Large-bandwidth, low-operation-voltage, and uniform organic amplifiers are fabricated on ultrathin foils. By the integration of short-channel OTFTs and AlOx capacitors, organic amplifiers with a bandwidth of 25 kHz are realized, demonstrating the highest gain-bandwidth product (GBWP) reported to date. Owing to material and process advancements, closed-loop architectures operate at frequencies of several kilohertz with an area smaller than 30 mm(2).