Part A
ADS1256IDBT
Texas Instruments
- Lifecycle
- Active
- Stock
- 4833 PCS
- Package
- SSOP-28
- Series
- Data Acquisition - Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADS1241E and ADS1256IDBT are both 24-bit delta-sigma ADCs from Texas Instruments, but they differ in resolution performance, channel count, and package footprint. The ADS1256IDBT offers higher resolution and more channels, making it a viable functional upgrade candidate for applications requiring greater precision and input flexibility, provided the board layout accommodates the different package and the system timing is revalidated.
Resolution
Validation required
Channel Count
Validation required
Package Type
Not compatible
Data Rate
Validation required
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADS1241E | ADS1256IDBT | Why it matters |
|---|---|---|---|
| Resolution (bits) | 24 | 24 | Both are 24-bit delta-sigma ADCs, so resolution alone does not distinguish them for substitutability. |
| Number of input channels | 8 (single-ended) / 4 (differential) | 8 (single-ended) / 4 (differential) | Channel count determines how many sensor inputs can be multiplexed without external circuitry. |
| Maximum sample rate (SPS) | 15 | 30000 | The ADS1256 supports far higher throughput, making it suitable for faster signals while the ADS1241E is limited to low-speed precision measurements. |
| Programmable gain amplifier (PGA) range | 1 to 128 | 1 to 64 | PGA range affects the smallest differential signal that can be resolved; the ADS1241E offers higher maximum gain for very small signals. |
| Interface | SPI (compatible) | SPI | Both use a serial peripheral interface, simplifying drop-in replacement at the digital communication level. |
| Supply voltage (analog) | 2.7 V to 5.25 V | 5 V (4.75 V to 5.25 V) | The ADS1241E operates over a wider low-voltage range, while the ADS1256 requires a nominal 5 V analog supply. |
| Package | SSOP-28 | TSSOP-28 | Different package footprints affect PCB layout and whether a direct board-level substitution is possible. |
| Operating temperature range | -40 °C to +85 °C | -40 °C to +85 °C | Identical temperature ratings mean both suit the same industrial environments. |
| Internal oscillator | No (external clock required) | No (external clock required) | Both require an external clock source, so clock circuitry must be provided in either design. |
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 | ADS1256IDBT | ADS1241E |
|---|---|---|
| Part Status | Active | Active |
| Number of Bits | 24 | 24 |
| Sampling Rate(Per Second) | 30k | 15 |
| Number of Inputs | 4, 8 | 8 |
| Input Type | Differential, Single Ended | Differential, Single Ended |
| Data Interface | SPI | SPI |
| Configuration | MUX-PGA-ADC | MUX-PGA-ADC |
| Number of A/D Converters | 1 | 1 |
| Architecture | Sigma-Delta | Sigma-Delta |
| Reference Type | External | External |
| Voltage - Supply, Analog | 5V | 2.7V ~ 3.3V, 5V |
| Voltage - Supply, Digital | 1.8V ~ 3.6V | 2.7V ~ 5.25V |
| Features | PGA | PGA |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
Frequently asked questions
What are the primary differences between the ADS1241E and ADS1256IDBT?
The ADS1241E is a 24-bit, 8-channel delta-sigma ADC with a maximum data rate of 15 SPS and a PGA gain range of 1 to 128, housed in a 28-pin TSSOP package. The ADS1256IDBT is a 24-bit, 8-channel (4 differential) delta-sigma ADC with a maximum data rate of 30 kSPS, a PGA gain range of 1 to 64, and is housed in a 28-pin TSSOP package. The ADS1256IDBT offers significantly higher throughput and includes a built-in input buffer, while the ADS1241E provides higher maximum PGA gain.
Are the ADS1241E and ADS1256IDBT pin-to-pin compatible?
No. Although both devices are offered in a 28-pin TSSOP package, their pin functions and internal architectures differ. The ADS1256IDBT includes additional features such as a input buffer and different digital interface timing, and the pin assignments are not identical. A direct PCB drop-in replacement is not supported without design verification against both datasheets.
Which device offers a higher maximum data output rate?
The ADS1256IDBT supports a maximum data rate of 30 kSPS, whereas the ADS1241E supports a maximum data rate of 15 SPS. The ADS1256IDBT is therefore better suited for applications requiring higher sampling throughput, while the ADS1241E targets low-speed, high-resolution measurement applications.
Do both ADCs support a programmable gain amplifier (PGA)?
Yes. Both the ADS1241E and ADS1256IDBT integrate a programmable gain amplifier. The ADS1241E supports PGA gains of 1, 2, 4, 8, 16, 32, 64, and 128. The ADS1256IDBT supports PGA gains of 1, 2, 4, 8, 16, 32, and 64. The ADS1241E provides a higher maximum gain setting of 128.
What are the supply voltage requirements for each device?
The ADS1241E operates from a single analog supply (AVDD) of 2.7 V to 5.25 V and a digital supply (DVDD) of 2.7 V to 5.25 V. The ADS1256IDBT operates from an analog supply (AVDD) of 5 V (4.75 V to 5.25 V) and a digital supply (DVDD) of 1.8 V to 3.6 V. The supply requirements differ, so power rail design must be verified for each part.
Which device is more suitable for high-resolution low-frequency sensor measurement?
The ADS1241E is optimized for low-speed, high-resolution measurements with data rates up to 15 SPS and PGA gain up to 128, making it suitable for precision sensor interfaces such as weigh scales and temperature sensing. The ADS1256IDBT offers higher speed (up to 30 kSPS) but a lower maximum PGA gain of 64. Selection depends on the required balance of resolution, gain, and throughput for the target application.
Do both devices support SPI-compatible serial communication?
Yes. Both the ADS1241E and ADS1256IDBT provide an SPI-compatible serial interface for communication with a host microcontroller. However, the command sets, register maps, and timing specifications differ between the two devices, so firmware must be developed or ported according to the respective datasheet.