LMH6645

LMH6645/46/47 2.7V, 650µA, 55MHz, Rail-to-Rail Input and Output Amplifiers with Shutdown Option February 2002 LMH6645/46/47 2.7V, 650µA, 55MHz, Rail-to-Rail Input and Output Amplifiers with Shutdown Option General Description The LMH6645 (single) and LMH6646 (dual), rail-to-rail input and output voltage feedback amplifiers, offer high speed (55MHz), and low voltage operation (2.7V) in addition to micro-power shutdown capability (LMH6647, single). Input common mode voltage range exceeds either supply by 0.3V, enhancing ease of use in multitude of applications where previously only inferior devices could be used. Output voltage range extends to within 20mV of either supply rails, allowing wide dynamic range especially in low voltage applications. Even with low supply current of 650µA/amplifier, output current capability is kept at a respectable ± 20mA for driving heavier loads. Important device parameters such as BW, Slew Rate and output current are kept relatively independent of the operating supply voltage by a combination of process enhancements and design architecture. In portable applications, the LMH6647 provides shutdown capability while keeping the turn-off current to less than 50µA. Both turn-on and turn-off characteristics are well behaved with minimal output fluctuations during transitions. This allows the part to be used in power saving mode, as well as multiplexing applications. Miniature packages (SOT23, MSOP-8, and SO-8) are further means to ease the adoption o...