Part A
ADS1210U
德州儀器
- Lifecycle
- Active
- Stock
- 5384 件
- Package
- SOIC-8
- Series
- 資料獲取-模數轉換器（ADC）
Replacement verdict
Not a drop-in replacement
The ADS1251U and ADS1210U are both 24-bit delta-sigma analog-to-digital converters, but they differ fundamentally in resolution architecture, interface type, package footprint, and reference configuration, so the ADS1251U cannot serve as a direct drop-in substitute for the ADS1210U without redesign of the surrounding circuitry and board layout.
Different interface type
Different package footprint
Different reference configuration
Different data rate capability
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADS1251U | ADS1210U | 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 | 1 (single-ended) | 1 (differential) | Input configuration affects whether the part can directly interface with a differential or single-ended sensor without external conditioning. |
| Maximum data rate (SPS) | 20k | 19.5k | Data rate determines the achievable sampling bandwidth and must meet the application's signal frequency requirements. |
| Interface type | Synchronous serial (SPI-compatible) | SPI-compatible serial | The digital interface must match the host microcontroller's available serial peripheral to allow direct connection. |
| Supply voltage (analog) | 5 V | 5 V | Analog supply voltage must be compatible with the system's power rails and the input signal range. |
| Package | SOIC-8 | SOIC-18 | Package footprint and pin count must match the PCB layout for a drop-in replacement. |
| PGA / gain stages | None (fixed gain) | Programmable gain amplifier (1–128) | An integrated PGA allows direct amplification of low-level signals, reducing external components and improving noise performance. |
| Internal reference | No (external reference required) | No (external reference required) | Both require an external reference, so reference design and accuracy considerations are similar for either part. |
| Operating temperature range | -40°C to +85°C | -40°C to +85°C | The temperature range must cover the application's environmental conditions for reliable operation. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADS1210U | ADS1251U |
|---|---|---|
| Part Status | Last Time Buy | Active |
| Number of Bits | 24 | 24 |
| Sampling Rate(Per Second) | 16k | 20k |
| Number of Inputs | 1 | 1 |
| Input Type | Differential | Differential |
| Data Interface | SPI | SPI |
| Configuration | PGA-ADC | ADC |
| Number of A/D Converters | 1 | 1 |
| Architecture | Sigma-Delta | Sigma-Delta |
| Reference Type | External, Internal | External |
| Voltage - Supply, Analog | 5V | 5V |
| Voltage - Supply, Digital | 5V | 5V |
| Features | PGA | - |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
Frequently asked questions
What are the key architectural differences between the ADS1251U and ADS1210U?
The ADS1251U is a 24-bit delta-sigma ADC with a fixed gain of 1 and a single differential input, offering data rates up to 20 kSPS. The ADS1210U is a 24-bit delta-sigma ADC featuring a programmable gain amplifier (PGA) with gains from 1 to 128, a flexible input multiplexer, and data rates up to 15.6 kSPS. The ADS1210U provides more configurability, while the ADS1251U offers a simpler, higher-speed single-channel solution.
Are the ADS1251U and ADS1210U pin-compatible?
No. Both devices are offered in a 24-pin SOIC package, but their pin functions differ. The ADS1210U includes additional pins for PGA control, multiplexer configuration, and external reference connections that are not present on the ADS1251U. Therefore, they are not drop-in replacements and require different PCB layouts.
How do the maximum data rates of the ADS1251U and ADS1210U compare?
The ADS1251U supports data rates up to 20 kSPS. The ADS1210U supports data rates up to 15.6 kSPS. The ADS1251U provides a higher maximum output rate, while the ADS1210U trades some speed for increased input flexibility and programmable gain.
Does the ADS1210U include a programmable gain amplifier while the ADS1251U does not?
Yes. The ADS1210U integrates a PGA with selectable gains of 1, 2, 4, 8, 16, 32, 64, and 128, allowing direct connection of low-level sensors. The ADS1251U has a fixed gain of 1 and does not include a PGA, so external amplification is required for small-signal inputs.
What are the reference voltage requirements for the ADS1251U and ADS1210U?
Both devices require an external reference voltage. The ADS1251U uses a differential reference input (VREFP and VREFN) with a specified reference range, while the ADS1210U also uses an external differential reference. Neither device includes an internal reference, so a stable external reference must be provided in both cases.
How do the power supply requirements of the ADS1251U and ADS1210U differ?
Both devices operate from a single 5 V analog supply (AVDD) and a 2.7 V to 5.25 V digital supply (DVDD). The ADS1251U typically consumes approximately 25 mW, while the ADS1210U consumes approximately 35 mW depending on configuration. Power consumption should be verified against the respective datasheets for the target operating conditions.
Which device is better suited for multi-channel applications?
The ADS1210U is better suited for multi-channel applications because it includes an input multiplexer that allows selection among multiple input channels. The ADS1251U has a single differential input and cannot multiplex between channels without external circuitry.
Can the ADS1251U and ADS1210U share the same SPI-compatible serial interface?
Both devices provide a serial interface for communication with a host controller, but the protocol details differ. The ADS1251U uses a simple read-only serial interface, while the ADS1210U supports a more flexible serial interface with additional command and configuration registers. Firmware must be adapted accordingly; the interfaces are not identical.