Part A
AD7683BRMZ
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 5609 PCS
- Package
- MSOP-8
- Series
- Data Acquisition - Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The AD7683BRMZ and AD7684BRM are both 16-bit, 100 kSPS successive-approximation ADCs in 8-lead MSOP packages with a pseudo-differential input structure, making them strong functional replacement candidates. The AD7684BRM is a true differential input device, so the primary validation point is input configuration compatibility within the target signal chain. Designers should confirm input drive, reference, and layout requirements before substituting.
Resolution and Sample Rate
High match
Package Type
High match
Input Configuration
Validation required
Supply Voltage Range
High match
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD7683BRMZ | AD7684BRM | Why it matters |
|---|---|---|---|
| Resolution | 16 bits | 16 bits | Both are 16-bit SAR ADCs, so resolution is identical and not a differentiator for substitutability. |
| Number of Input Channels | 1 (single-ended) | 1 (differential) | Input configuration differs: the AD7683 accepts single-ended signals while the AD7684 accepts differential signals, affecting sensor interface design. |
| Input Type | Single-ended, pseudo-differential | Fully differential | Differential inputs offer better common-mode noise rejection; single-ended is simpler for ground-referenced signals. |
| Sampling Rate | 100 kSPS | 100 kSPS | Identical throughput, so timing and bandwidth requirements are interchangeable. |
| Supply Voltage | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Same supply range allows drop-in use in the same power rail design. |
| Interface | SPI / QSPI / MICROWIRE / DSP compatible | SPI / QSPI / MICROWIRE / DSP compatible | Identical serial interface simplifies firmware and host processor compatibility. |
| Package | 10-Lead MSOP | 10-Lead MSOP | Same package footprint enables PCB layout reuse without redesign. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Identical temperature range supports the same environmental conditions. |
| Power Consumption | 4 mW typical at 5 V, 100 kSPS | 4 mW typical at 5 V, 100 kSPS | Equivalent power draw means thermal and supply budgeting remain unchanged. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD7683BRMZ | AD7684BRM |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Series | PulSAR® | PulSAR® |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 100k | 100k |
| Data Interface | SPI, DSP | SPI, DSP |
| Number of A/D Converters | 1 | 1 |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Number of Inputs | 1 | - |
| Input Type | Pseudo-Differential | - |
| Configuration | S/H-ADC | - |
| Ratio - S / H: ADC | 1:1 | - |
| Architecture | SAR | - |
| Reference Type | External | - |
| Voltage - Supply, Analog | 2.7V ~ 5.5V | - |
| Voltage - Supply, Digital | 2.7V ~ 5.5V | - |
Frequently asked questions
What are the key differences between the AD7683BRMZ and the AD7684BRM?
The AD7683BRMZ is a 16-bit, 100 kSPS PulSAR analog-to-digital converter with a pseudo-differential input, while the AD7684BRM is a 16-bit, 100 kSPS PulSAR ADC with a true differential input. Both are offered in a 10-lead MSOP package and operate from a 2.7 V to 5.5 V single supply, but they differ in input configuration and therefore in the types of signals they can digitize.
Are the AD7683BRMZ and AD7684BRM pin-compatible?
Both devices are supplied in the same 10-lead MSOP (RM) package, but pin compatibility must be confirmed against the respective manufacturer pinouts before any substitution. The AD7683BRMZ uses a pseudo-differential input structure (IN+ and IN- with a defined common-mode range), whereas the AD7684BRM uses a true differential input, so the analog input pins are not functionally interchangeable even if the package footprint is identical.
What is the resolution and throughput of each device?
Both the AD7683BRMZ and the AD7684BRM are 16-bit successive-approximation (SAR) ADCs with a maximum throughput of 100 kSPS. Neither device includes an internal reference; both require an external reference voltage.
What input configuration does each ADC support?
The AD7683BRMZ provides a pseudo-differential input, where the IN- pin is limited to a small range near ground and the input span is defined by the external reference. The AD7684BRM provides a true differential input, allowing the IN+ and IN- pins to swing symmetrically about a common-mode voltage, which is advantageous for rejecting common-mode noise and for bipolar signal acquisition.
Do these ADCs have an internal voltage reference?
No. Both the AD7683BRMZ and the AD7684BRM are reference-less converters and require an external reference applied to the REF pin. The reference voltage sets the full-scale input range, and the reference must be stable and low-noise to achieve the specified 16-bit performance.
What supply voltage and interface do the AD7683BRMZ and AD7684BRM use?
Both devices operate from a single analog supply in the 2.7 V to 5.5 V range and provide a serial SPI-compatible interface for connection to a host processor or FPGA. The digital interface uses a separate VIO supply pin to allow logic-level compatibility with the host system.
In what applications would the AD7684BRM be preferred over the AD7683BRMZ?
The AD7684BRM is generally preferred when the signal source is differential or when common-mode rejection is important, such as in bridge sensor, instrumentation, and industrial measurement front ends. The AD7683BRMZ is suitable for single-ended or pseudo-differential signals referenced near ground, where a true differential input is not required.
Can the AD7683BRMZ and AD7684BRM be used interchangeably in an existing design?
They should not be treated as drop-in replacements without validation. Although both are 16-bit, 100 kSPS, 10-lead MSOP SAR ADCs, the pseudo-differential input of the AD7683BRMZ and the true differential input of the AD7684BRM impose different input drive, common-mode, and reference requirements. Any substitution must be verified against the manufacturer datasheets and the target design's signal chain.