Fig. 2
From: Environment-Adaptable Fast Multi-Resolution (EAF-MR) optimization in large-scale RF-FPGA systems

An example of a large-scale RF-FPGA system with 63 bits of control: each of three tunable amplifiers in (a) has 21 bits of control. Each tunable amplifier with 21 bits of control is composed of three cascaded tunable amplifiers with 7 bits of control as shown in (b)