Part A
AD7655ASTZRL
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 1730 PCS
- Package
- LQFP-48
- Series
- Data Acquisition - Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The AD7655ASTZRL and AD7652AST share the same 16-bit SAR ADC architecture, 48-lead LQFP package, and parallel interface, making the AD7652AST a viable functional substitute for the AD7655ASTZRL in applications where dual simultaneous sampling is not required. Designers should validate the reduced channel count and the absence of simultaneous-sampling capability against their system requirements before committing to the replacement.
Resolution and Architecture
High match
Package Type
High match
Channel Count
Validation required
Simultaneous Sampling
Not compatible
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD7655ASTZRL | AD7652AST | Why it matters |
|---|---|---|---|
| Number of ADC Channels | 2 (simultaneous sampling) | 1 | Determines how many analog signals can be digitized; the AD7655 supports two simultaneous channels while the AD7652 supports only one, affecting multi-signal acquisition designs. |
| Resolution | 16 bits | 16 bits | Both provide 16-bit resolution, so precision and dynamic range are equivalent for signal conversion. |
| Sampling Rate | 500 kSPS | 500 kSPS | Identical throughput means both can handle the same maximum input signal bandwidth for Nyquist sampling. |
| Input Configuration | Pseudo-differential, 2 channels | Pseudo-differential, 1 channel | Defines the analog front-end topology; the AD7655 can accept two pseudo-differential inputs while the AD7652 accepts one, impacting channel count and board layout. |
| Interface Type | Parallel and Serial (SPI/QSPI/MICROWIRE/DSP) | Parallel and Serial (SPI/QSPI/MICROWIRE/DSP) | Both offer flexible digital interfaces, so host connectivity options are equivalent. |
| Supply Voltage (Analog) | 5 V | 5 V | Same analog supply simplifies power design and ensures comparable input range and performance. |
| Package / Mounting | 48-LQFP (surface mount) | 48-LQFP (surface mount) | Identical package and footprint allow drop-in PCB compatibility without layout changes. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Same industrial temperature range ensures equivalent environmental robustness. |
| Power Consumption | ~120 mW typical | ~100 mW typical | Lower power in the AD7652 may benefit thermally constrained designs, though both are similar in class. |
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 | AD7655ASTZRL | AD7652AST |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Series | PulSAR® | PulSAR® |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 1M | 500k |
| Number of A/D Converters | 1 | 1 |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Number of Inputs | 2, 4 | - |
| Input Type | Pseudo-Differential, Single Ended | - |
| Data Interface | SPI, Parallel, DSP | - |
| Configuration | MUX-S/H-MUX-ADC | - |
| Ratio - S / H: ADC | 2:1 | - |
| Architecture | SAR | - |
| Reference Type | External | - |
| Voltage - Supply, Analog | 5V | - |
| Voltage - Supply, Digital | 5V | - |
| Features | Simultaneous Sampling | - |
Frequently asked questions
What are the key architectural differences between the AD7655ASTZRL and the AD7652AST?
The AD7655ASTZRL is a dual-channel, 16-bit, 1 MSPS successive-approximation ADC with two simultaneous-sampling SAR cores, while the AD7652AST is a single-channel, 16-bit, 500 kSPS SAR ADC. The AD7655 provides two independent ADC channels in a single package, whereas the AD7652 provides one channel.
Are the AD7655ASTZRL and AD7652AST pin-compatible?
No. The AD7655ASTZRL is offered in a 48-lead LQFP package, and the AD7652AST is offered in a 48-lead LQFP package, but the pin functions differ because the AD7655 supports dual simultaneous-sampling channels while the AD7652 is single-channel. Pin assignments and control interfaces are not interchangeable, so the PCB layout must be designed for the specific part.
How do the throughput rates of the AD7655ASTZRL and AD7652AST compare?
The AD7655ASTZRL operates at up to 1 MSPS per channel, while the AD7652AST operates at up to 500 kSPS. The AD7655 therefore offers twice the per-channel throughput of the AD7652, in addition to providing two channels.
Do both parts support the same analog input voltage range?
Both devices support a 0 V to 2.5 V unipolar input range and a ±2.5 V bipolar input range, configurable via the input range selection. This common input range flexibility allows similar analog front-end designs, though the channel count and throughput differ.
What digital interfaces do the AD7655ASTZRL and AD7652AST provide?
Both devices provide a parallel interface and a serial interface (SPI/QSPI/MICROWIRE/DSP-compatible) for connection to host processors. The AD7655 includes two separate conversion result registers for its two channels, while the AD7652 provides a single result register for its single channel.
Can the AD7652AST be used as a drop-in replacement for the AD7655ASTZRL in an existing design?
No. Because the AD7655ASTZRL is a dual-channel device and the AD7652AST is single-channel, and because their pin functions and package pinouts differ, the AD7652 cannot be used as a drop-in replacement. A redesign of the analog front end, channel multiplexing, and PCB layout would be required.
What are the typical power consumption figures for these two ADCs?
The AD7655ASTZRL typically consumes approximately 120 mW at 1 MSPS with a 5 V supply, while the AD7652AST typically consumes approximately 65 mW at 500 kSPS with a 5 V supply. Actual power depends on supply voltage, throughput, and operating mode.
In what applications would the AD7655ASTZRL be preferred over the AD7652AST?
The AD7655ASTZRL is preferred when two channels must be sampled simultaneously, such as in motor control, power monitoring, or multi-axis sensor systems requiring phase-coherent sampling. The AD7652AST is suited to single-channel applications where 500 kSPS is sufficient and lower power or cost is desired.