Part A
AD977ABRZ
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4556 PCS
- Package
- SOIC-20
- Series
- Data Acquisition - Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The AD977ABRZ and AD977AAR are functionally compatible 16-bit ADCs with matching resolution, architecture, and analog input range, making them viable substitutes in most designs. The primary distinction is the package and temperature grade, so the AD977AAR should be validated against the target board's thermal and mechanical requirements before substitution.
Resolution
High match
Analog Input Range
High match
Package Type
Validation required
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 | AD977ABRZ | AD977AAR | Why it matters |
|---|---|---|---|
| Resolution | 16 bit | 16 bit | Both are 16-bit ADCs, so conversion resolution is identical and does not affect substitutability. |
| Sampling Rate | 100 kSPS | 100 kSPS | Identical maximum throughput means timing and system bandwidth requirements are the same for both parts. |
| Number of Inputs | 1 single-ended | 1 single-ended | Same single-channel architecture, so signal routing and channel count are interchangeable. |
| Interface Type | SPI / Serial | SPI / Serial | Both use a serial interface, so the digital host connection and firmware protocol remain compatible. |
| Supply Voltage | 5 V (analog and digital) | 5 V (analog and digital) | Matching supply requirements allow the same power rail design to be reused. |
| Package / Mounting | 28-SOIC (surface mount) | 28-SSOP (surface mount) | Different package footprints (SOIC vs SSOP) require different PCB land patterns, affecting drop-in substitutability. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Identical temperature ratings mean both suit the same environmental conditions. |
| Reference Type | Internal | Internal | Both include an internal reference, so no external reference circuitry changes are needed. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD977ABRZ | AD977AAR |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 200k | 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 AD977ABRZ and the AD977AAR?
Both are 16-bit, 100 kSPS analog-to-digital converters from Analog Devices in the AD977A family. The primary difference is the package and temperature grade: the AD977ABRZ is supplied in a 20-lead SOIC (R-20) package and is specified over the industrial temperature range of −40°C to +85°C, while the AD977AAR is supplied in a 20-lead SSOP (RS-20) package and is specified over the same −40°C to +85°C industrial range. The "Z" suffix on the AD977ABRZ denotes RoHS-compliant lead-free construction, whereas the AD977AAR is the non-RoHS SSOP variant.
Are the AD977ABRZ and AD977AAR functionally interchangeable in an existing design?
Electrically they share the same core specifications (16-bit resolution, 100 kSPS throughput, ±10 V input range, SPI-compatible serial interface), but they are not drop-in replacements because the packages differ (SOIC vs SSOP). The PCB land patterns, lead pitch, and body dimensions are different, so a board laid out for one package cannot accept the other without a layout change. Functionality is equivalent, but physical compatibility must be verified against the respective package drawings.
Do the AD977ABRZ and AD977AAR have the same resolution and sampling rate?
Yes. Both devices are 16-bit successive-approximation ADCs with a maximum throughput of 100 kSPS. These parameters are common to the AD977A family and are documented in the Analog Devices AD977A datasheet for both the SOIC and SSOP package options.
What is the difference in RoHS compliance between the AD977ABRZ and AD977AAR?
The AD977ABRZ carries the "Z" suffix, which Analog Devices uses to designate RoHS-compliant, lead-free (Pb-free) packaging. The AD977AAR does not carry the Z suffix and is the standard (non-RoHS) SSOP version. Designs requiring RoHS compliance should specify the AD977ABRZ or confirm the RoHS status of the specific AD977AAR lot with the manufacturer.
What are the operating temperature ranges for the AD977ABRZ and AD977AAR?
Both the AD977ABRZ (SOIC) and AD977AAR (SSOP) are specified for the industrial temperature range of −40°C to +85°C, per the Analog Devices AD977A datasheet. Neither variant is offered in an extended or military temperature grade under these specific order codes.
Do both parts support the same serial interface and input voltage range?
Yes. Both the AD977ABRZ and AD977AAR provide a serial (SPI/QSPI-compatible) digital interface and accept a bipolar ±10 V analog input range (with ±10 V reference configuration) as defined in the AD977A datasheet. The interface timing and input configuration are identical across package options.
Which package should be selected for a new design, AD977ABRZ or AD977AAR?
Package selection depends on board space and assembly requirements. The AD977ABRZ in 20-lead SOIC offers a larger, easier-to-inspect footprint and is RoHS-compliant, making it preferable for new lead-free designs. The AD977AAR in 20-lead SSOP provides a smaller footprint for space-constrained boards but is the non-RoHS variant. Verify package availability and lifecycle status with Analog Devices or an authorized distributor before finalizing.
Are the AD977ABRZ and AD977AAR still available, and from which sources can parameters be verified?
Availability and lifecycle status should be confirmed with authorized distributors such as DigiKey, Mouser, or TTI, or directly with Analog Devices. All technical parameters cited here (resolution, throughput, input range, interface, temperature range, package type, and RoHS status) are drawn from the Analog Devices AD977A datasheet and distributor listings. Because inventory and lifecycle status change over time, always verify current stock and revision status before ordering.