Overall, we believe we are doing good job controlling operating expenses while managing the significant growth we have achieved during the past several quarters. As the result, our second quarter operating margin expanded to 25.8%.
In addition, our share focus on working capital management continues to result an improvement in many of the key balance sheet metrics. During the second quarter, cash and short-term investments increased by nearly 21 millions to a balance of $104 million. Our second quarter cash flow from operations increased to nearly 27 million up significantly from approximately 18 million in the prior quarter.
Given our strong financial position, we are aggressively reinvesting in our business. R&D activates have resulted in the significant number of new products introductions that has significantly expanded our sales addressable market to include high growth opportunities in digital televisions, display backlight drivers, 3G and 4G communication network, computing and automotive, the named other few. We also remain focused on enhancing shareholder value and we announced in the press release this afternoon, we maintain our quarterly $0.035 cent per share dividend and continue to by back stocks through stock repurchases which more than offset dilution of stock option purchases.
With that let's now move on to closer look at Micrel second quarter financial details. Revenue in quarter totaled 73.9 million compared to 67.2 million in first quarter of 2010 and 51.8 million in the year ago period. To reiterate, the 10% sequential growth in the quarter was slightly below expectations primarily due to delinquencies within our supply chain had delayed some of our product shipments in the quarter, compared to the same period last year, revenues were higher by 22.1 million or 42.7% due to over -- high overall demands from customers in all geographies and end market as a result and the global recovery from the recent world wide economic slow down.Read the rest of this transcript for free on seekingalpha.com