Overview
The AD8400AR10, produced by Analog Devices Inc., is a single-channel, 256-position digitally controlled variable resistor (VR) device. This component performs the same electronic adjustment function as a mechanical potentiometer or variable resistor. It is available in a compact 8-lead SOIC package and operates over a single-supply voltage range of 2.7 V to 5.5 V. The device is designed for applications requiring precise digital control over resistance values, offering a fixed resistor with a wiper contact that taps the fixed resistor value based on a digital code loaded into the controlling serial input register.
Key Specifications
| Parameter | Symbol | Conditions | Min | Max | Unit | |
|---|---|---|---|---|---|---|
| Nominal Resistance | RAB | TA = 25°C, model: AD840XYY10 | 8 | 10 | 12 | kΩ |
| Resistance Tempco | ΔRAB/ΔT | VAB = VDD, wiper = no connect | 500 ppm/°C | |||
| Wiper Resistance | RW | VDD = 5V, IW = VDD/RAB | 50 | 100 | Ω | |
| Power Dissipation (CMOS) | PDISS | VIH = VDD or VIL = 0 V, VDD = 5.5 V | 27.5 μW | |||
| Power Shutdown Current | < 5 μA | |||||
| Operating Temperature Range | -40°C | +125°C |
Key Features
- Single-channel, 256-position digitally controlled variable resistor (VR) device.
- Available in 8-lead SOIC package.
- Single-supply operation: 2.7 V to 5.5 V.
- 3-wire, SPI-compatible serial data input with 10 MHz update data loading rate.
- Power shutdown feature with less than 5 μA current consumption.
- Midscale preset via reset (RS) pin.
- Extended industrial temperature range: −40°C to +125°C.
- Channel-to-channel matching tolerance of ±1% and nominal temperature coefficient of 500 ppm/°C.
Applications
- Mechanical potentiometer replacement.
- Programmable filters, delays, and time constants.
- Volume control and panning.
- Line impedance matching.
- Power supply adjustment.
Q & A
- What is the AD8400AR10 used for?
The AD8400AR10 is used as a single-channel, 256-position digitally controlled variable resistor, replacing mechanical potentiometers and providing precise digital control over resistance values.
- What are the available resistance values for the AD8400AR10?
The AD8400AR10 is available with fixed resistor values of 1 kΩ, 10 kΩ, 50 kΩ, and 100 kΩ.
- What is the operating voltage range of the AD8400AR10?
The AD8400AR10 operates over a single-supply voltage range of 2.7 V to 5.5 V.
- How does the power shutdown feature work?
The power shutdown feature forces the resistor to an end-to-end open-circuit condition on the A terminal and shorts the wiper to the B terminal, achieving a microwatt power shutdown state with less than 5 μA current consumption.
- What is the temperature coefficient of the AD8400AR10?
The nominal temperature coefficient of the AD8400AR10 is 500 ppm/°C.
- Can the AD8400AR10 be used in automotive applications?
Yes, the AD8400AR10 is qualified for automotive applications.
- What is the maximum update data loading rate for the AD8400AR10?
The maximum update data loading rate for the AD8400AR10 is 10 MHz.
- How does the reset (RS) pin function?
The reset (RS) pin forces the wiper to midscale by loading 80H into the VR latch.
- What is the operating temperature range of the AD8400AR10?
The AD8400AR10 operates over an extended industrial temperature range of −40°C to +125°C.
- Can multiple AD8400AR10 devices be daisy-chained?
Yes, multiple AD8400AR10 devices can be daisy-chained using the serial data output pin without additional external decoding logic.
