Part A
AD7654ASTZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2675 PCS
- Package
- LQFP-48
- Series
- Data Acquisition - Analog to Digital Converters (ADC)
Replacement verdict
Compatible functional replacement candidate
The AD7654ASTZ and AD7652ASTZRL are both 16-bit successive-approximation ADCs from Analog Devices in the same LQFP-48 package and share a high degree of functional overlap, making the AD7652ASTZRL a viable functional replacement candidate for the AD7654ASTZ in many designs. However, the AD7654ASTZ provides a dual simultaneous-sampling architecture with two independent ADC cores, whereas the AD7652ASTZRL is a single-channel device, so channel count and simultaneous-sampling capability must be validated against the target application before substitution.
Channel Count
Validation required
Resolution
High match
Package Type
High match
Sampling Architecture
Validation required
Parts at a glance
Part B
AD7652ASTZRL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 8882 PCS
- Package
- LQFP-48
- Series
- Data Acquisition - 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 | AD7654ASTZ | AD7652ASTZRL | Why it matters |
|---|---|---|---|
| Number of ADC Channels | 2 (simultaneous sampling) | 1 | Determines how many analog signals can be digitized; the AD7654 supports two simultaneous channels while the AD7652 supports only one, so they are not directly substitutable in multi-channel designs. |
| Sampling Rate | 500 kSPS | 500 kSPS | Both devices offer the same throughput, so timing and bandwidth requirements are matched between the two parts. |
| Resolution | 16 bits | 16 bits | Identical resolution means both provide the same quantization precision for the analog input signal. |
| Input Configuration | 2 single-ended / 2 pseudo-differential | 1 single-ended / 1 pseudo-differential | The input topology affects how many signals can be connected and whether differential measurements are possible; the AD7654 offers more input flexibility. |
| Interface Type | SPI / Parallel (selectable) | SPI / Parallel (selectable) | Both support the same serial and parallel host interfaces, so board-level digital connectivity is compatible. |
| Supply Voltage (Analog) | 5 V | 5 V | Matching analog supply requirements means the same power rail can be reused without redesign. |
| Package | 48-lead LQFP | 48-lead LQFP | Identical package and pin count allow the same PCB footprint, though pin functions may differ between the two parts. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Same industrial temperature range means both are suitable for the same environmental conditions. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD7654ASTZ | AD7652ASTZRL |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Series | PulSAR® | PulSAR® |
| Part Status | Active | Obsolete |
| Number of Bits | 16 | 16 |
| Sampling Rate(Per Second) | 500k | 500k |
| Number of Inputs | 2, 4 | 1 |
| Input Type | Pseudo-Differential, Single Ended | Pseudo-Differential |
| Data Interface | SPI, Parallel, DSP | SPI, Parallel, DSP |
| Configuration | MUX-S/H-MUX-ADC | S/H-ADC |
| Ratio - S / H: ADC | 2:1 | 1:1 |
| Number of A/D Converters | 1 | 1 |
| Architecture | SAR | SAR |
| Reference Type | External | External, Internal |
| Voltage - Supply, Analog | 5V | 5V |
| Voltage - Supply, Digital | 5V | 5V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Features | Simultaneous Sampling | - |
Frequently asked questions
What are the key differences between the AD7654ASTZ and the AD7652ASTZRL?
The AD7654ASTZ is a dual-channel, 16-bit, 500 kSPS successive-approximation ADC, while the AD7652ASTZRL is a single-channel, 16-bit, 500 kSPS PulSAR ADC. The AD7654 provides two simultaneous-sampling input channels in a 48-lead LQFP package, whereas the AD7652 offers one channel in a 48-lead LQFP package and is supplied in tape-and-reel form (the RL suffix). Both share the same 16-bit resolution and 500 kSPS throughput but differ in channel count and packaging format.
Are the AD7654ASTZ and AD7652ASTZRL pin-compatible?
No. Although both devices are housed in a 48-lead LQFP, their pinouts differ because the AD7654 is a dual-channel converter and the AD7652 is a single-channel converter. The analog input pins, channel-select and configuration pins, and several digital control pins are not identical, so the two parts cannot be treated as drop-in replacements without verifying the pin functions against the respective datasheets.
Do the AD7654ASTZ and AD7652ASTZRL have the same resolution and throughput?
Yes. Both are 16-bit successive-approximation ADCs with a maximum throughput of 500 kSPS. The AD7654 achieves this with two simultaneously sampled channels, while the AD7652 achieves it with a single channel. The core conversion architecture and resolution are equivalent, but the channel count and the resulting data interface behavior differ.
What is the significance of the "RL" suffix on the AD7652ASTZRL?
The "RL" suffix indicates tape-and-reel packaging, which is intended for automated pick-and-place assembly lines. The AD7654ASTZ is supplied in standard tray or tube packaging. The electrical performance of the AD7652ASTZRL is identical to the non-reel version of the AD7652; the suffix only denotes the shipping format.
Can the AD7654ASTZ be used as a replacement for the AD7652ASTZRL in an existing design?
Not directly. Because the AD7654ASTZ is a dual-channel device and the AD7652ASTZRL is a single-channel device, the pinout, channel configuration, and digital interface timing differ. A direct substitution would require PCB rework and firmware changes to accommodate the additional channel and the different control register behavior. The replacement should only be considered after validating all differences against the manufacturer datasheets.
What are the analog input configurations of the AD7654ASTZ and AD7652ASTZRL?
The AD7654ASTZ provides two independent analog input channels that can be configured for simultaneous sampling, supporting both unipolar and bipolar input ranges. The AD7652ASTZRL provides a single analog input channel with a similar unipolar/bipolar configuration capability. The input range and reference requirements should be confirmed from the respective datasheets for the specific operating mode.
Do both devices support the same digital interface?
Both devices provide a parallel digital interface for connection to a host processor or DSP, but the interface details are not identical because the AD7654 manages two channels while the AD7652 manages one. The data bus width, conversion-start and read timing, and channel-select signals differ. Designers must consult the timing specifications in each datasheet before reusing interface logic.
Are the AD7654ASTZ and AD7652ASTZRL available in the same package type?
Yes, both are offered in a 48-lead LQFP package. However, the AD7654ASTZ is a dual-channel part and the AD7652ASTZRL is a single-channel part, so the package outline is the same but the pin assignments are not interchangeable. The "ASTZ" designation in both part numbers refers to the LQFP package and the RoHS-compliant lead finish.