The recession and AdMob haven’t been formally introduced it seems. The mobile ad firm just closed $15.7 million in a third round of funding and says it has become cash-flow positive. The funding was led by Sequoia Capital’s Growth Fund with Accel Partners also participating. Sequoia also led first $4 million round of funding and Accel led in the company’s second round of $15 million. AdMob has now raised a total of $34.7 million in three rounds in about two years. The new pool of money is being used to recruit sales and other staff in markets that have grown faster than expected like India and South Africa. AdMob currently has about 80 employees (half of which are engineers) and expects to surpass 100 by the end of the first quarter in 2009. Its business model calls for up to 150 employees by the end of 2009. More investment will be made in Western Europe, Japan and the company’s platform including targeting and ad-serving algorithms.

A spokesman said the company is effectively doubling down and gearing up to prepare for competition from the likes of AOL (NYSE: TWX) and Microsoft (NSDQ: MSFT). It’s a strategy that runs contrary to what Sequoia told portfolio companies at a doom-and-gloom presentation last week where it urged companies to cut spending. Still, it’s worth noting that Sequoia’s stake in this round comes from its new nearly $1 billion “growth fund,” which is designed to help later-stage companies maintain growth in a tumultuous economy. Plus, mobile advertising is still in its infancy. While mobile ad requests and placements are rising, prices remain relatively low. For instance, the mobile advertising market is growing, but currently in the U.S., it only amounts to an $800 million industry, which works out to be just about .4 percent of the entire advertising pie, according to analyst Chetan Sharma.

Disclosure: AdMob has been a sponsor of mocoNews

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