An 850 MHz current feedback operational amplifier

A monolithic DC-to-850 MHz, low-distortion current feedback operational amplifier fabricated in a complementary bipolar bonded wafer technology is described. Discussed are an approach for achieving low-input offset voltage without sacrificing common-mode range or gain bandwidth; design for expected package and board parasitics; the use of low-overhead, high-impedance signal mirrors in the gain stage; and inverting input bias current cancellation. The output clamp is described. A summary of the circuit's performance obtained from production and bench testing on multiple fabrication lots is presented.<>