AD7894AR-10

Overview

The AD7894AR-10 is a fast, 14-bit successive approximation analog-to-digital converter housed in an 8-lead SOIC package. It operates from a single +5 V supply and features an on-chip track/hold amplifier, internal clock, and high-speed serial interface. The device accepts bipolar analog input signals ranging from -10 V to +10 V. Key electrical specifications include a maximum conversion time of 5 µs in Mode 1 operation, a typical power dissipation of 20 mW, and a signal-to-noise ratio of 77 dB. It supports throughput rates up to 160 kHz and includes an automatic power-down mode for low-power applications.

Feature Summary

• Integrated signal scaling circuitry allows direct interfacing with ±10 V analog inputs while operating from a single +5 V supply.
• High-speed two-wire serial interface enables efficient data transfer using standard SCLK and SDATA lines.
• On-chip track/hold amplifier ensures accurate sampling with a bandwidth exceeding the Nyquist rate at maximum throughput.
• Automatic power-down mode reduces energy consumption by entering standby after conversion completion.

Applications

• Battery-powered portable instrumentation requiring low power consumption
• Industrial process control systems utilizing bipolar voltage signals
• Data acquisition systems requiring 14-bit resolution and high sampling rates

Procurement Notes

Verify that the specific part number matches the required input range specification, as the AD7894 series includes variants for different voltage ranges. Confirm the package type is the 8-lead Narrow Body SOIC. Ensure the temperature grade corresponds to the commercial range of -40°C to +85°C. Check for RoHS compliance status if environmental regulations apply to the end product.

Selection Notes

Select this component when a single-supply ADC is needed for bipolar signals without external rail generation. Compare against the AD7895 if 12-bit resolution is sufficient, noting the pin compatibility. Consider the AD7894BR-10 variant if tighter integral nonlinearity specifications are required. Evaluate system throughput requirements against the 160 kHz limit determined by conversion and read times.

Part Context

The AD7894AR-10 belongs to the AD7894 family of 14-bit serial ADCs manufactured by Analog Devices. It serves as a pin-compatible upgrade to the 12-bit AD7895, offering higher resolution in the same compact package. The 'AR' suffix indicates the A-version temperature range and SOIC packaging, while '-10' designates the ±10 V input capability.

Replacement Considerations

The AD7894BR-10 is a confirmed substitute within the same family, offering identical functionality but with improved linearity specifications (INL ±1.5 LSB vs ±2 LSB). Both parts share the same pinout and input range.