Part A
ADS7809U
Texas Instruments
- Lifecycle
- Active
- Stock
- 6471 PCS
- Package
- SOIC-20
- Series
- Acquisição de dados - Analogo para Convertedores Digitais (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADS7805UE4 is a viable functional replacement candidate for the ADS7809U, sharing the same 16-bit SAR architecture, 5V supply, and SOIC-28 footprint, though the designer must validate the slower 10 µs conversion time and reduced 100 kSPS throughput against the target application's timing budget before committing to the substitution.
Resolution and Architecture
High match
Package and Pinout
High match
Sampling Rate
Validation required
Conversion Time
Validation required
Parts at a glance
Part B
ADS7805UE4
Texas Instruments
- Lifecycle
- Active
- Stock
- 9151 PCS
- Package
- SOIC-28
- Series
- Acquisição de dados - Analogo para Convertedores Digitais (ADC)
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADS7809U | ADS7805UE4 | Why it matters |
|---|---|---|---|
| Resolution | 16 bit | 16 bit | Both are 16-bit SAR ADCs, so resolution is identical and not a differentiator for substitutability. |
| Sampling Rate | 100 kSPS | 100 kSPS | Identical throughput means either part can meet the same acquisition timing requirements. |
| Input Type | Single-ended | Single-ended | Both accept single-ended analog inputs, so signal conditioning topology remains compatible. |
| Input Voltage Range | ±10 V | ±10 V | Matching full-scale input range allows the same front-end scaling and protection circuitry to be reused. |
| Supply Voltage | 5 V (analog and digital) | 5 V (analog and digital) | Same single 5 V supply simplifies power rail design and ensures pin-compatible operation. |
| Interface | Parallel (byte/word) | Parallel (byte/word) | Identical parallel interface allows the same microcontroller or DSP bus connection without firmware changes. |
| Package | 28-SOIC | 28-SOIC | Same package and footprint enables drop-in board replacement without layout changes. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Identical industrial temperature range means both parts suit the same environmental conditions. |
| Internal Reference | Yes (on-chip) | Yes (on-chip) | Both include an internal reference, so no external reference circuit is required for either part. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADS7809U | ADS7805UE4 |
|---|---|---|
| Supplier | - | Texas Instruments |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 100k | 100k |
| Number of Inputs | 1 | 1 |
| Input Type | Single Ended | Single Ended |
| Data Interface | SPI, DSP | Parallel |
| Configuration | S/H-ADC | S/H-ADC |
| Ratio - S / H: ADC | 1:1 | 1:1 |
| Number of A/D Converters | 1 | 1 |
| Architecture | SAR | SAR |
| Reference Type | External, Internal | External, Internal |
| Voltage - Supply, Analog | 5V | 5V |
| Voltage - Supply, Digital | 5V | 5V |
| Operating Temperature | -40°C ~ 85°C | -25°C ~ 85°C |
Frequently asked questions
What are the key differences between the ADS7809U and ADS7805UE4?
The ADS7809U is a 16-bit successive-approximation ADC, while the ADS7805UE4 is a 16-bit delta-sigma ADC. The ADS7809U offers a faster sampling rate (up to 100 kSPS) with a parallel interface, whereas the ADS7805UE4 provides higher resolution noise performance with a serial interface and lower throughput. They differ in architecture, interface type, and typical application suitability.
Are the ADS7809U and ADS7805UE4 pin-compatible?
No. The ADS7809U is supplied in a 28-pin SOIC package with a parallel data interface, while the ADS7805UE4 is supplied in a 28-pin SOIC package but uses a serial interface. Pin functions and assignments differ, so they are not drop-in replacements for each other.
What is the sampling rate of each device?
The ADS7809U supports a maximum sampling rate of 100 kSPS. The ADS7805UE4 supports a maximum sampling rate of 20 kSPS. The ADS7809U is therefore better suited for higher-speed acquisition, while the ADS7805UE4 targets lower-speed, higher-accuracy applications.
What interface types do the ADS7809U and ADS7805UE4 use?
The ADS7809U provides a parallel 16-bit data output interface. The ADS7805UE4 provides a serial data output interface. System designers must account for this difference in microcontroller or FPGA interfacing when comparing the two parts.
Do both parts operate from the same supply voltage?
Yes. Both the ADS7809U and ADS7805UE4 operate from a single +5 V analog supply. This common supply requirement simplifies power rail design when evaluating either device, though external reference and digital interface considerations still differ.
Which part is better for low-noise, high-accuracy measurements?
The ADS7805UE4, based on delta-sigma architecture, typically delivers lower noise and higher effective resolution for DC and low-frequency signals. The ADS7809U, a SAR converter, is preferable when faster sampling is required. Selection should be based on the signal bandwidth and accuracy requirements of the application.
Can the ADS7809U directly replace the ADS7805UE4 in an existing design?
No. Because the two devices differ in conversion architecture, data interface (parallel versus serial), and timing characteristics, a direct substitution is not possible without redesigning the digital interface and validating the analog front end against the respective datasheets.