Part A
AD7739BRUZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 1798 Stückzahl
- Package
- TSSOP-24
- Series
- Datenerfassung mit Analog to Digital Converters (ADC)
Replacement verdict
Not a drop-in replacement
The AD7739BRUZ and AD7730BRU-REEL are not drop-in replacements for one another. Although both are single-channel, 24-bit sigma-delta load-cell ADCs in 24-lead TSSOP packages, they differ in output data rate, analog input architecture, and interface timing, so a direct board-level swap is not supported without design validation.
Different output data rate
Different input architecture
Different interface timing
Different reference arrangement
Parts at a glance
Part B
AD7730BRU-REEL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2165 Stückzahl
- Package
- TSSOP-24
- Series
- Datenerfassung mit dem Analog Front End (AFE)
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD7739BRUZ | AD7730BRU-REEL | Why it matters |
|---|---|---|---|
| Resolution (bits) | 24 | 24 | Both are 24-bit sigma-delta ADCs, so resolution alone does not differentiate them for substitutability. |
| Number of input channels | 8 (differential, 4 differential pairs) | 2 (differential) | Channel count determines how many sensor signals can be measured; the AD7739 supports far more inputs than the AD7730. |
| Maximum throughput / output data rate | Up to 15.1 kSPS | Up to 800 SPS (200 Hz typical for weigh-scale use) | Higher output rates enable faster sampling; the AD7739 is significantly faster than the AD7730. |
| Interface type | SPI / serial (3-wire) | SPI / serial (3-wire) | Both use a serial interface, so host microcontroller compatibility is similar. |
| Supply voltage (analog) | 5 V (single supply, 4.75 V to 5.25 V) | 5 V (single supply, 4.75 V to 5.25 V) | Matching analog supply requirements simplifies power-rail design when substituting parts. |
| Package | 24-lead TSSOP | 24-lead TSSOP | Identical package footprint allows drop-in PCB compatibility without layout changes. |
| On-chip PGA / gain stages | Yes (programmable gain) | Yes (programmable gain, 1 to 128) | Programmable gain allows direct connection of low-level sensors without external amplification. |
| Target application focus | Multichannel industrial measurement / data acquisition | Weigh scales / bridge sensors | Application focus indicates whether the part's feature set (channel count, filtering, rate) matches the intended use case. |
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 | AD7739BRUZ | AD7730BRU-REEL |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Part Status | Active | Obsolete |
| Number of Bits | 24 | 24 |
| Number of Channels | - | 1 |
| Power (Watts) | - | 125 mW |
| Voltage - Supply, Analog | 5V | 5V |
| Voltage - Supply, Digital | 2.7V ~ 3.6V, 5V | 2.7V ~ 5.25V |
| Mounting Type | - | Surface Mount |
| Sampling Rate(Per Second) | 15.1k | - |
| Number of Inputs | 4, 8 | - |
| Input Type | Differential, Single Ended | - |
| Data Interface | SPI, DSP | - |
| Configuration | MUX-ADC | - |
| Number of A/D Converters | 1 | - |
| Architecture | Sigma-Delta | - |
| Reference Type | External | - |
| Features | True Bipolar | - |
| Operating Temperature | -40°C ~ 105°C | - |
Frequently asked questions
What are the primary functional differences between the AD7739BRUZ and the AD7730BRU-REEL?
The AD7739BRUZ is a 24-bit, 8-channel, low-voltage sigma-delta ADC designed for high-throughput multiplexed applications, while the AD7730BRU-REEL is a 24-bit, 2-channel sigma-delta ADC optimized specifically for weigh-scale and pressure-sensor applications with built-in AC excitation and a programmable gain front end. The AD7739 offers more input channels and faster channel switching, whereas the AD7730 provides dedicated bridge-sensor features.
Are the AD7739BRUZ and AD7730BRU-REEL pin-compatible?
No. Both devices are offered in 24-lead TSSOP packages, but their pin functions and internal signal routing differ because the AD7739 provides 8 differential input channels and the AD7730 provides 2 differential channels with dedicated AC excitation and bridge-drive pins. They are not drop-in replacements for each other.
What is the maximum output data rate of each device?
The AD7739BRUZ supports output data rates up to 15.4 kSPS in its fast mode. The AD7730BRU-REEL supports output update rates up to 200 Hz in its standard configuration, with higher rates available in chop-disabled modes per the datasheet. The AD7739 is therefore better suited to higher-throughput multiplexed systems.
Which device is better suited for weigh-scale or bridge-sensor designs?
The AD7730BRU-REEL is specifically designed for weigh-scale and pressure-sensor applications. It integrates a programmable gain front end, AC excitation for ratiometric bridge measurements, and a burnout-current detection feature. The AD7739BRUZ lacks these dedicated bridge-sensor features and is intended for general-purpose multichannel signal acquisition.
Do both devices support the same supply voltage range?
Both devices operate from a single 5 V analog supply with a separate 3 V or 5 V digital supply, per their respective datasheets. However, the AD7739BRUZ is specified for operation with an AVDD of 5 V and a DVDD of 3 V or 5 V, while the AD7730BRU-REEL is specified for AVDD of 5 V and DVDD of 3 V or 5 V. Designers should confirm exact limits in the manufacturer datasheets before finalizing the supply design.
Can the AD7739BRUZ replace the AD7730BRU-REEL in an existing weigh-scale design?
Not directly. The AD7730BRU-REEL includes AC excitation outputs, a dedicated bridge-drive circuit, and burnout detection that the AD7739BRUZ does not provide. Replacing the AD7730 with the AD7739 would require redesigning the excitation and bridge-interface circuitry and revalidating the signal chain against the target accuracy and noise specifications.
What are the package and ordering differences between the two part numbers?
Both parts are supplied in 24-lead TSSOP packages. The AD7739BRUZ suffix indicates a lead-free, RoHS-compliant tube or tray ordering option, while the AD7730BRU-REEL suffix indicates a tape-and-reel packaging option for automated assembly. The "-REEL" designation refers to packaging format, not a different silicon die.