AD7898AR-3

Overview

The AD7898AR-3 is a 12-bit successive approximation analog-to-digital converter housed in an 8-lead SOIC package. It operates from a single 5 V supply and achieves throughput rates up to 220 kSPS. The device features an on-chip track/hold amplifier and a flexible serial interface compatible with 3 V processors via the VDRIVE pin. The AD7898-3 variant supports a bipolar input voltage range of ±2.5 V. Key specifications include a maximum power dissipation of 22.5 mW, a conversion time of 3.3 µs in Mode 0, and a signal-to-noise ratio of 71 dB minimum.

Feature Summary

• Single 5 V supply operation with low power consumption suitable for battery-powered applications.
• Flexible high-speed serial interface allowing direct connection to 3 V or 5 V processor systems.
• On-chip track/hold amplifier ensures accurate sampling of analog signals.
• Integrated power-down mode significantly reduces current draw during idle periods.

Applications

• Portable instrumentation requiring low power and small form factor.
• Industrial process control systems utilizing serial communication.
• Data acquisition systems interfacing with microcontrollers.

Procurement Notes

Verify the specific ordering suffix to confirm package type and lead-free status. Ensure the selected variant matches the required input voltage range, as the -3 suffix denotes a ±2.5 V range. Confirm RoHS compliance if environmental regulations apply, noting that non-Z suffixes may not be lead-free. Check temperature range specifications against operational requirements.

Selection Notes

Select the AD7898AR-3 when a ±2.5 V input range is required rather than the ±10 V range offered by other variants. Consider the operating mode: Mode 0 uses an internal clock for simpler interfaces, while Mode 1 allows external clocking and power-down capabilities. Ensure the system can accommodate the 8-lead SOIC package dimensions and thermal characteristics.

Part Context

The AD7898 belongs to Analog Devices' family of fast, low-power ADCs designed for space-constrained applications. It integrates signal scaling, track/hold, and serial logic into a compact 8-lead package. This integration reduces component count compared to discrete solutions, offering significant board space savings while maintaining high performance metrics.

Replacement Considerations

The AD7894 series serves as a pin-compatible upgrade offering 14-bit resolution. For similar 12-bit performance, verify compatibility with existing circuit designs when substituting variants within the AD7898 family.