AD7828BR

Overview

The AD7828BR is an 8-channel, 8-bit analog-to-digital converter manufactured by Analog Devices Inc. It utilizes a half-flash conversion architecture to achieve a fast conversion rate of 2.5 µs per channel. The device operates from a single 5 V supply and features a built-in track-and-hold function capable of handling input signals with frequencies up to 10 kHz. It employs a parallel digital interface controlled by Chip Select (CS) and Read (RD) signals, eliminating the need for an external clock. The BR variant supports an industrial operating temperature range of -40°C to +85°C and has a total unadjusted error specification of ±1 LSB.

Feature Summary

• Half-flash conversion technique enables high-speed digitization without requiring an external clock signal.
• Integrated track-and-hold circuitry allows direct acquisition of signals up to 10 kHz bandwidth.
• Parallel data bus with three-state outputs simplifies interfacing with standard microprocessors.
• Single 5 V power supply operation reduces system complexity and component count.

Applications

• Industrial process control systems requiring multi-channel sensor monitoring
• Speech analysis applications utilizing real-time band-pass filtering
• Fast infinite sample-and-hold circuits in data acquisition systems

Procurement Notes

Verify that the specific part number suffix corresponds to the required temperature grade and package option. Confirm that the design accommodates the single 5 V supply requirement and parallel interface timing constraints. Ensure proper decoupling capacitors are placed near the VDD pin to maintain signal integrity during switching events.

Selection Notes

Select this component when high throughput across multiple channels is prioritized over resolution. The 8-bit accuracy and 2.5 µs conversion time suit applications where latency is critical. Consider the parallel interface requirements if I/O pins are limited, as serial alternatives may offer fewer connection points.

Part Context

This device belongs to the AD7824/AD7828 family of high-speed multichannel ADCs. While the AD7824 offers four channels, the AD7828 provides eight multiplexed inputs. Both share identical internal architectures and timing characteristics, differing primarily in channel count and pin configuration within the 28-lead package options.

Replacement Considerations

The AD7828CQ serves as a parameter-equivalent alternative within the same family, offering improved linearity with a ±1/2 LSB total unadjusted error specification while maintaining identical electrical performance and interface compatibility.