An extra-fast current feedback amplifier and a level discriminator are developed employing a dielectrically isolated bipolar, semicustom application-specific integrated circuit (ASIC) process. These devices are specifically designed for instruments aboard spacecraft or in portable packages requiring low power and weight. The amplifier adopts current feedback for a unity-gain bandwidth of 90 MHz while consuming 50 mW. The level discriminator uses a complementary output driver for balanced positive and negative response times. The power consumption of these devices can be programmed by external resistors for an optimal speed and power tradeoff. The circuit behaved satisfactorily in speed for radiation doses up to 5 Mrd. The design of the ASICs can be performed easily on an IBM-PC-compatible computer using SPICE with manufacturer-supplied device libraries for various transistor geometries. >