AD7828KNZ

Overview

The AD7828KNZ is an 8-bit, 8-channel analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It utilizes a half-flash architecture to achieve a conversion rate of 2.5 µs per channel, supporting a sampling frequency of 50 kHz for each of its eight multiplexed single-ended inputs. The device operates from a single 5 V supply with typical power dissipation of 50 mW. It features a built-in track-and-hold function capable of handling input signals up to 10 kHz. The component is housed in a 28-lead plastic dual-in-line package (PDIP) and functions within a commercial temperature range of 0°C to 70°C.

Feature Summary

• Integrates an 8-channel analog multiplexer with a built-in track-and-hold circuit to eliminate the need for external sample-and-hold components.
• Employs a half-flash conversion technique using two 4-bit flash ADCs to provide fast 8-bit resolution without requiring an external clock signal.
• Features a simple microprocessor interface utilizing standard Chip Select and Read signals, allowing direct connection to popular processors like the Z80 or MC68000.

Applications

• Speech analysis systems utilizing real-time filtering
• Fast infinite sample-and-hold configurations
• Multichannel data acquisition systems

Procurement Notes

Verify the specific ordering suffix 'KNZ' against current manufacturer documentation to confirm availability and exact specifications. The 'K' grade indicates a commercial temperature range of 0°C to 70°C, while 'N' denotes the 28-lead DIP package. Confirm RoHS compliance status as manufacturing processes may evolve. Check for any product change notices regarding assembly or material composition updates prior to final design implementation.

Selection Notes

Select the AD7828KNZ when an 8-channel solution is required with a 50 kHz per-channel sampling rate. Ensure the application supports single-ended inputs within a 0 V to 5 V range relative to an external 5 V reference. This part is suitable for designs where a parallel interface is preferred over serial protocols and where a 28-pin through-hole footprint fits the board layout constraints.

Part Context

The AD7828KNZ belongs to the AD7824/AD7828 family of high-speed multichannel ADCs. It shares the same core half-flash architecture and operational characteristics as the 4-channel AD7824, differing primarily in the number of analog input channels and the corresponding package pin count. Both devices utilize the LC2MOS process for low power consumption and high speed.

Replacement Considerations

The AD7828LNZ serves as a higher accuracy alternative within the same package and temperature range, offering a total unadjusted error of ±1/2 LSB compared to the ±1 LSB of the KNZ variant. Other package options such as PLCC or SOIC are available under different ordering suffixes like KP or BR.