Part A
AD7685BCPZRL7
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4541 Stückzahl
- Package
- LFCSP-10
- Series
- Datenerfassung mit Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The AD7683ACPZRL is a viable functional replacement candidate for the AD7685BCPZRL7 in many precision data-acquisition designs, as both are 16-bit pseudo-differential SAR ADCs sharing the same LFCSP-8 footprint and comparable serial interface. However, the AD7683 offers a lower throughput of 100 kSPS versus 250 kSPS and a narrower analog input range, so the substitution should be validated against the target sampling rate and signal swing requirements before adoption.
Resolution and Linearity
Validation required
Sampling Rate
Not compatible
Package and Pinout
High match
Analog Input Range
Validation required
Parts at a glance
Part B
AD7683ACPZRL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2812 Stückzahl
- Package
- VDFN-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 | AD7685BCPZRL7 | AD7683ACPZRL | Why it matters |
|---|---|---|---|
| Resolution (bits) | 16 | 16 | Both are 16-bit ADCs, so resolution is equivalent and not a differentiator for substitutability. |
| Sampling Rate (max) | 250 kSPS | 100 kSPS | The AD7685 supports a higher throughput, which matters if the application requires faster sampling than 100 kSPS. |
| Number of Input Channels | 1 (single-ended) | 1 (single-ended) | Both are single-channel devices, so channel count is not a differentiator. |
| Input Type | Single-ended, pseudo-differential | Single-ended, pseudo-differential | Matching input configuration supports similar signal-chain topologies. |
| Interface | SPI / QSPI / MICROWIRE / DSP compatible | SPI / QSPI / MICROWIRE / DSP compatible | Identical serial interface compatibility simplifies drop-in replacement at the digital interface level. |
| Supply Voltage (VDD) | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Same supply range means both can operate from common system rails without redesign. |
| Package | 10-Lead LFCSP (3 mm x 3 mm) | 8-Lead LFCSP (3 mm x 3 mm) | Different pin count and footprint require PCB layout changes, affecting direct board-level substitution. |
| Power Consumption (typical) | 3.5 mW at 5 V, 250 kSPS | 1.4 mW at 5 V, 100 kSPS | Lower power per conversion in the AD7683 may matter for battery-powered or thermally constrained designs. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Identical industrial temperature range supports use in the same environmental conditions. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD7685BCPZRL7 | AD7683ACPZRL |
|---|---|---|
| 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 | Pseudo-Differential |
| 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 | External |
| Voltage - Supply, Analog | 2.3V ~ 5.5V | 2.7V ~ 5.5V |
| Voltage - Supply, Digital | 2.3V ~ 5.5V | 2.7V ~ 5.5V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
Frequently asked questions
What are the key differences between the AD7685BCPZRL7 and AD7683ACPZRL?
The AD7685BCPZRL7 is a 16-bit, 250 kSPS PulSAR analog-to-digital converter, while the AD7683ACPZRL is a 16-bit, 100 kSPS PulSAR ADC. Both are single-channel, successive-approximation ADCs in 10-lead LFCSP packages, but they differ in throughput rate, power consumption, and serial interface timing characteristics.
Are the AD7685BCPZRL7 and AD7683ACPZRL pin-compatible?
Both devices are offered in a 10-lead LFCSP (CP-10) package with the same pin count, but designers must verify the pin function assignments against the respective manufacturer datasheets before considering any layout reuse, as the serial data interface and configuration pins may differ.
What is the maximum sampling rate of each device?
The AD7685BCPZRL7 supports a maximum throughput of 250 kSPS, whereas the AD7683ACPZRL supports a maximum throughput of 100 kSPS. The higher sampling rate of the AD7685 makes it suitable for faster signal acquisition applications.
Do both ADCs use the same serial interface?
Both devices provide a serial digital output compatible with SPI/QSPI/MICROWIRE/DSP interfaces. However, the AD7685 uses a CS- and SCLK-based serial interface with a dedicated SDI configuration input, while the AD7683 uses a simpler 3-wire interface. Timing parameters and readback behavior should be checked against each datasheet.
How do the power consumption figures compare?
The AD7685BCPZRL7 typically consumes approximately 4 mW at 5 V and 250 kSPS, while the AD7683ACPZRL typically consumes approximately 4 mW at 5 V and 100 kSPS. Actual power scales with throughput, so the lower-speed AD7683 may consume less in low-rate applications.
What is the analog input configuration of these ADCs?
Both the AD7685BCPZRL7 and AD7683ACPZRL feature a pseudo-differential analog input with a single-ended input range of 0 V to VREF. The reference voltage is applied externally, and the input structure supports direct connection to various signal sources without additional buffering in many applications.
Can the AD7683ACPZRL be used as a drop-in replacement for the AD7685BCPZRL7?
Not directly. Although both are 16-bit PulSAR ADCs in 10-lead LFCSP packages, the AD7683 has a lower maximum throughput (100 kSPS vs. 250 kSPS) and a different serial interface protocol. A drop-in replacement requires verifying pin functions, timing, and system-level performance against the target design requirements.
What are the operating temperature ranges for these components?
Both the AD7685BCPZRL7 and AD7683ACPZRL are specified for operation over the industrial temperature range of −40°C to +85°C, making them suitable for industrial and instrumentation applications.