The ISL26132 and ISL26134 are complete analog front ends for high resolution measurement applications. These 24-bit Delta-Sigma Analog-to-Digital Converters include a very low-noise amplifier and are available as either two or four differential multiplexer inputs. The devices offer the same pinout as the ADS1232 and ADS1234 devices and are functionally compatible with these devices. The ISL26132 and ISL26134 offer improved noise performance at 10Sps and 80Sps conversion rates.

The on-chip low-noise programmable-gain amplifier provides gains of 1x/2x/64x/128x. The 128x gain setting provides an input range of ±9.766mVFS when using a 2.5V reference. The high input impedance allows direct connection of sensors such as load cell bridges to ensure the specified measurement accuracy without additional circuitry. The inputs accept signals 100mV outside the supply rails when the device is set for unity gain.

The Delta-Sigma ADC features a third order modulator providing up to 21.6-bit noise-free performance. The device can be operated from an external clock source, crystal (4.9152MHz typical), or the on-chip oscillator. The two channel ISL26132 is available in a 24 Ld TSSOP package and the four channel ISL26134 is available in a 28 Ld TSSOP package. Both are specified for operation over the automotive temperature range (-40°C to +105°C). 

Key Features

• Up to 21.6 Noise-free bits.
• Low Noise Amplifier with Gains of 1x/2x/64x/128x
• RMS noise: 10.2nV @ 10Sps (PGA = 128x)
• Linearity Error: 0.0002% FS
• Simultaneous rejection of 50Hz and 60Hz (@ 10Sps)
• Two (ISL26132) or four (ISL26134) channel differential input multiplexer
• On-chip temperature sensor (ISL26132)
• Automatic clock source detection
• Simple interface to read conversions
• +5V Analog, +5 to +2.7V Digital Supplies
• Pb-Free (RoHS Compliant)
• TSSOP packages: ISL26132, 24 pin; ISL26134, 28 pin

 Typical Applications

• Digital Multimeter
• Smart Sensor
• Toxic Gas Monitor
• Weigh Scale
• Temperature Monitors and Controls
• Industrial Process Control
• Pressure sensors

The ISL26134AV28EV1ZA  provides a means to evaluate the functionality and performance of the ISL26134 A/D converter. The board includes an AT90USB162 microcontroller with a USB interface.  The microcontroller interfaces to the ISL26134 ADC via a galvanically-isolated interface and provides serial communication via USB between the board and the PC. 

Software for the PC provides a GUI (graphical user interface) that allows the user to perform data capture, and then to process and plot of the results of the time domain analysis, the histogram analysis, and/or the frequency domain analysis on the captured data.  The GUI also enables the user to save conversion data from the ADC to a file, or to save the results of the analyzed conversion data.

Features

• Galvanically-isolated USB Communication with PC
• On-board microcontroller
• On-board voltage reference
• Evaluation Software
• Time Domain Analysis
• Noise Histogram Analysis
• FFT Analysis