Optical Coupled Isolation Amplifiers Detect Small Electric Currents With High-Precision

Toshiba has just announced the launch of two new optical coupled isolation amplifiers with a delta-sigma AD converter. The new TLP7820 and TLP7920 can detect small electric current and voltage fluctuations with high-precision, and are suitable for use in industrial equipment applications, including inverters, servo amplifiers, robots and power supplies.

Factory automation equipment operates with a high degree of precision, requiring feedback to the microcontroller to be extremely accurate when it comes to the status of the phase current of the motor or the variation of the bus voltage. To meet these requirements, Toshiba has equipped the new photocouplers with a delta-sigma analog to digital converter at the input side, which enables the industry’s highest level of linearity^[1] (0.02 percent (typ.)@NL₂₀₀ for analog output products and 3LSB(typ.)@INL for digital output products).

The isolation amplifiers also secure a CMTI (Common-Mode Transient Immunity) value of 20kV/μs (typ.), enabling stable operation in electrically noisy environments making them suitable for motor control applications. Isolation is through an optical barrier with an isolation voltage of 5000Vrms (min.). Operating temperature range is -40 to +105 degrees C.

A choice of two package types is available: TLP7920/TLP7930 is supplied in an industry standard DIP8 package, and TLP7820/TLP7830 comes in a new, more compact SO8L package, which takes up 30 percent less board space and has a 40 percent lower profile.

Line-up and Key Specifications:

Analog output products

Digital output products