Part A
AD977ARZ
ADI公司
- Lifecycle
- Active
- Stock
- 7094 件
- Package
- SOIC-20
- Series
- 資料獲取-模數轉換器（ADC）
Replacement verdict
Compatible functional replacement candidate
The AD977ACR is a functionally compatible replacement candidate for the AD977ARZ, sharing the same 16-bit resolution, 100 kSPS sampling rate, and 20-pin SOIC package. The primary distinction is the specified operating temperature range, which requires validation against the target application's thermal environment before substitution.
Resolution
High match
Sampling Rate
High match
Package Type
High match
Operating Temperature Range
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 | AD977ARZ | AD977ACR | Why it matters |
|---|---|---|---|
| Package / Case | 20-SOIC (0.295", 7.50mm Width) | 20-SOIC (0.295", 7.50mm Width) | Package footprint and thermal characteristics affect PCB layout and drop-in compatibility. |
| Operating Temperature Range | -40°C to +85°C | 0°C to +70°C | Industrial-grade temperature range (ARZ) versus commercial-grade (ACR) determines suitability for harsh environments. |
| Grade / Temperature Designator | Industrial (A grade, -40°C to +85°C) | Commercial (C grade, 0°C to +70°C) | The grade suffix indicates tested temperature range and reliability screening level. |
| Resolution | 16-bit | 16-bit | Bit depth determines the quantization step and achievable dynamic range of the ADC. |
| Sampling Rate | 100 kSPS | 100 kSPS | Maximum throughput must meet the signal bandwidth requirements of the application. |
| Input Type | Single-ended, unipolar | Single-ended, unipolar | Input configuration determines signal conditioning and reference requirements. |
| Supply Voltage | 5 V (analog and digital) | 5 V (analog and digital) | Supply voltage compatibility ensures the part works with existing power rails. |
| Interface | Parallel (byte/word) | Parallel (byte/word) | Digital interface type must match the host processor or FPGA bus. |
| Internal Reference | Yes (2.5 V) | Yes (2.5 V) | An internal reference simplifies design and reduces external component count. |
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 | AD977ARZ | AD977ACR |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 100k | 200k |
| Number of Inputs | 1 | 1 |
| Input Type | Single Ended | Single Ended |
| Data Interface | SPI | SPI |
| Configuration | ADC | ADC |
| 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 | -40°C ~ 85°C |
Frequently asked questions
What are the key differences between the AD977ARZ and AD977ACR?
Both are 16-bit, 100 kSPS bipolar input ADCs from Analog Devices in the same functional family. The primary difference is the package and temperature grade: the AD977ARZ is supplied in a 20-lead SOIC (R-20) package, while the AD977ACR is supplied in a 28-lead SSOP (RS-28) package. Both are specified over the commercial temperature range of 0°C to +70°C. The AD977ACR offers a separate analog and digital ground arrangement and additional pinout flexibility due to its higher pin count.
Are the AD977ARZ and AD977ACR pin-compatible?
No. The AD977ARZ uses a 20-lead SOIC package and the AD977ACR uses a 28-lead SSOP package, so they have different pin counts, pin assignments, and PCB land patterns. They are not drop-in replacements for each other and require different board layouts.
Do the AD977ARZ and AD977ACR have the same resolution and throughput?
Yes. Both devices are 16-bit successive-approximation ADCs with a maximum throughput of 100 kSPS, and both feature a bipolar input range of ±10 V (with ±3.3 V and ±5 V ranges also available depending on configuration). The core conversion performance is equivalent between the two package variants.
What is the input voltage range for the AD977ARZ and AD977ACR?
Both devices support a bipolar analog input range of ±10 V, with additional selectable ranges of ±3.3 V and ±5 V. The input range is configured via the RANGE pin and the external reference, per the Analog Devices AD977 datasheet.
What interface do the AD977ARZ and AD977ACR provide?
Both parts provide a parallel 16-bit microprocessor-compatible interface with a conversion start input (CONVST) and a busy/status output. The AD977ACR, with its 28-lead package, exposes additional control and ground pins compared to the 20-lead AD977ARZ, but the digital data format and timing are equivalent.
Can the AD977ACR be used as a substitute for the AD977ARZ in an existing design?
Not directly. Because the two parts use different packages (28-lead SSOP vs. 20-lead SOIC) with different pinouts and footprints, a board redesign is required. Substitution is only possible after validating the pinout, ground scheme, and layout against the respective Analog Devices datasheets.
What are the operating temperature ranges for the AD977ARZ and AD977ACR?
Both the AD977ARZ and AD977ACR are specified over the commercial temperature range of 0°C to +70°C. Neither part is rated for the industrial or extended temperature range in these specific orderable variants.
What reference and supply requirements apply to the AD977ARZ and AD977ACR?
Both devices operate from a +5 V analog supply and a +5 V digital supply, and require an external reference (typically +2.5 V) for the internal reference buffer, per the AD977 datasheet. The AD977ACR's 28-lead package provides separate analog and digital ground pins, which can improve noise isolation in mixed-signal layouts.