AD7778ASZ

Overview

The AD7778ASZ is an LC2MOS high-speed analog-to-digital converter featuring eight channels and a 10-bit resolution. It operates within a temperature range of -40°C to +85°C and utilizes a 44-lead PQFP package. The device supports a maximum sampling rate of 378 kHz with a clock input frequency up to 2 MHz. It requires a single +5 V power supply and includes an internal voltage reference output nominally set at 2.0 V. Dynamic performance specifications include a minimum signal-to-noise and distortion ratio of -56 dB and total harmonic distortion of -60 dB under standard test conditions.

Feature Summary

• Supports simultaneous sampling and sequential conversion for two selected channels via control register configuration.
• Integrates a track-and-hold amplifier capable of processing signals up to the Nyquist frequency.
• Features a configurable BUSY/INT status output that indicates conversion completion or active processing states.
• Includes a dedicated power-down mode that disables linear circuitry to minimize current consumption.

Applications

• Digital signal processing systems requiring voice recognition or echo cancellation
• Adaptive filtering applications in communication infrastructure
• Multiplexed data acquisition systems utilizing DSP machines or microcontrollers

Procurement Notes

Verify the specific ordering suffix ASZ corresponds to the PQFP package option when sourcing components. Confirm that the required temperature grade matches the A version specifications for industrial environments. Ensure that the design accommodates the specified logic voltage levels and power supply requirements for reliable operation.

Selection Notes

Select this component for applications requiring multiple synchronized analog inputs with moderate resolution. Evaluate the interface timing constraints against the target processor's bus speed to ensure proper data capture. Consider the power-down functionality if system energy efficiency during idle periods is a critical design parameter.

Part Context

This part belongs to the AD7776/AD7777/AD7778 family of high-speed ADCs manufactured by Analog Devices. The family differentiates primarily by channel count, with the AD7778 providing eight inputs compared to one or four in other variants. All members share identical core architecture, control logic, and dynamic performance characteristics.

Replacement Considerations

Direct functional substitutes within the same family include the AD7776AR for single-channel needs and the AD7777AN or AD7777AR for four-channel configurations. These alternatives maintain compatible pinouts and control registers but differ in the number of available analog input channels.