Highest-Precision Reinforced Isolated Amplifier for Industrial Voltage-Sensing
Texas Instruments (TI) today introduced a new reinforced isolated amplifier that claims the industry’s highest precision and working voltages, and longest lifetime reliability. With exceptional performance that includes better nonlinearity, lower offset and gain error, and higher temperature stability, the ISO224 allows engineers to overcome performance limitations and design high-precision systems.
The new amplifier is designed for isolated voltage sensing in factory automation and control, grid infrastructure, rail transport and motor drive applications.
The input of the ISO224 is optimized for accurate sensing of ±10-V signals that are widely used in industrial applications. The device operates of a single supply on the high-side. This unique feature simplifies the design of the isolated power supply and reduces the system cost.
The integrated high-side supply voltage detection feature simplifies system level diagnostics. The ±4-V output of the ISO224 allows lower-cost analog-to-digital converters (ADCs) to be used. The differential structure of the output supports high immunity to noise.
TI’s capacitive isolation technology enables the longest lifetimes and 50 percent higher working voltages than required by isolation industry standards, common-mode transient immunity (CMTI) of up to 80kV/µs and robust operation over an extended industrial temperature range of -55°C to +125°C.
The high-precision ISO224 enables more accurate measurements of ±10-V signals, which are widely used in industrial applications, with 25 percent better nonlinearity, eight times lower gain error, lower offset drift and faster system response than similar competitive devices.
Engineers can reduce board space with the ISO224’s 60 percent smaller package than the previous-generation ISO12x amplifiers as well as its output that supports direct connection to an analog-to-digital converter with 5-V input. The ISO224 also features a single, high-side supply with integrated voltage detection that simplifies the design and system-level diagnostics.
Summary of features:
- Offered in High-Grade (ISO224B) and Low-Grade (ISO224A) Versions
- ±12-V Input Voltage Range Optimized for Isolated Voltage Measurement in Industrial Applications
- Overvoltage Input Clamp With 9-kV ESD
- ±4-V Differential Output Voltage Range with Common-Mode at VDD2 / 2
- Low DC-Error Operation (ISO224B):
- Input Offset: ±5mV at 25°C, ±42µV/°C max
- Gain Error: ±0.3% at 25°C, ±50ppm/°C max
- Nonlinearity: ±0.01% max, ±1ppm/°C
- 5-V to 18-V Single-Supply on High-Side
- 5-V to 5.5-V Operation on Low-Side
- Safety-Related Certifications:
- 7071-VPEAK Reinforced Isolation per DIN VDE V 0884-11:2017-01
- 5000-VRMS Isolation for 1 Minute per UL1577
- High CMTI: 140kV/µs (typ), 75kV/µs (min)
Designers can download the TINA-TI™ SPICE model and then simulate and analyze their circuit behavior with the ISO224 isolated amplifier by downloading the SIM TINA-TI reference design, the ISO224 TINA-TI SPICE model, or by using the ISO224 evaluation module.
Preproduction samples of the ISO224 are available now through the TI store. The ISO224 is available in an 8-pin, 5.85-mm-by-7.5-mm small-outline integrated circuit (SOIC) package. Pricing starts at US$6.49.