Part A
ADS1281IPW
STマイクロエレクトロニクス
- Lifecycle
- Active
- Stock
- 4383 個数
- Package
- TSSOP-24
- Series
- データ取得 - アナログ/デジタルコンバータ (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADS1281IPW and ADS1271IPWRG4 are both 24-bit delta-sigma ADCs in a TSSOP-24 package, but they differ in resolution architecture, data rate, and interface configuration. The ADS1281IPW offers higher resolution and lower noise for seismic and precision applications, while the ADS1271IPWRG4 provides higher throughput and a wider digital supply range. Designers should validate clocking, reference, and interface timing before substituting one for the other in an existing design.
Resolution and Architecture
Validation required
Data Rate
Validation required
Package Type
High match
Digital Interface
Validation required
Parts at a glance
Part B
ADS1271IPWRG4
STマイクロエレクトロニクス
- Lifecycle
- Active
- Stock
- 3837 個数
- Package
- TSSOP-16
- Series
- データ取得 - アナログ/デジタルコンバータ (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 | ADS1281IPW | ADS1271IPWRG4 | Why it matters |
|---|---|---|---|
| Resolution (bits) | 31 | 24 | Higher resolution enables finer signal detail and lower quantization noise, which is critical for precision measurement applications. |
| Maximum Sample Rate (SPS) | 4000 | 105000 | Sample rate determines the bandwidth of signals the ADC can capture; a much faster rate supports wider-bandwidth or multiplexed acquisition. |
| Architecture | Delta-Sigma | Delta-Sigma | Both use delta-sigma modulation, but their differing order and design affect noise shaping and achievable dynamic range. |
| Input Type | Differential | Differential | Differential inputs reject common-mode noise and improve accuracy in electrically noisy environments. |
| Supply Voltage (V) | 3.0 to 5.0 (analog), 1.8 to 3.3 (digital) | 4.75 to 5.25 (analog), 1.65 to 3.6 (digital) | Supply requirements determine power-rail compatibility and whether the part can drop into an existing board design. |
| Interface | SPI | SPI | A shared SPI interface simplifies digital connection, but timing and register behavior may differ between devices. |
| Package | TSSOP-24 | TSSOP-16 | Package footprint and pin count affect PCB layout and whether a direct board-level substitution is possible. |
| Operating Temperature Range (°C) | -40 to 85 | -40 to 105 | The temperature range defines the environments in which the part can reliably operate without performance degradation. |
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Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADS1281IPW | ADS1271IPWRG4 |
|---|---|---|
| Supplier | - | Texas Instruments |
| Part Status | Active | Discontinued at Digi-Key |
| Number of Bits | 31 | 24 |
| Sampling Rate(Per Second) | 4k | 105k |
| Number of Inputs | 1 | 1 |
| Input Type | Differential, Single Ended | Differential |
| Data Interface | SPI | SPI |
| Configuration | ADC | ADC |
| Number of A/D Converters | 1 | 1 |
| Architecture | Sigma-Delta | Sigma-Delta |
| Reference Type | External | External |
| Voltage - Supply, Analog | 5V | 5V |
| Voltage - Supply, Digital | 1.65V ~ 3.6V | 1.65V ~ 3.6V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 105°C |
Frequently asked questions
What are the key architectural differences between the ADS1281IPW and ADS1271IPWRG4?
The ADS1281IPW is a single-channel, 31-bit delta-sigma ADC designed for high-resolution seismic and energy exploration applications, featuring a programmable gain amplifier and selectable digital filter options. The ADS1271IPWRG4 is a 24-bit, single-channel delta-sigma ADC with a fixed gain of 1 and a choice of three digital filter modes (High-Speed, High-Resolution, Low-Power). The ADS1281 offers higher resolution and integrated PGA, while the ADS1271 provides lower power consumption and simpler fixed-gain signal chain.
Are the ADS1281IPW and ADS1271IPWRG4 pin-compatible?
No. The ADS1281IPW is supplied in a 24-pin TSSOP (PW) package, while the ADS1271IPWRG4 is supplied in a 16-pin TSSOP (PW) package. The pin counts and pin functions differ, so they are not drop-in replacements and require different PCB layouts.
How do the power consumption specifications compare between the two devices?
The ADS1271IPWRG4 is specified for approximately 35 mW in High-Speed mode, 27 mW in High-Resolution mode, and 15 mW in Low-Power mode at a 3.3 V analog supply. The ADS1281IPW typically dissipates around 135 mW at a 5 V analog supply. The ADS1271 is therefore significantly lower power, making it better suited to portable or power-constrained systems.
What are the maximum output data rates for each ADC?
The ADS1281IPW supports output data rates from 250 SPS up to 4 kSPS depending on filter selection. The ADS1271IPWRG4 supports 105 kSPS in High-Speed mode, 52 kSPS in High-Resolution mode, and 10.5 kSPS in Low-Power mode. The ADS1271 offers much higher throughput, while the ADS1281 targets lower-speed, high-resolution measurements.
Do both devices support the same analog supply voltage range?
No. The ADS1281IPW operates from a 5 V analog supply (with a separate 3.3 V digital supply), while the ADS1271IPWRG4 operates from a 5 V analog supply as well but is also specified for 3.3 V analog operation in some modes. Designers should consult the respective datasheets for the exact recommended operating conditions and supply sequencing requirements.
Which device is more suitable for seismic or high-resolution sensor applications?
The ADS1281IPW is specifically designed for seismic and energy exploration applications, offering 31-bit resolution, an integrated PGA, and selectable digital filters optimized for low-frequency signal acquisition. The ADS1271IPWRG4, with 24-bit resolution and fixed gain, is more general-purpose and better suited to industrial measurement and audio-band data acquisition where higher sample rates and lower power are priorities.
What digital interface do the ADS1281IPW and ADS1271IPWRG4 use?
Both devices provide a serial peripheral interface (SPI-compatible) for data output and configuration. The ADS1281IPW supports a flexible serial interface with dedicated DRDY, SCLK, DIN, and DOUT pins, while the ADS1271IPWRG4 offers a similar serial interface with mode selection pins for filter configuration. Neither device includes an on-chip microcontroller or parallel interface.