The OPA835 and OPA2835 from Texas Instruments are ultra-low-power, rail-to-rail output, voltage-feedback (VFB) operational amplifiers. Designed for high-performance applications, these single (OPA835) and dual (OPA2835) op-amps operate over a power supply range of 2.5 V to 5.5 V. Consuming a mere 250 µA per channel, they offer a remarkable balance of power efficiency and performance, boasting a unity-gain bandwidth of 56 MHz, a slew rate of 160 V/µs, and ultra-low THD of 0.00003% at 1 kHz. Key features include a large signal bandwidth, negative rail input, power-down mode reducing current to 0.5 µA, and input voltage noise of 9.3 nV/√Hz at 100 kHz. Packaged options such as SOT-23, QFN, SOIC, VSSOP, and UQFN are available, accommodating a range of design requirements. The devices are ideal for battery-powered and portable applications, offering superior performance-to-power ratios for high-frequency amplifiers.