Part A
AD7685CRMZRL7
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4976 PCS
- Package
- MSOP-10
- Series
- Data Acquisition - Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The AD7685CRMZRL7 and AD7680ARM are both 16-bit successive-approximation ADCs from Analog Devices, but they differ in resolution-critical architecture, sampling rate, and package. The AD7685CRMZRL7 offers a higher throughput of 250 kSPS in a 10-lead MSOP, while the AD7680ARM provides 100 kSPS in an 8-lead MSOP. Designers should validate timing, interface, and layout compatibility before substituting one for the other in a given application.
Resolution and Architecture
Validation required
Sampling Rate
Not compatible
Package Type
Validation required
Supply Voltage
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 | AD7685CRMZRL7 | AD7680ARM | Why it matters |
|---|---|---|---|
| Resolution (bits) | 16 | 16 | Both are 16-bit ADCs, so nominal resolution is equivalent for substitutability. |
| Sampling Rate (max) | 250 kSPS | 100 kSPS | The AD7685 supports a higher throughput, which matters for faster signal acquisition requirements. |
| Number of Input Channels | 1 (single-ended) | 1 (single-ended) | Both provide a single analog input channel, so channel count is not a differentiator. |
| Interface Type | SPI / QSPI / MICROWIRE / DSP compatible serial | SPI / QSPI / MICROWIRE / DSP compatible serial | Identical serial interface simplifies drop-in replacement in digital host systems. |
| Supply Voltage (VDD) | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Same supply range allows use in the same power rail designs. |
| Package / Mounting | 10-Lead MSOP (surface mount) | 8-Lead MSOP (surface mount) | Different pin counts and footprints mean the PCB layout must be redesigned for substitution. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Equivalent temperature ratings support use in the same environmental conditions. |
| Power Consumption (typical) | ~4 mW at 5 V, 250 kSPS | ~3.5 mW at 5 V, 100 kSPS | Lower power per conversion affects thermal and battery-life budgets in portable designs. |
| Reference Type | External reference | External reference | Both require an external reference, so reference circuitry can be reused. |
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 | AD7685CRMZRL7 | AD7680ARM |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Series | PulSAR® | PulSAR® |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 250k | 100k |
| Number of Inputs | 1 | 1 |
| Input Type | Pseudo-Differential | Single Ended |
| Data Interface | SPI, DSP | SPI, DSP |
| 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 | Supply |
| Voltage - Supply, Analog | 2.3V ~ 5.5V | 2.5V ~ 5.5V |
| Voltage - Supply, Digital | 2.3V ~ 5.5V | 2.5V ~ 5.5V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
Frequently asked questions
What are the key differences between the AD7685CRMZRL7 and the AD7680ARM?
The AD7685CRMZRL7 is a 16-bit, 250 kSPS PulSAR analog-to-digital converter in a 10-lead MSOP package, while the AD7680ARM is a 16-bit, 100 kSPS PulSAR ADC in an 8-lead MSOP package. The AD7685 offers a higher throughput rate and includes a separate VIO supply pin for flexible logic interfacing, whereas the AD7680 provides a lower sample rate in a smaller pin count package.
Are the AD7685CRMZRL7 and AD7680ARM pin-compatible?
No. The AD7685CRMZRL7 uses a 10-lead MSOP package and the AD7680ARM uses an 8-lead MSOP package, so the pin counts and PCB land patterns differ. They are not direct drop-in replacements for each other.
What is the maximum sampling rate of each device?
The AD7685CRMZRL7 supports a maximum throughput of 250 kSPS. The AD7680ARM supports a maximum throughput of 100 kSPS.
Do both parts use the same serial interface?
Both devices provide a serial digital output compatible with SPI/QSPI/MICROWIRE/DSP interface standards. However, the AD7685CRMZRL7 includes a separate VIO pin that allows the digital interface supply to be set independently, while the AD7680ARM does not provide a separate VIO pin.
What are the resolution and architecture of these ADCs?
Both the AD7685CRMZRL7 and the AD7680ARM are 16-bit successive-approximation register (SAR) analog-to-digital converters based on the Analog Devices PulSAR architecture.
Can the AD7680ARM be used as a replacement for the AD7685CRMZRL7 in an existing design?
Not without redesign. The AD7680ARM has a lower maximum throughput (100 kSPS vs 250 kSPS), a different package and pin count (8-lead vs 10-lead MSOP), and lacks the separate VIO supply pin of the AD7685CRMZRL7. The PCB layout and timing budget must be revalidated against the manufacturer datasheets before substitution.
What analog input configuration do these converters support?
Both the AD7685CRMZRL7 and the AD7680ARM are single-channel, pseudo-differential input ADCs that sample a single analog input against a reference. Designers should confirm the exact input voltage range and reference requirements in the respective Analog Devices datasheets.