Zero Drift, High Voltage, Low Power, Programmable Gain Instrumentation Amplifier

The ADA4254 is a zero drift, high voltage, low power programmable gain instrumentation amplifier (PGIA) designed for process control and industrial applications. The ADA4254 features 12 binary weighted gains ranging from 1/16 V/V to 128 V/V and three scaling gain options of 1 V/V, 1.25 V/V, and 1.375 V/V, resulting in 36 possible gain settings. The power consumption of the ADA4254 is a mere 22 mW, making the device an excellent choice for industrial systems that demand precision, robustness, and low power.

The zero drift amplifier topology of the ADA4254 self calibrates dc errors and low frequency 1/f noise, achieving excellent dc precision over the entire specified temperature range. This high level of precision maximizes dynamic range and greatly reduces calibration requirements in many applications.

The input multiplexer provides ±60 V protection to the high impedance inputs of the amplifier, while providing the capability to switch between two input sources. In addition, integrated electromagnetic interference (EMI) filters block harsh RF noise from the sensitive inputs of the amplifier.

Various safety features on the ADA4254 detect both internal and external faults. The serial port interface (SPI) supports cyclical redundancy check (CRC) error detection to ensure robust communication. These safety features ease system safety integrity level (SIL) certification.

Seven general-purpose input/output (GPIO) pins, which can be configured to provide various special functions, are included in the ADA4254. An excitation current source output is available to bias sensors such as resistance temperature detectors (RTDs).

The ADA4254 is specified over the −40°C to +105°C temperature range and is offered in a compact 5 mm × 5 mm, 28-lead LFCSP and a 24-lead TSSOP.

Applications

* Universal process control front ends

* Data acquisition systems

* Test and measurement systems

* Optimized for ADC synchronization

* Low power: 22 mW (±12 V supplies)

* 12 binary gain steps from 1/16 V/V to 128 V/V

* 3 scaling gains: 1 V/V, 1.25 V/V, and 1.375 V/V

* ±60 V protected input multiplexer

* Excellent dc precision

* Low input offset voltage: ±14 μV maximum

* Low input offset voltage drift: ±0.08 μV/°C maximum

* Gain calibration via ROM

* Low gain drift: ±1 ppm/°C maximum

* High CMRR: 116 dB minimum, G = 1 V/V

* Low input bias current: ±1.5 nA maximum

* High input impedance