AD7896JR

Overview

The AD7896JR is a 12-bit successive approximation register (SAR) analog-to-digital converter manufactured by Analog Devices Inc. It operates from a single 2.7 V to 5.5 V supply and features an on-chip track-and-hold amplifier, internal clock, and high-speed serial interface. The device accepts a unipolar analog input range of 0 V to VDD, utilizing the supply voltage as the reference. It delivers a throughput rate of 100 kHz with an 8 µs conversion time in high sampling mode. Typical power consumption is 9 mW, supporting low-power applications.

Feature Summary

• Integrates a 12-bit SAR ADC, track-and-hold amplifier, and serial interface logic within an 8-lead package.
• Operates from a single 2.7 V to 5.5 V supply without requiring an external voltage reference.
• Features a proprietary automatic power-down mode that activates after conversion completion to minimize energy usage.

Applications

• Battery-powered portable instrumentation
• Industrial data acquisition systems
• Process control monitoring

Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm the specific J version temperature rating matches operational requirements. Check for obsolescence status and lead times due to potential discontinuation. Ensure ESD precautions are observed during handling and installation.

Selection Notes

Select this component for applications requiring a compact 12-bit resolution with a single-supply operation. The J version is suitable for commercial temperature ranges. Consider the auto-sleep mode for battery efficiency if lower throughput rates are acceptable. Verify interface compatibility with the host microcontroller's serial clock capabilities.

Part Context

The AD7896JR belongs to the AD7896 family of fast, 12-bit ADCs. It is distinct from other variants like the AD7896ANZ or AD7896ARZ primarily by its packaging and specified operating temperature range. The 'JR' suffix indicates the SOIC package and commercial temperature grade.

Replacement Considerations

The AD7896JR is obsolete. The AD7896JRZ is listed as a direct replacement. Verify pinout and electrical specifications match before substitution.

FAQ

How is the analog reference voltage determined?

The AD7896 uses the VDD supply voltage as its internal reference, eliminating the need for an external reference component.

What is the maximum serial clock frequency?

The maximum serial clock frequency is 10 MHz, which allows for optimal throughput performance at higher supply voltages.

How does the automatic power-down mode function?

In Mode 2 operation, the device enters power-down automatically when CONVST is low after conversion. It wakes up upon the rising edge of the next CONVST pulse.