Part A
AD7490BRU
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2930 Stückzahl
- Package
- TSSOP-28
- Series
- Datenerfassung mit Analog to Digital Converters (ADC)
Replacement verdict
Not a drop-in replacement
The AD7490BRU and AD7492BRU-REEL are not drop-in replacements for each other. Although both are 12-bit successive-approximation ADCs from Analog Devices in a TSSOP package, they differ in channel count, digital interface, throughput, and analog input architecture, so a direct substitution would require board-level redesign and firmware changes.
Different channel count
Different digital interface
Different throughput rate
Different input architecture
Parts at a glance
Part B
AD7492BRU-REEL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 6865 Stückzahl
- Package
- TSSOP-24
- 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 | AD7490BRU | AD7492BRU-REEL | Why it matters |
|---|---|---|---|
| Number of ADC Channels | 16 | 1 | Determines how many analog signals can be sampled; a 16-channel multiplexed ADC cannot be directly substituted by a single-channel device without external multiplexing. |
| Resolution | 12 bits | 12 bits | Both provide 12-bit resolution, so quantization accuracy is equivalent, but channel count and architecture still differ. |
| Sampling Rate | 1 MSPS | 1.25 MSPS | Maximum throughput affects achievable signal bandwidth and timing margin in the system; the AD7492 offers a slightly higher conversion rate. |
| Input Type | Single-ended | Single-ended | Both accept single-ended inputs, so signal conditioning requirements are similar, though channel count differs significantly. |
| Supply Voltage | 2.7 V to 5.25 V | 2.7 V to 5.25 V | Compatible supply ranges allow both to operate from the same system rails, easing power design and level shifting. |
| Interface | SPI / QSPI / MICROWIRE / DSP compatible | SPI / QSPI / MICROWIRE / DSP compatible | Identical serial interface compatibility means the same host controller and firmware protocol can be reused. |
| Package | 24-lead TSSOP | 24-lead TSSOP | Same package footprint allows board-level drop-in compatibility without layout changes. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Identical industrial temperature ratings ensure both parts meet the same environmental requirements. |
| Power Consumption | Approx. 2.5 mW at 1 MSPS (5 V) | Approx. 3.5 mW at 1.25 MSPS (5 V) | Power budget differences affect thermal design and battery life in portable or dense systems. |
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 | AD7490BRU | AD7492BRU-REEL |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Obsolete | Obsolete |
| Number of Bits | 12 | 12 |
| Sampling Rate(Per Second) | 1M | 1M |
| Number of Inputs | 16 | 1 |
| Input Type | Single Ended | Single Ended |
| Data Interface | SPI, DSP | Parallel |
| Configuration | MUX-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 | Internal |
| Voltage - Supply, Analog | 2.7V ~ 5.25V | 2.7V ~ 5.25V |
| Voltage - Supply, Digital | 2.7V ~ 5.25V | 2.7V ~ 5.25V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
Frequently asked questions
What are the key architectural differences between the AD7490BRU and AD7492BRU-REEL?
The AD7490BRU is a 12-bit, 16-channel successive approximation ADC with a serial interface, housed in a 28-lead TSSOP. The AD7492BRU-REEL is a 12-bit, 4-channel successive approximation ADC with a parallel interface, supplied in a 24-lead TSSOP on tape and reel. The primary differences are channel count (16 vs 4), digital interface (serial vs parallel), and package pin count (28 vs 24).
Can the AD7490BRU and AD7492BRU-REEL be used interchangeably in the same PCB footprint?
No. The AD7490BRU uses a 28-lead TSSOP and the AD7492BRU-REEL uses a 24-lead TSSOP, so the package footprints and pin counts differ. In addition, the AD7490BRU provides a serial interface while the AD7492BRU-REEL provides a parallel interface, so the digital connections are not compatible. A direct drop-in replacement is not possible without a PCB redesign.
How do the sampling rates of the AD7490BRU and AD7492BRU-REEL compare?
Both devices are specified for a maximum throughput rate of 1 MSPS. The AD7490BRU achieves 1 MSPS with a 16 MHz serial clock, and the AD7492BRU-REEL achieves 1 MSPS with its parallel interface. Throughput is therefore comparable, but the interface bandwidth requirements differ.
What are the analog input configurations of the AD7490BRU and AD7492BRU-REEL?
The AD7490BRU provides 16 analog input channels that can be configured as single-ended inputs or as pairs in pseudo-differential mode, selected through its control register. The AD7492BRU-REEL provides 4 analog input channels with a similar single-ended or pseudo-differential configuration. The AD7490BRU offers more channels, while the AD7492BRU-REEL offers fewer channels with a parallel output bus.
Do the AD7490BRU and AD7492BRU-REEL operate from the same supply voltage?
Both devices operate from a single 2.7 V to 5.25 V supply. This allows either part to be used in 3 V or 5 V systems, subject to the timing and interface requirements of the selected device.
Which device is better suited for systems requiring many analog channels?
The AD7490BRU is better suited for high-channel-count systems because it provides 16 analog input channels in a single package. The AD7492BRU-REEL provides only 4 channels, so systems needing more than 4 inputs would require additional AD7492 devices or a different multiplexing scheme.
Which device is better suited for systems with a parallel microprocessor bus?
The AD7492BRU-REEL is better suited for systems with a parallel microprocessor bus because it provides a parallel digital interface. The AD7490BRU uses a serial interface, which is preferable when PCB routing must be minimized or when the host controller provides a serial port.
What is the significance of the -REEL suffix on the AD7492BRU-REEL?
The -REEL suffix indicates that the AD7492BRU devices are supplied on tape and reel for automated pick-and-place assembly. The AD7490BRU is typically supplied in tube or tray packaging unless a reel-specific ordering code is selected. The suffix affects packaging and handling, not the electrical specifications of the device.