AD7715AN-3

Overview

The AD7715AN-3 is a complete analog front end for low frequency measurement applications, featuring a 16-bit Sigma-Delta ADC with no missing codes. It operates from a single 3 V supply (AVDD) and accepts differential inputs directly from transducers. The device includes a programmable gain front end with gains of 1, 2, 32, and 128, and an on-chip digital filter with programmable output update rates. It utilizes a three-wire serial interface compatible with SPI, QSPI, Microwire, and DSP systems. The component is housed in a 16-lead PDIP package and supports unipolar or bipolar input signal ranges.

Feature Summary

• Integrates a charge-balancing ADC with a programmable gain front end to accept low-level signals directly from sensors.
• Features an on-chip digital filter with programmable notch frequencies to adjust cutoff and output update rates.
• Includes self-calibration and system calibration options to eliminate gain and offset errors.
• Supports multiple serial interface protocols including SPI, QSPI, Microwire, and DSP compatibility.

Applications

• Smart transmitters
• Pressure measurement systems
• Temperature measurement systems

Procurement Notes

Verify the specific suffix 'AN' indicates the Analog Devices PDIP package variant. Confirm the '-3' designation aligns with the required 3 V analog supply voltage specifications. Ensure the application environment remains within the specified operating temperature range for the A version. Cross-reference the datasheet revision to confirm pinout and electrical characteristics match the design requirements.

Selection Notes

Select this component when a single-channel, low-power, high-precision ADC is required for low-frequency sensor interfaces. The 3 V operation makes it suitable for battery-powered systems. Consider the available gain settings and digital filter configurations to match the specific noise and bandwidth requirements of the target application without external conditioning.

Part Context

The AD7715 belongs to the AD7715 series of low-frequency analog front ends manufactured by Analog Devices. This family integrates signal conditioning and conversion capabilities into a single CMOS chip. The AD7715AN-3 specifically denotes the through-hole PDIP package variant designed for 3 V operation, distinguishing it from the 5 V variants and surface-mount packages.

Replacement Considerations

Public confirmed substitute part numbers are not provided in the verified source material.

FAQ

What clock frequencies does the AD7715 support?

The AD7715 is guaranteed to operate with a master clock frequency between 400 kHz and 2.5 MHz. Production testing is typically performed at 2.4576 MHz.

How does the AD7715 handle calibration?

The device contains on-chip registers that allow for software-controlled self-calibration and system calibration. These functions eliminate zero-scale and full-scale errors caused by the part itself or the system.

Can the AD7715 buffer the analog input?

Yes, the AD7715 features the ability to buffer the analog input, which can be configured via the setup register to improve performance with certain sensor types.