The OPA1611 (single) and OPA1612 (dual) bipolar-input operational amplifiers achieve very low 1.1nV/√Hz noise density with an ultralow distortion of 0.000015% at 1kHz. The OPA1611 and OPA1612 offer rail-to-rail output swing to within 600mV with a 2kΩ load, which increases headroom and maximizes dynamic range. These devices also have a high output drive capability of ±30mA.