AD7994BRUZ-1

Overview

The AD7994BRUZ-1 is a 4-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 supply and supports standard, fast, and high-speed I2C modes up to 3.4 MHz. The device includes a track-and-hold amplifier handling input frequencies up to 11 MHz and offers a throughput rate of 188 kSPS at 5 V. Key specifications include a signal-to-noise ratio of 71 dB, integral nonlinearity of ±1 LSB, and differential nonlinearity of +1/–0.9 LSB. It provides pin-selectable addressing via the AS pin and features an out-of-range alert function.

Feature Summary

• Supports standard, fast, and high-speed I2C communication modes for flexible bus integration.
• Includes programmable limit registers with an open-drain alert output for out-of-range detection.
• Features automatic shutdown between conversions to minimize power consumption.

Applications

• Battery-powered instrumentation systems requiring low power operation
• Industrial process control monitoring
• Data acquisition systems with multiple sensor inputs

Procurement Notes

Verify the ordering suffix '-1' confirms support for high-speed I2C mode up to 3.4 MHz, distinguishing it from the '-0' variant which is limited to 400 kHz. Confirm the 'B' suffix indicates the extended temperature range of -40°C to +125°C. Ensure the TSSOP-16 package matches the target PCB footprint.

Selection Notes

Select this component when a 12-bit resolution is required alongside multi-channel capability on a single chip. The AD7994BRUZ-1 is suitable for designs needing high-speed I2C interfaces or where pin-selectable addressing allows multiple devices on one bus without external hardware changes. Consider the external reference requirement if system accuracy demands precise voltage regulation.

Part Context

This part belongs to the AD7993/AD7994 family of low-power, 4-channel ADCs. The AD7994 specifically provides 12-bit resolution, whereas the AD7993 offers 10-bit resolution. Both share similar architectures but differ in accuracy and dynamic performance metrics.

Replacement Considerations

The AD7994BRUZ-0 serves as a functional substitute if high-speed I2C mode is not required, as it supports only standard and fast modes. The AD7993BRUZ-1 is an alternative if 10-bit resolution is sufficient.

FAQ

How does the AS pin affect the I2C address?

The AS pin allows pin-selectable addressing. For the AD7994-1, connecting AS to GND sets the address to 010 0011, while connecting it to VDD sets it to 010 0100. Leaving it floating results in the address 010 0000.

What is the maximum SCL frequency supported by the AD7994BRUZ-1?

The AD7994BRUZ-1 supports high-speed I2C mode, allowing an SCL frequency up to 3.4 MHz, provided the bus capacitance is within specified limits.

Can the internal reference be used?

No, the AD7994 requires an external reference voltage applied to the REFIN pin, which must be in the range of 1.2 V to VDD.