Part A
AD8400ARZ1
ADI公司
- Lifecycle
- Active
- Stock
- 4740 件
- Package
- SOIC-8
- Series
- 資料獲取-數位電位器
Replacement verdict
Not a drop-in replacement
The AD8400ARZ1 and AD8402AR1 are both single-channel digital potentiometers from the AD840x family, but they differ in resolution, package, and interface configuration, so they are not interchangeable in a design without validation. The AD8400ARZ1 offers 1 kΩ end-to-end resistance in an 8-lead SOIC package, while the AD8402AR1 provides 1 kΩ resistance in a 14-lead SOIC package with a different internal architecture. Designers must verify footprint, resolution, and interface compatibility before considering substitution.
Different package footprint
Different resolution
Different interface configuration
Different channel architecture
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 | AD8402AR1 | Why it matters |
|---|---|---|---|
| Number of Resistor Channels | 1 | 2 | Determines how many independent digital potentiometer channels are available; a single-channel part cannot replace a dual-channel part in circuits requiring two adjustable resistances. |
| End-to-End Resistance | 1 kΩ | 1 kΩ | Sets the nominal full-scale resistance range; matching values ensures the same adjustment span and current levels in the target circuit. |
| Resolution (Number of Positions) | 256 positions (8-bit) | 256 positions (8-bit) | Defines the step granularity of resistance adjustment; identical resolution preserves the same wiper step size and control precision. |
| Digital Interface | SPI (3-wire serial) | SPI (3-wire serial) | The communication protocol must match the host controller; both use the same serial interface, allowing firmware reuse. |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | Determines compatibility with the system power rail; identical ranges allow operation in the same voltage domain. |
| Package / Mounting | 8-lead SOIC (surface mount) | 14-lead SOIC (surface mount) | Footprint and pin count differ, so the PCB layout must accommodate the larger 14-lead package for the dual-channel device. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Confirms both parts are rated for the same industrial temperature environment, ensuring reliable operation under identical conditions. |
| Wiper Current Rating | 5 mA (typical max) | 5 mA (typical max) | Limits the load current the wiper can handle; matching ratings ensures the same drive capability for the connected load. |
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 | AD8402AR1 |
|---|---|---|
| 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 | 1k |
| Interface | SPI | SPI |
| Memory Type | Volatile | Volatile |
| Voltage - Supply | 2.7V ~ 5.5V | 2.7V ~ 5.5V |
| Tolerance | ±33% | ±33% |
| 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 AD8402AR1 digital potentiometers?
The AD8400ARZ1 is a single-channel, 1 kΩ digital potentiometer in an 8-lead SOIC package, while the AD8402AR1 is a dual-channel, 1 kΩ digital potentiometer in a 14-lead SOIC package. Both are 256-position devices from Analog Devices with an SPI-compatible serial interface, but they differ in channel count and package pin count.
Are the AD8400ARZ1 and AD8402AR1 pin-compatible?
No. The AD8400ARZ1 uses an 8-lead SOIC package, whereas the AD8402AR1 uses a 14-lead SOIC package. The different pin counts and pinouts mean they are not drop-in replacements for each other and require different PCB footprints.
What is the end-to-end resistance of both devices?
Both the AD8400ARZ1 and AD8402AR1 are the 1 kΩ resistance option in the AD8400/AD8402 family, offering 256 programmable positions (8-bit resolution) across the end-to-end resistance.
Do both parts use the same digital interface?
Yes. Both the AD8400ARZ1 and AD8402AR1 use a 3-wire SPI-compatible serial interface (SDI, SDO, and CLK) with a chip select input, allowing daisy-chaining and microcontroller control. The AD8402AR1 provides independent control of two channels through the same interface.
What supply voltage range do the AD8400ARZ1 and AD8402AR1 support?
Both devices operate from a single supply of 2.7 V to 5.5 V, making them suitable for low-voltage digital control applications. They also feature a power-on reset that sets the wiper to midscale.
When should I choose the AD8402AR1 over the AD8400ARZ1?
Choose the AD8402AR1 when your design requires two independently programmable resistance channels in a single package, such as dual gain control or stereo level adjustment. Choose the AD8400ARZ1 when only one channel is needed and board space is limited, since it occupies a smaller 8-lead SOIC footprint.
Are both devices available in the same operating temperature range?
Yes. Both the AD8400ARZ1 and AD8402AR1 are specified for the industrial temperature range of −40 °C to +85 °C, as documented in the Analog Devices AD8400/AD8402/AD8403 datasheet.