Analog Devices, Inc. has introduced two multi-channel +/-10V and 0-20mA precision A/D converters that better enable implementation of programmable logic controller (PLC) and distributed control system (DCS) modules. Leveraging ADI’s iPassives integrated precision passives technology, the AD4111 and AD4112 A/D converters integrate precision matched current sense resistors and resistor dividers. The high degree of channel-to-channel matching simplifies calibration requirements, and with support for up to eight single-ended voltage inputs and four current inputs, makes the new products ideal for use as reconfigurable platform solutions, while reducing size, complexity and cost in PLC and DCS modules.
The AD4111 and the AD4112 A/D converters can accept +/-10V while meeting performance specifications and has a functional range of +/-20V, adding over-range margin to the nominal +/-10V. They can also accept currents of -0.5 to 24mA while meeting performance specifications. This allows reliable measurements close to 0mA and provides over range margin past 20mA. The devices offer an Absolute Maximum Rating of +/-50V on voltage pins and +/-50mA on current pins. The AD4111 uniquely enables open wire detection, to detect when an external sensor or signal source is disconnected from the system input, on +/-10V voltage inputs while operated from either a +5V or +3.3V single power supply.
AD4111 Product Highlights:
- Single 3.3V or 5V supply
- Single design supports both voltage and current inputs
- Integration of precision matched current sense resistor and resistor dividers
- +/-10V specified input voltage range and +/-20V functional input voltage range
- >1Mohm input impedance
- Enables open-wire detection
