Low Distortion, High Speed Rail-to-Rail Input/Output Amplifier

The AD8027/AD8028 are high speed amplifiers with rail-to-rail input and output that operate on low supply voltages and are optimized for high performance and a wide dynamic signal range. The AD8027/AD8028 have low noise (4.3 nV/√Hz, 1.6 pA/√Hz) and low distortion (120 dBc at 1 MHz). In applications that use a fraction of or use the entire input dynamic range and require low distortion, the AD8027/AD8028 are ideal choices.

Many rail-to-rail input amplifiers have an input stage that switches from one differential pair to another as the input signal crosses a threshold voltage, which causes distortion. The AD8027/AD8028 have a unique feature that allows the user to select the input crossover threshold voltage through the DISABLE/SELECT pin (DISABLE/SELECT x in the 10-lead MSOP, hereafter referred to as DISABLE/SELECT throughout this data sheet). This feature controls the voltage at which the complementary transistor input pairs switch. The AD8027/AD8028 also have intrinsically low crossover distortion.

With their wide supply voltage range (2.7 V to 12 V) and wide bandwidth (190 MHz), the AD8027/AD8028 amplifiers are designed to work in a variety of applications where speed and performance are needed on low supply voltages. The high performance of the AD8027/AD8028 is achieved with a quiescent current of only 6.5 mA (typical) per amplifier. The AD8027/AD8028 have a shutdown mode that is controlled via the DISABLE/SELECT pin.

The AD8027/AD8028 are available in 8-lead SOIC, 6-lead SOT-23, and 10-lead MSOP packages. The AD8028WARMZ-R7 is an automotive grade version, qualified for automotive applications. See the Automotive Products section for more details. The AD8027/AD8028 family is designed to work over the extended temperature range of −40°C to +125°C.

Applications

* Filters

* ADC drivers

* Level shifting

* Buffering

* Professional video

* Low voltage instrumentation

* High speed

* 190 MHz, −3 dB bandwidth (G = +1)

* 100 V/µs slew rate

* Low distortion

* 120 dBc at 1 MHz SFDR

* 80 dBc at 5 MHz SFDR

* Selectable input crossover threshold

* Low noise

* 4.3 nV/√Hz

* 1.6 pA/√Hz

* Low offset voltage: 900 µV maximum

* Low power: 6.5 mA per amplifier supply current

* Power-down mode

* No phase reversal: VIN > |VS| + 200 mV

* Wide supply range: 2.7 V to 12 V

* Small packaging: 8-lead SOIC, 6-lead SOT-23, 10-lead MSOP

* Qualified for automotive applications (AD8028WARMZ-R7 only)