LTC1428-50 Series

The LTC1428-50 is a micropower 8-bit current sink output D/A converter (DAC) with an output range of 0µA to 50µA. In 3.3V or 5V systems, the DAC IOUTpin can be biased from 2V to 10V. Supply current is only 130µA. Shutdown mode drops the supply current to 0.2µA.The LTC1428-50 communicates with external circuitry by using one of three interface modes: standard 3-wire serial mode or one of two pulse modes. Upon power-up, the internal counter resets to 10000000B, the DAC output assumes midrange and the chip configures to 3-wire or pulse mode depending on theCSsignal level.In 3-wire mode, the system MPU can serially transfer 8-bit data to and from the LTC1428-50. In pulse mode, the upper six bits of the DAC output program for increment-only (1-wire interface) or increment/decrement (2-wire interface) operation depending on the DINsignal level. In increment-only mode, the counter rolls over and sets the DAC to zero if the counter increases beyond full scale. In increment/decrement mode, the counter stops incrementing at full scale, stops decrementing at zero scale and does not roll over.LTC1428-50 is available in an 8-pin SO package.ApplicationsLCD Contrast ControlBacklight Brightness ControlPower Supply Voltage AdjustmentBattery Charger Voltage/Current AdjustmentGaAs FET Bias AdjustmentTrimmer Pot Elimination