-term growth -- will be updates on InvenSense's new Firefly family of products, which represents the industry's first complete system-on-a-chip integrating MEMs sensors with multi-core sensor process, embedded ARM, memory, and InvenSense's open software architecture. Previously, InvenSense management expressed confidence FireFly could gain traction in particular with Chinese smartphone makers, relieving them of the burden of designing and building their own similar power-efficient sensor packages. So, based on FireFly's most recent progress, look for comments on when exactly the company anticipates the promising SoC to meaningfully contribute to revenue and earnings.

Finally, Detinger last quarter also hinted during the call of "very good signals" that InvenSense's margins would see improvement either toward the end of this fiscal year or the beginning of fiscal 2017. Of course, InvenSense investors at this point are already growing impatient, but it's also worth reiterating that its current guidance still calls for relatively healthy growth on a year-over-year basis. With shares trading at just 14 times next year's expected earnings -- and within an accelerometer's throw of 52-week lows -- any signs of improvement this week would go a long way toward appeasing that impatience and proving InvenSense's growth story remains intact. 

Steve Symington owns shares of Apple and InvenSense. The Motley Fool owns shares of and recommends Apple and InvenSense. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.