Beskrivning
Digital potentiometer, 4st 100kohm. 8-bitars upplösning ger 256 diskreta steg (flera potentiometrar kan kopplas ihop externt för högre upplösning, se datablad för mer information). Kretsen styrs via SPI och spänningsmatas med +2.7 till +5.5V.
The AD8403 provide a quad-channel, 256-position, digitally controlled variable resistor (VR) device. These devices perform the same electronic adjustment function as a mechanical potentiometer or variable resistor. The AD8403 contains four independent variable resistors in 24-lead SOIC package. Each part contains a fixed resistor with a wiper contact that taps the fixed resistor value at a point determined by the digital code loaded into the controlling serial input register. The resistance between the wiper and either endpoint of the fixed resistor varies linearly with respect to the digital code transferred into the VR latch. Each variable resistor offers a completely programmable value of resistance between the A terminal and the wiper or the B terminal and the wiper. The fixed A-to-B terminal resistance of 100 kO has a ±1% channel-to-channel matching tolerance with a nominal temperature coefficient of 500 ppm/°C. A unique switching circuit minimizes the high glitch inherent in traditional switched resistor designs, avoiding any make-before-break or break-before-make operation.
