ADS7824P Equivalent & Substitute Parts

Part Overview

The ADS7824P is a 12-bit Analog to Digital Converter (ADC) manufactured by Texas Instruments, designed for data acquisition applications requiring 4 single-ended inputs with a 40 kHz sampling rate. The device features a Successive Approximation Register (SAR) architecture with both SPI and parallel data interfaces, operating from a 5V supply across the -40°C to 85°C temperature range in a 28-DIP through-hole package.

The ADS7824P is classified as obsolete. Identifying equivalent and substitute parts is necessary to support legacy system maintenance, design updates, and procurement continuity when original inventory becomes unavailable.

Substiute Parts

ADS7824P

Texas InstrumentsIn Stock: 1278ADS7824P Datasheet

Current PartRFQ

ADS8634SRGER

Texas InstrumentsIn Stock: 1645ADS8634SRGER Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The ADS8634SRGER qualifies as a manufacturer-recommended substitute for the ADS7824P based on the following core substitution criteria:

Functional Equivalence:

• Both devices are 12-bit SAR ADCs with 4 single-ended inputs
• Both support external and internal reference configurations
• Both feature 1:1 Sample-and-Hold to ADC ratio
• Both contain a single A/D converter core

Electrical Compatibility:

• Both operate with 12-bit resolution and identical input channel count
• Both support SPI data interface (primary communication protocol)
• Both are RoHS3 compliant and REACH unaffected

Key Differences Requiring Design Consideration:

• Sampling rate: ADS8634SRGER operates at 1 MHz versus 40 kHz for ADS7824P
• Supply voltage range: ADS8634SRGER supports 2.7V to 5.25V (wider range) versus fixed 5V for ADS7824P
• Package: ADS8634SRGER uses 24-VQFN surface mount versus 28-DIP through-hole for ADS7824P
• Product status: ADS8634SRGER is active; ADS7824P is obsolete
• Operating temperature: ADS8634SRGER extends to 125°C versus 85°C for ADS7824P
• Additional feature: ADS8634SRGER includes integrated temperature sensor

Parameter Comparison

Engineering Selection Recommendations

The ADS8634SRGER is the manufacturer-recommended substitute for the obsolete ADS7824P. Selection of this substitute is supported by:

Product Status & Availability: The ADS8634SRGER maintains active product status with current manufacturing and distribution support, ensuring long-term availability and supply chain continuity compared to the obsolete ADS7824P.

Regulatory Compliance: Both devices maintain identical RoHS3 compliance and REACH unaffected status, satisfying regulatory requirements for equivalent component substitution in existing designs.

Functional Capability: The ADS8634SRGER exceeds the functional requirements of the ADS7824P across all critical parameters: 12-bit resolution, 4 single-ended inputs, SAR architecture, and dual reference support remain unchanged. The higher sampling rate (1 MHz versus 40 kHz) and extended temperature range (-40°C to 125°C) provide additional operational margin.

Design Integration Considerations: Substitution requires evaluation of two primary factors: (1) PCB layout modification due to package change from 28-DIP through-hole to 24-VQFN surface mount, and (2) firmware adaptation for SPI-only interface (parallel interface support is removed in the substitute). The wider supply voltage range of the ADS8634SRGER may simplify power supply design in applications with variable input voltages.

Frequently Asked Questions (FAQ)

Q: Can the ADS8634SRGER directly replace the ADS7824P without PCB modification?

A: No. The ADS7824P uses a 28-DIP through-hole package, while the ADS8634SRGER uses a 24-VQFN surface-mount package. PCB redesign is required. Additionally, the parallel interface of the ADS7824P is not available on the ADS8634SRGER; designs must use SPI communication exclusively.

Q: Are the 12-bit resolution and 4-input configurations identical between these devices?

A: Yes. Both devices provide 12-bit resolution with 4 single-ended inputs, SAR architecture, and support for external and internal reference configurations. These core specifications are equivalent.

Q: What is the impact of the higher sampling rate on system design?

A: The ADS8634SRGER operates at 1 MHz sampling rate compared to 40 kHz for the ADS7824P. This higher rate does not create incompatibility; it provides additional performance margin. Applications limited to 40 kHz operation will function correctly with the substitute. Firmware may require adjustment to manage the faster conversion rate if data buffering or timing-dependent logic is present.

Q: Does the extended temperature range of the ADS8634SRGER affect compatibility?

A: No. The ADS8634SRGER operating range (-40°C to 125°C) encompasses the ADS7824P range (-40°C to 85°C). Applications designed for the original temperature range will operate within the substitute's specifications.

Q: What supply voltage should be used with the ADS8634SRGER?

A: The ADS8634SRGER accepts analog supply voltage from 2.7V to 5.25V and digital supply voltage from 1.65V to 5.25V. For direct substitution in designs using 5V supplies, operation at 5V is fully supported. The wider voltage range allows flexibility in power supply design but does not require changes for existing 5V systems.

Q: Are both devices RoHS3 compliant?

A: Yes. Both the ADS7824P and ADS8634SRGER are RoHS3 compliant with identical MSL ratings (3, 168 hours), ensuring equivalent regulatory and environmental qualification status.