AD7998BRU-1

Overview

The AD7998BRU-1 is an 8-channel, 12-bit successive approximation analog-to-digital converter (ADC) featuring an I2C-compatible serial interface. It operates from a single 2.7 V to 5.5 V power supply and supports standard, fast, and high-speed I2C modes up to 3.4 MHz. The device includes an 8-channel multiplexer with a track-and-hold amplifier capable of handling input frequencies up to 11 MHz. Key specifications include a typical conversion time of 2 µs, a throughput rate of up to 188 kSPS, and a signal-to-noise ratio of 71 dB. It offers low power consumption with a shutdown mode current of 1 µA maximum.

Feature Summary

• Supports standard, fast, and high-speed I2C communication modes for flexible bus integration.
• Integrates an 8-channel multiplexer and track-and-hold amplifier for efficient multi-point sampling.
• Features programmable limit registers with an open-drain out-of-range alert output function.
• Utilizes pin-selectable addressing via the AS pin to allow multiple devices on a single serial bus.

Applications

• Battery-powered instrumentation systems requiring low power consumption.
• Industrial process control loops utilizing I2C-based data acquisition.
• Portable medical equipment needing multi-channel signal conditioning.
• Automotive sensor interfaces operating within wide voltage ranges.

Procurement Notes

Verify the specific suffix '1' indicates support for high-speed I2C modes up to 3.4 MHz, distinguishing it from the '-0' variant which is limited to standard and fast modes. Confirm the package type is 20-lead TSSOP and check RoHS compliance status as per the manufacturer's latest documentation before finalizing orders.

Selection Notes

Select this component when eight single-ended analog inputs are required with 12-bit resolution. Ensure the system clock frequency supports the desired throughput rate, noting that higher speeds increase power consumption. Verify that the external reference voltage range accommodates the application's input signal span, as the REFIN pin accepts voltages from 1.2 V to VDD.

Part Context

This part belongs to the AD7997/AD7998 family of low-power ADCs. The AD7998 provides 12-bit resolution, whereas the AD7997 offers 10-bit resolution. Both share similar architectures but differ in accuracy and dynamic performance metrics. Equivalent devices with fewer channels include the AD7992 (2-channel) and AD7994 (4-channel).

Replacement Considerations

The AD7998BRUZ-0 serves as a functional alternative if high-speed I2C mode is not required. For lower resolution needs, the AD7997 series may be considered. Ensure pin compatibility and software register mapping remain consistent when substituting within the same product family.