AD8322ARU

Supply Voltage +V _S
Pins 6, 8, 9, 20, 21, 23, 27 . . . . . . . . . . . . . . . . . . . . . . . 6 V
Input Voltages
Pins 25, 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.5 V
Pins 1, 2, 3, 7 . . . . . . . . . . . . . . . . . . . . . . . 0.8 V to +5.5 V
Internal Power Dissipation
TSSOP (RU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.90 W
Operating Temperature Range . . . . . . . . . . . 40°C to +85°C
Storage Temperature Range . . . . . . . . . . . . 65°C to +150°C
Lead Temperature, Soldering 60 seconds . . . . . . . . . . . 300°C

The AD8322 is a low-cost, digitally controlled variable gain amplifier optimized for coaxial line driving applications such as cable modems that are designed to the MCNS-DOCSIS upstream standard. An 8-bit serial word determines the desired output gain over a 42.14 dB range, with gain steps of 6.02 dB/major
carry.

The AD8322 comprises a digitally controlled variable attenuator of 0 dB to 42.14 dB, which is preceded by a low-noise, fixed-gain buffer and is followed by a low-distortion, high-power amplifier. The AD8322 accepts a differential or single-ended input signal. The output is specified for driving a 75 load, such as coaxial cable.

Distortion performance of 58 dBc is achieved with an output level up to 60 dBmV at 21 MHz bandwidth. A key performance and cost advantage of the AD8322 results from the ability to maintain a constant 75 output impedance during power-up and powerdown conditions. This eliminates the need for external 75 termination resulting in twice the effective output voltage when  compared to a standard operational amplifier.

The AD8322 is packaged in a low-cost 28-lead TSSOP, operates from a single 5 V supply, and has an operational temperature  range of 40°C to +85°C.