Part A
AD8400ARZ1
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4740 PCS
- Package
- SOIC-8
- Series
- Acquisição de dados - Potenciômetros Digitais
Replacement verdict
Not a drop-in replacement
The AD8400ARZ1 and AD8402AR100 are not drop-in replacements for each other. The AD8400ARZ1 is a single-channel digital potentiometer with a 1 kΩ end-to-end resistance, while the AD8402AR100 is a dual-channel device with a 100 kΩ resistance. These differences in channel count and resistance value, combined with differing package and pinout configurations, mean the two parts are not functionally interchangeable in a given design without circuit redesign and validation.
Different channel count
Different resistance value
Different package and pinout
Different interface configuration
Parts at a glance
Part B
AD8402AR100
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 6475 PCS
- Package
- SOIC-14
- Series
- Acquisição de dados - Potenciômetros Digitais
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8400ARZ1 | AD8402AR100 | Why it matters |
|---|---|---|---|
| Number of Resistor Channels | 1 | 2 | Determines how many independent programmable resistance paths are available; a single-channel part cannot replace a dual-channel part in circuits needing two independent adjustments. |
| End-to-End Resistance | 1 kΩ | 100 kΩ | Sets the nominal resistance range of the digital potentiometer; a 100x difference drastically changes the current and voltage scaling in the application circuit. |
| Resolution | 8-bit (256 positions) | 8-bit (256 positions) | Defines the number of discrete wiper steps; matching resolution means both offer the same adjustment granularity. |
| Digital Interface | SPI (3-wire serial) | SPI (3-wire serial) | Determines how the host controller communicates with the device; identical SPI interfaces allow reuse of the same firmware and bus wiring. |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Defines the operating voltage window; matching ranges ensure compatibility with the same system power rail. |
| Package | 8-lead SOIC | 14-lead SOIC | Affects PCB footprint and pin count; different packages require layout changes and cannot be drop-in substituted. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Specifies the environmental range over which the device is guaranteed to operate; matching ranges suit the same application environments. |
| Wiper Settling / Update Rate | SPI clock up to 10 MHz | SPI clock up to 10 MHz | Governs how fast the wiper position can be updated; identical serial clock support means comparable dynamic adjustment performance. |
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 | AD8400ARZ1 | AD8402AR100 |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| Taper | Linear | Linear |
| Configuration | Potentiometer | Potentiometer |
| Number of Circuits | 1 | 2 |
| Number of Taps | 256 | 256 |
| Resistance(Ohms) | 1k | 100k |
| 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 |
Frequently asked questions
What are the key differences between the AD8400ARZ1 and AD8402AR100?
The AD8400ARZ1 is a single-channel, 1 kΩ digital potentiometer in an 8-lead SOIC package, while the AD8402AR100 is a dual-channel, 100 kΩ digital potentiometer in a 14-lead SOIC package. They differ in number of channels, end-to-end resistance, package size, and pin count.
Are the AD8400ARZ1 and AD8402AR100 pin-compatible?
No. The AD8400ARZ1 uses an 8-lead SOIC package, whereas the AD8402AR100 uses a 14-lead SOIC package. The different pin counts and pin functions prevent direct pin-to-pin compatibility.
What is the end-to-end resistance of each device?
The AD8400ARZ1 has a 1 kΩ end-to-end resistance, and the AD8402AR100 has a 100 kΩ end-to-end resistance. The resistance value is indicated by the suffix in each part number.
How many potentiometer channels does each part provide?
The AD8400ARZ1 provides one single-channel digital potentiometer, while the AD8402AR100 provides two independent channels in a single package.
Do both parts use the same digital interface?
Yes. Both the AD8400 and AD8402 families use a 3-wire SPI-compatible serial interface for programming the wiper position, allowing similar host-side firmware control.
Can the AD8400ARZ1 be used as a drop-in replacement for the AD8402AR100?
No. The AD8400ARZ1 is single-channel with 1 kΩ resistance in an 8-lead package, while the AD8402AR100 is dual-channel with 100 kΩ resistance in a 14-lead package. Channel count, resistance, and footprint differences prevent a direct drop-in replacement.
What supply voltage range do these digital potentiometers support?
Both the AD8400 and AD8402 families operate from a single 2.7 V to 5.5 V supply, making them suitable for low-voltage digital control applications.
How many wiper positions are available on each device?
Both the AD8400ARZ1 and AD8402AR100 provide 256-position wiper settings, programmable via the serial interface.