Part A
AD7685ARMZRL7
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 1265 Stückzahl
- Package
- MSOP-10
- Series
- Datenerfassung mit Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The AD7685ARMZRL7 and AD7683ARM are both 16-bit, single-channel, pseudo-differential successive-approximation ADCs from Analog Devices in the same 10-lead MSOP package, sharing a compatible serial interface and reference architecture. The AD7685ARMZRL7 offers a higher throughput rate of 250 kSPS versus 100 kSPS for the AD7683ARM, so the AD7683ARM can serve as a functional substitute in applications where the lower sample rate is acceptable, while the faster AD7685ARMZRL7 can replace the AD7683ARM where additional bandwidth headroom is beneficial. Designers should validate timing margins and throughput requirements before committing to the swap.
Resolution and Architecture
High match
Package and Pinout
High match
Digital Interface
High match
Sampling Rate
Validation required
Parts at a glance
Part B
AD7683ARM
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 3371 Stückzahl
- Package
- TSSOP-8
- Series
- Datenerfassung mit Analog to Digital Converters (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 | AD7685ARMZRL7 | AD7683ARM | 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 if the application requires faster sampling. |
| Number of Input Channels | 1 (single-ended) | 1 (single-ended) | Both are single-channel devices, so channel count is compatible for direct substitution. |
| Input Type | Single-ended | Single-ended | Matching input configuration ensures the same signal conditioning can be reused. |
| Interface | SPI / DSP serial (CS, SCLK, SDO) | SPI / DSP serial (CS, SCLK, SDO) | Identical serial interface simplifies firmware and board-level compatibility. |
| Supply Voltage (VDD) | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Same supply range allows operation from the same power rail without redesign. |
| Package | 10-lead MSOP | 8-lead MSOP | Different pin counts and footprints mean the PCB layout must be adapted; they are not drop-in replacements. |
| 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) | 3.5 mW at 5 V, 250 kSPS | 4.5 mW at 5 V, 100 kSPS | Power budget differences affect thermal and energy-sensitive designs. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD7685ARMZRL7 | AD7683ARM |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Series | PulSAR® | PulSAR® |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 250k | 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 | 2.3V ~ 5.5V | - |
| Voltage - Supply, Digital | 2.3V ~ 5.5V | - |
Frequently asked questions
What are the key differences between the AD7685ARMZRL7 and the AD7683ARM?
The AD7685ARMZRL7 is a 16-bit, 250 kSPS PulSAR analog-to-digital converter, while the AD7683ARM is a 16-bit, 100 kSPS PulSAR ADC. Both are offered in a 10-lead MSOP package and operate from a single 2.7 V to 5.5 V supply, but they differ in throughput rate and in their digital interface and reference architecture.
Are the AD7685ARMZRL7 and AD7683ARM 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, because the digital interface and reference connections differ between the two parts.
What is the maximum throughput of each device?
The AD7685ARMZRL7 supports a maximum throughput of 250 kSPS. The AD7683ARM supports a maximum throughput of 100 kSPS.
What digital interface does each ADC use?
The AD7685ARMZRL7 uses an SPI-compatible serial interface with a separate SDI input, allowing it to be daisy-chained or read back on SDO. The AD7683ARM uses a 3-wire, SPI/QSPI/MICROWIRE/DSP-compatible serial interface without a separate SDI data input.
How is the reference supplied on each part?
The AD7685ARMZRL7 uses an external reference applied to the REF pin. The AD7683ARM also uses an external reference, but its reference input range and internal reference buffer configuration differ, so the reference voltage and decoupling must be verified against each datasheet.
What are the supply voltage and power consumption specifications?
Both devices operate from a single 2.7 V to 5.5 V supply. Power consumption scales with throughput and supply voltage; the AD7685ARMZRL7, operating at up to 250 kSPS, consumes more power at full rate than the AD7683ARM at its 100 kSPS maximum rate. Exact quiescent and operating currents should be taken from the respective datasheets.
Can the AD7683ARM be used as a drop-in replacement for the AD7685ARMZRL7 in an existing design?
Not without validation. Although both are 16-bit PulSAR ADCs in a 10-lead MSOP package, the differences in maximum throughput, serial interface (presence of SDI), and reference configuration mean the system timing, firmware, and analog front end must be re-verified against the AD7683ARM datasheet before substitution.
What are the typical applications for these ADCs?
Both parts are suited to battery-powered, multichannel data acquisition, medical instrumentation, and industrial process control where 16-bit resolution is required. The AD7685ARMZRL7 is preferred where higher throughput (up to 250 kSPS) is needed, while the AD7683ARM suits lower-rate, lower-power designs up to 100 kSPS.