Part A
AD7894ARZ-3
テキサス・インスツルメンツ
- Lifecycle
- Active
- Stock
- 3263 個数
- Package
- SOIC-8
- 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 AD7894ARZ-3 and AD7893BR-2 are both 12-bit successive-approximation ADCs from Analog Devices in an 8-lead SOIC package, sharing a similar serial interface architecture, but they differ in input channel configuration, throughput rate, and specified accuracy grade. The AD7894ARZ-3 offers a single input channel with a 5 µs conversion time, while the AD7893BR-2 provides a faster 1.6 µs conversion time with a higher grade linearity specification. Designers should validate the input configuration, timing, and accuracy requirements against the target application before substituting one for the other.
Input Channel Configuration
Validation required
Throughput Rate
Validation required
Package Type
High match
Accuracy Grade
Validation required
Parts at a glance
Part B
AD7893BR-2
テキサス・インスツルメンツ
- Lifecycle
- Active
- Stock
- 5300 個数
- Package
- SOIC-8
- 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 | AD7894ARZ-3 | AD7893BR-2 | Why it matters |
|---|---|---|---|
| Resolution | 14 bit | 12 bit | Higher resolution provides finer quantization steps, directly affecting measurement accuracy and dynamic range. |
| Number of Input Channels | 1 (single-ended) | 1 (single-ended) | Both are single-channel devices, so channel count is not a differentiator for substitutability. |
| Sampling Rate | 200 kSPS | 117 kSPS | Maximum throughput determines the highest signal frequency that can be digitized without aliasing. |
| Input Voltage Range | 0 V to +2.5 V (unipolar) | 0 V to +2.5 V (unipolar) | The analog input span must match the sensor or signal source to avoid clipping or loss of resolution. |
| Supply Voltage | 5 V single supply | 5 V single supply | Supply compatibility ensures the part can drop into the same power rail without redesign. |
| Interface Type | Serial (SPI/QSPI compatible) | Serial (SPI/QSPI compatible) | Matching serial interface allows reuse of the same digital host port and firmware. |
| Package / Mounting | 20-lead SOIC (surface mount) | 8-lead SOIC (surface mount) | Different package footprints require PCB layout changes, affecting direct board-level substitution. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Industrial temperature range confirms suitability for the same environmental conditions. |
| Power Consumption | Typically 20 mW | Typically 25 mW | Power draw affects thermal budget and supply sizing in low-power or portable designs. |
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 | AD7894ARZ-3 | AD7893BR-2 |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| Number of Bits | 14 | 12 |
| Sampling Rate(Per Second) | 200k | 117k |
| Number of Inputs | 1 | 1 |
| Input Type | Single Ended | Single Ended |
| Data Interface | SPI | SPI |
| 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 | External |
| Voltage - Supply, Analog | 5V | 5V |
| Voltage - Supply, Digital | 5V | 5V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
Frequently asked questions
What are the key differences between the AD7894ARZ-3 and AD7893BR-2?
The AD7894ARZ-3 is a 14-bit successive-approximation ADC with a 3 V supply range and a 5 µs conversion time, housed in a 24-lead SOIC package. The AD7893BR-2 is a 12-bit successive-approximation ADC with a 2.5 V reference and a 6 µs conversion time, housed in an 8-lead SOIC package. The AD7894ARZ-3 offers higher resolution (14-bit vs 12-bit) and a faster conversion time, while the AD7893BR-2 provides a smaller package footprint.
Are the AD7894ARZ-3 and AD7893BR-2 pin-compatible?
No. The AD7894ARZ-3 is supplied in a 24-lead SOIC package, while the AD7893BR-2 is supplied in an 8-lead SOIC package. The two devices have different pin counts and pin functions, so they are not pin-compatible and cannot be interchanged on the same PCB land pattern without redesign.
What are the resolution and conversion time specifications for each device?
The AD7894ARZ-3 provides 14-bit resolution with a conversion time of 5 µs. The AD7893BR-2 provides 12-bit resolution with a conversion time of 6 µs. The AD7894ARZ-3 therefore delivers two additional bits of resolution and a slightly faster conversion.
What supply voltage and reference requirements apply to each part?
The AD7894ARZ-3 operates from a 3 V supply (specifically the -3 grade, nominally 3.3 V range) and uses an external reference. The AD7893BR-2 operates from a 5 V supply and includes an on-chip 2.5 V reference. Designers must account for these differences in supply rail and reference architecture when comparing the two devices.
What are the package and temperature grade differences between the AD7894ARZ-3 and AD7893BR-2?
The AD7894ARZ-3 is offered in a 24-lead SOIC package in the A grade (commercial temperature range). The AD7893BR-2 is offered in an 8-lead SOIC package in the B grade (industrial temperature range). The B grade typically denotes tighter specifications than the A grade, and the industrial temperature range differs from the commercial range.
Can the AD7893BR-2 be used as a drop-in replacement for the AD7894ARZ-3?
No. The two devices differ in resolution (12-bit vs 14-bit), package (8-lead SOIC vs 24-lead SOIC), supply voltage (5 V vs 3 V), reference architecture (internal 2.5 V vs external), and conversion time (6 µs vs 5 µs). A direct drop-in replacement is not possible; any substitution requires a full design review against the manufacturer datasheets.
Which device is better suited for low-power or space-constrained designs?
The AD7893BR-2 is better suited for space-constrained designs because it is housed in an 8-lead SOIC package, compared with the 24-lead SOIC package of the AD7894ARZ-3. For supply voltage considerations, the AD7894ARZ-3 operates from a 3 V supply, which may be advantageous in low-voltage systems, whereas the AD7893BR-2 requires a 5 V supply.