HCPL-7840 Datasheet | Broadcom

Isolation Amplifier Data Sheet Description The Broad® HCPL-7840 isolation amplifier family is designed for current sensing in electronic motor drives. In a typical implementation, motor currents flow through an external resistor and the resulting analog voltage drop is sensed by the HCPL-7840. A differential output voltage is created on the other side of the HCPL-7840 optical isolation barrier. This differential output voltage is proportional to the motor current and can be converted to a single-ended signal by using an op-amp as shown in the remended application circuit. Since mon-mode voltage swings of several hundred volts in tens of nanoseconds are mon in modern switching inverter motor drives, the HCPL-7840 was designed to ignore very high mon-mode transient slew rates (of at least 10 k V/μs). The high CMR capability of the HCPL-7840 isolation amplifier provides the precision and stability needed to accurately monitor motor current in high noise motor control environments, providing for smoother control (less torque ripple) in various types of motor control applications. The product can also be used for general analog signal isolation applications requiring high accuracy, stability, and linearity under similarly severe noise conditions. For general applications, we remend the HCPL-7840 (gain tolerance of ±5%). The HCPL-7840 uses sigma-delta (Σ-Δ) analog-to-digital converter technology, chopper stabilized amplifiers, and a fully differential circuit topology fabricated using the Broad 0.8-μm CMOS IC process. Together, these Features deliver unequaled isolation mode noise rejection, as well as excellent off set and gain accuracy and stability over time and temperature. This performance is delivered in a pact, auto-insertable, industry-standard 8-pin DIP package that meets worldwide regulatory safety standards. (A gull-wing surface mount option #300 is also available.) Features - 15 k V/μs mon-mode rejection at VCM = 1000V -...