TI ICL7121LCJI

The ICL7121 achieves 0.003% linearity without laser trimming by combining a four-quadrant multiplying DAC using thin-film resistors with an on-chip PROM-controlled correction circuit. Silicon-gate CMOS circuitry keeps power consumption extremely low. A standard memory write cycle timing and control simplifies the microprocessor bus interface. The input buffer register loads 16-bit input and directly controls the output switches. The register is transparent when WR and CS are held low. The ICL7121 is designed and programmed for bipolar operation. An offset resistor at the output, which should be connected to -VREF, along with an inverter on the MSB line, gives the DAC a two's complement bipolar transfer function. Two additional resistors are included on-chip to facilitate reference inversion, so only a single external op-amp is required.