Part A
AD8403ARUZ1
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2995 PCS
- Package
- TSSOP-24
- Series
- Data Acquisition - Digital Potentiometers
Replacement verdict
Not a drop-in replacement
The AD8403ARUZ1 and AD8402ARU50 are not drop-in replacements for each other. Although both are quad/dual-channel digital potentiometers from the same AD840x family in TSSOP packages, they differ in channel count, end-to-end resistance, and interface configuration, so a direct substitution is not possible without circuit and firmware redesign.
Different channel count
Different end-to-end resistance
Different interface configuration
Different package pinout
Parts at a glance
Part B
AD8402ARU50
Công ty Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 3284 PCS
- Package
- TSSOP-14
- Series
- Data Acquisition - Digital Potentiometers
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8403ARUZ1 | AD8402ARU50 | Why it matters |
|---|---|---|---|
| Number of Resistor Channels | 4 | 2 | Determines how many independent digital potentiometer channels are available in a single package; a direct functional substitutability constraint. |
| End-to-End Resistance | 1 kΩ | 50 kΩ | Sets the nominal resistance range of the potentiometer, directly affecting the circuit's gain, attenuation, or current-setting behavior. |
| Resolution (Number of Positions) | 256 positions (8-bit) | 256 positions (8-bit) | Defines the number of discrete wiper steps and thus the achievable adjustment granularity. |
| Digital Interface | SPI (3-wire serial) | SPI (3-wire serial) | Determines the host communication protocol required to control the device; matching interfaces simplify drop-in replacement. |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Must be compatible with the system power rail for the device to operate correctly. |
| Package | TSSOP-24 | TSSOP-14 | Footprint and pin count affect PCB layout compatibility; different packages require board redesign. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Confirms suitability for the target application's environmental conditions. |
| Wiper Resistance | ~50 Ω (typical) | ~50 Ω (typical) | Adds series resistance in the signal path and affects accuracy, especially at low end-to-end resistance settings. |
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 | AD8403ARUZ1 | AD8402ARU50 |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| Part Status | Active | Obsolete |
| Taper | Linear | Linear |
| Configuration | Potentiometer | Potentiometer |
| Number of Circuits | 4 | 2 |
| Number of Taps | 256 | 256 |
| Resistance(Ohms) | 1k | 50k |
| Interface | SPI | SPI |
| Memory Type | Volatile | Volatile |
| Voltage - Supply | 2.7V ~ 5.5V | 2.7V ~ 5.5V |
| Tolerance | ±33% | ±30% |
| Temperature Coefficient(Typ) | 700ppm/°C | 500ppm/°C |
| Mounting Type | Surface Mount | Surface Mount |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 125°C |
| Features | Cascade Pin | - |
Frequently asked questions
What are the key differences between the AD8403ARUZ1 and AD8402ARU50?
The AD8403ARUZ1 is a quad-channel digital potentiometer with a 1 kΩ end-to-end resistance, while the AD8402ARU50 is a dual-channel device with a 50 kΩ end-to-end resistance. Both are 8-bit, SPI-compatible digital potentiometers from Analog Devices in 14-lead TSSOP packages, but they differ in channel count and nominal resistance.
Are the AD8403ARUZ1 and AD8402ARU50 pin-compatible?
No. Although both are offered in 14-lead TSSOP (RU) packages, the AD8403 is a quad-channel device and the AD8402 is a dual-channel device, so their pin functions and internal signal assignments differ. They should not be treated as drop-in replacements without verifying the pinout against the respective datasheets.
What is the resolution and interface of these digital potentiometers?
Both the AD8403ARUZ1 and AD8402ARU50 are 8-bit (256-position) digital potentiometers that use a 3-wire SPI-compatible serial interface for programming the wiper position.
How does the end-to-end resistance differ and why does it matter?
The AD8403ARUZ1 has a 1 kΩ nominal end-to-end resistance, whereas the AD8402ARU50 has a 50 kΩ nominal end-to-end resistance. The chosen resistance affects wiper current, power dissipation, and the loading of the circuit, so the value must be selected to match the application requirements.
Can the AD8402ARU50 replace the AD8403ARUZ1 in an existing design?
Not directly. The AD8402ARU50 provides only two channels versus four on the AD8403ARUZ1, and its 50 kΩ resistance differs from the 1 kΩ of the AD8403ARUZ1. A replacement requires validating channel count, resistance, pinout, and circuit behavior against the manufacturer datasheets.
What supply voltage range do these devices support?
Both the AD8403ARUZ1 and AD8402ARU50 operate from a single 2.7 V to 5.5 V supply, making them suitable for low-voltage digital control applications.
What are typical applications for these digital potentiometers?
These devices are commonly used for programmable gain and offset adjustment, volume and tone control, and other digitally controlled resistance trimming where an SPI interface is available. The AD8403ARUZ1 suits multi-channel trimming needs, while the AD8402ARU50 suits dual-channel, higher-resistance applications.