Analog Devices AD7846 Product Info

• 16-bit monotonicity over temperature
• ±2 LSBs integral linearity error
• Microprocessor compatible with readback capability
• Unipolar or bipolar output
• Multiplying capability
• Low power (100 mW typical)

The AD7846 is a 16-bit DAC constructed with the Analog Devices, Inc., LC²MOS process. It has V_REF+ and V_REF− reference inputs and an on-chip output amplifier. These can be configured to give a unipolar output range (0 V to +5 V, 0 V to +10 V) or bipolar output ranges (±5 V, ±10 V).

The DAC uses a segmented architecture. The four MSBs in the DAC latch select one of the segments in a 16-resistor string. Both taps of the segment are buffered by amplifiers and fed to a 12-bit DAC, which provides a further 12 bits of resolution. This architecture ensures 16-bit monotonicity. Excellent integral linearity results from tight matching between the input offset voltages of the two buffer amplifiers.

In addition to the excellent accuracy specifications, the AD7846 also offers a comprehensive microprocessor interface. There are 16 data I/O pins, plus control lines (CS, R/W, LDAC and CLR). R/W and CS allow writing to and reading from the I/O latch.

This is the readback function, which is useful in ATE applications. LDAC allows simultaneous updating of DACs in a multi-DAC system and the CLR line will reset the contents of the DAC latch to 00…000 or 10…000 depending on the state of R/W.

This means that the DAC output can be reset to 0 V in both the unipolar and bipolar configurations.

The AD7846 is available in 28-lead plastic, ceramic, and PLCC packages.

Product Highlights

1. 16-Bit Monotonicity