When it comes to mobile chips, Qualcomm (Nasdaq: QCOM) is in an enviable position -- although you couldn't tell by looking at today's action following second-quarter earnings. Shares are in the red to the tune of 6% as of this writing; what gives?

What's not to like?
Let's start with the basics. Top-line revenue jumped 28% to $4.94 billion, with adjusted earnings per share of $1.01. Both figures represented record quarterly results for the company, while also beating analysts' best guesses.

The Street was looking for $4.82 billion up top and $0.95 per share down below. The bottom line also came in on top of Qualcomm's own guidance, which had estimated earnings between $0.91 and $0.97 per share.

Free cash flow ticked down slightly by 2% to $1.8 billion, while operating income rose 15% to $1.9 billion. The company also recently boosted its quarterly dividend to $0.25 per share, with the new payout starting next quarter.

MSM chip shipments, which include Qualcomm's popular Snapdragon mobile processors, among other things, jumped 29% to 152 million. In the quarter ending in December, there were an estimated 239 million to 243 million 3G and 4G devices shipped, with an average selling price, or ASP, between $211 and $217, all of which are healthy improvements from the figures seen a year ago.

Qualcomm's CDMA technologies segment, or QCT, was the real growth driver here. The segment's revenue jumped 56%, while Qualcomm's other smaller divisions were essentially flat.

By just about any metric, this was an impressive quarter, as Qualcomm's mobile-centric businesses continue to shine.

Guidance will get you
It never ceases to amaze me when a company's relatively soft guidance in the short run can negate all of the overwhelming positives contained in the rest of an earnings release, and that's exactly the case here.

In the coming quarter, revenue is expected to be in the ballpark of $4.45 billion to $4.85 billion, and earnings per share should be $0.83 to $0.89. Mr. Market says that's not good enough, as it was expecting third-quarter revenue of $4.8 billion with profit of $0.90 per share.

We can ignore the part about Qualcomm's raising of its full-year profit outlook, though; we're just focusing on the negative, remember? At least that's what investors are doing today.

The culprit behind the conservative forecast is supply constraints stemming from manufacturing partner Taiwan Semiconductor Manufacturing (NYSE: TSM). The demand is there -- and booming -- but Qualcomm is having trouble keeping up. CEO Paul Jacobs told The Wall Street Journal, "Chasing supply is our biggest issue."

More specifically, the problems relate to 28-nanometer manufacturing, which TSMC continues to ramp up. On the conference call, Jacobs said:

Although the manufacturing yields are progressing per expectation, there's a shortage of 28-nanometer capacity. And at this stage, we cannot secure enough supply to meet the increasing demand we're experiencing. We're working closely with our partners to bring additional capacity online. However, the constraints on 28-nanometer supply are limiting our potential revenue upside this fiscal year.

Source: Qualcomm Q2 2012 earnings conference call.

However, he expects the situation to improve significantly toward the tail end of the year. It's worth mentioning that this is exactly the same problem that rival chipmaker NVIDIA (Nasdaq: NVDA) is facing with TSMC as well.

This is one of the weaknesses of the fabless semiconductor model, as these companies rely heavily on manufacturing partners and have to compete for available supply. Intel (Nasdaq: INTC) is quietly laughing behind the scenes as it enjoys its vertical integration.

Chip King Kong's Ivy Bridge chips this year are already down to a 22-nanometer process -- although Intel's Medfield Atom mobile chips, that will compete with Qualcomm's Snapdragons, are still on 32-nanometer.

Just because the Street loses sleep, that doesn't mean you have to
Manufacturing hurdles aside, Qualcomm is still one of a kind in mobile chips. Its baseband dominance is exemplified by its wins in Apple (Nasdaq: AAPL) iDevices -- both the iPhone 4S and third-generation 4G LTE iPad carry Qualcomm modems.

Apple has slowly been transitioning to Qualcomm as the sole supplier of its baseband chips, after ditching Infineon -- just after Intel bought its wireless division, no less. Infineon's last Apple win was the 3G iPad 2 for AT&T, while the Verizon flavor went to Qualcomm.

Last year, the company carried an estimated 43% market share of baseband processors and 50% of the application processors market.

Long-term Fools, this is your chance to get a deal on a company with a unique role in the mobile supply chain as the Street loses sleep over the next few fiscal quarters. "Be greedy when others are fearful."

Qualcomm's earnings are out of the bag, but there are still another 5 Stocks Investors Need to Watch This Earnings Season, including one tech darling mentioned in this report. These companies need to be on your radar, if they're not already. Get the free report now.