AD7828LP

Overview

The AD7828LP is an 8-channel, 8-bit analog-to-digital converter (ADC) utilizing a half-flash architecture. It operates on a single 5 V supply with a typical power dissipation of 50 mW. The device features a built-in track-and-hold function capable of handling signals up to 10 kHz. Conversion time is 2.5 µs per channel, allowing a maximum sampling rate of 50 kHz for the eight channels. Total unadjusted error is ±1/2 LSB max. It interfaces via standard Chip Select and Read signals without requiring an external clock. The LP variant provides ±1/2 LSB accuracy in the commercial temperature range of 0°C to +70°C.

Feature Summary

• Half-flash conversion technique eliminates the need for an external ADC clock signal.
• Built-in track-and-hold function supports high slew rate inputs up to 157 mV/µs.
• Standard microprocessor interface using Chip Select and Read control signals.
• Single 5 V supply operation simplifies system power requirements.

Applications

• Speech analysis systems utilizing real-time filtering
• Fast infinite sample-and-hold circuits
• Microprocessor-based data acquisition systems

Procurement Notes

Verify the specific suffix against the manufacturer's ordering guide to confirm the package option and temperature grade. Confirm that the component meets the required total unadjusted error specifications for the intended application environment. Check for availability as this part may be subject to discontinuation or limited stock status from distributors.

Selection Notes

Select the AD7828LN if a tighter total unadjusted error specification is required compared to the AD7828LP. Consider the AD7824 if only four analog input channels are necessary for the design. Ensure the driving source impedance does not exceed 100 Ω to maintain accuracy due to the internal sampling capacitance characteristics.

Part Context

The AD7828LP belongs to the AD7824/AD7828 family of high-speed multichannel ADCs. These devices are fabricated in an LC2MOS process. The AD7828 specifically offers eight multiplexed analog inputs, whereas the AD7824 provides four. Both share the same half-flash conversion architecture and interface timing.

Replacement Considerations

The AD7828LN is a direct functional replacement within the same package offering tighter error specifications. For industrial temperature ranges, the AD7828CQ or AD7828BR are available alternatives. Verify pin compatibility when substituting with other 28-lead packages.