ADS7808UB Equivalent & Substitute Parts

Part Overview

The ADS7808UB is a 12-bit Analog to Digital Converter (ADC) manufactured by Texas Instruments, configured as a single-channel SAR (Successive Approximation Register) architecture device in a 20-SOIC surface mount package. This component is designated as Last Time Buy, indicating end-of-life status. Finding equivalent or substitute parts is necessary to ensure design continuity and long-term product availability for new designs or production transitions.

Substiute Parts

ADS7808UB

Texas InstrumentsIn Stock: 1214ADS7808UB Datasheet

Current PartRFQ

ADS8665IPWR

Texas InstrumentsIn Stock: 15306ADS8665IPWR Datasheet

MFR RecommendedRFQ

ADS8508IBDW

Texas InstrumentsIn Stock: 1484ADS8508IBDW Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the ADS7808UB is evaluated based on the following critical parameters that determine functional compatibility:

Core Compatibility Criteria:

• Resolution: 12-bit (must match)
• Architecture: SAR (must match)
• Number of Inputs: 1 (must match)
• Input Type: Single Ended (must match)
• Data Interface: SPI or DSP (must support at least SPI)
• Package Type: 20-SOIC preferred for direct PCB compatibility
• Supply Voltages: Analog 5V and Digital 5V (must be compatible)
• Operating Temperature Range: -40°C ~ 85°C (must meet or exceed)

Identified Substitutes:

1. ADS8665IPWR (MFR Recommended) - Manufacturer recommended substitute with enhanced specifications including higher sampling rate (500 kSPS), internal oscillator, and programmable gain amplifier (PGA). Package differs (16-TSSOP vs. 20-SOIC), requiring PCB layout modification. Supports differential and pseudo-differential inputs in addition to single-ended. Product Status: Active.

2. ADS8508IBDW (Direct Substitute) - Direct functional equivalent with identical package (20-SOIC), same supply voltages, and same operating temperature range. Sampling rate increased to 250 kSPS. Maintains single-ended input configuration and S/H:ADC ratio of 1:1. Product Status: Active with improved moisture sensitivity rating (MSL 2).

Parameter Comparison

Engineering Selection Recommendations

For Direct PCB Replacement (No Layout Changes): Select ADS8508IBDW. This part maintains identical package geometry (20-SOIC), identical supply voltage requirements (5V analog and digital), and identical operating temperature range (-40°C ~ 85°C). The increased sampling rate (250 kSPS vs. 100 kSPS) provides performance headroom without design modification. Product Status is Active with improved moisture sensitivity rating (MSL 2 vs. MSL 3), enhancing long-term reliability. All compliance certifications (ROHS3, REACH Unaffected, EAR99) are maintained.

For Enhanced Performance with Layout Redesign: Select ADS8665IPWR when design flexibility permits PCB modification. This manufacturer-recommended substitute offers significantly higher sampling rate (500 kSPS), extended operating temperature range (-40°C ~ 125°C), integrated programmable gain amplifier (PGA), and internal oscillator. The 16-TSSOP package requires PCB redesign but occupies less board space. Digital supply voltage flexibility (1.65V ~ 5.25V) enables integration with lower-voltage logic systems. Product Status is Active with full compliance certifications maintained.

Frequently Asked Questions (FAQ)

Q: Can ADS8665IPWR be used as a direct drop-in replacement for ADS7808UB? A: No. While functionally equivalent in resolution, sampling architecture, and core specifications, the ADS8665IPWR uses a 16-TSSOP package versus the 20-SOIC package of the ADS7808UB. PCB layout and footprint redesign is required. Additionally, the ADS8665IPWR supports differential and pseudo-differential inputs, whereas the ADS7808UB is single-ended only.

Q: Is ADS8508IBDW a direct drop-in replacement? A: Yes. The ADS8508IBDW maintains the identical 20-SOIC package footprint, supply voltage requirements (5V analog and digital), and operating temperature range (-40°C ~ 85°C) as the ADS7808UB. No PCB layout modifications are necessary. The increased sampling rate (250 kSPS) is backward compatible with designs expecting 100 kSPS operation.

Q: What is the primary difference between the two substitute options? A: ADS8508IBDW prioritizes form-factor compatibility and ease of integration with identical packaging and pinout. ADS8665IPWR prioritizes enhanced performance specifications including 5x higher sampling rate, extended temperature range, and integrated signal conditioning (PGA), at the cost of package redesign.

Q: Are both substitutes RoHS and REACH compliant? A: Yes. Both ADS8665IPWR and ADS8508IBDW are ROHS3 Compliant and REACH Unaffected, matching the compliance status of the ADS7808UB.

Q: How does the moisture sensitivity level affect component selection? A: ADS8508IBDW has an improved moisture sensitivity level (MSL 2, 1 Year) compared to both ADS7808UB and ADS8665IPWR (MSL 3, 168 Hours). This provides extended shelf life and reduced risk of moisture-induced failures during storage and assembly processes.

Q: Can the ADS7808UB operate with the digital supply voltage of ADS8665IPWR (1.65V ~ 5.25V)? A: No. The ADS7808UB requires a fixed 5V digital supply. The ADS8665IPWR's flexible digital supply range (1.65V ~ 5.25V) is a feature of that specific device and cannot be applied retroactively to the ADS7808UB.