Analog Devices Inc. AD7846KN

Overview

AD7846KN from Analog Devices is a 16-bit voltage-output DAC fabricated in LC2MOS technology, featuring ±2 LSB integral linearity error, 6 µs settling time to 0.006% FSR, and microprocessor-compatible interface with readback capability. It supports unipolar (0 V to +10 V) and bipolar (±10 V) output configurations via external reference and RIN pin control, and is used in precision closed-loop control, ATE systems, and position measurement circuits.

For engineers reviewing the AD7846KN datasheet, AD7846KN pinout, AD7846KN application, or AD7846KN equivalent, key selection considerations include guaranteed 16-bit monotonicity over temperature, on-chip deglitching (2.5 µs hold), dual-supply analog operation (±15 V), digital I/O latch readback, and configurable gain (×1 or ×2) via RIN connection.

Technical Context

The AD7846KN employs a segmented architecture: four MSBs select one of 16 segments in a resistor string, with both segment taps buffered and fed to a 12-bit interpolating DAC - ensuring 16-bit monotonicity without requiring 16-bit resistor matching. Tight offset voltage matching between the two buffer amplifiers enables excellent integral linearity (±4 LSB max for K-grade).

Its digital interface includes 16 bidirectional data lines (DB0–DB15), CS, R/W, LDAC, and CLR pins, supporting write-to-latch, read-from-latch, asynchronous DAC update, and zero-reset functionality. The output stage integrates a track-and-hold amplifier that holds VOUT for ~2.5 µs during LDAC-triggered updates to suppress glitch energy.

Key Specifications

Pinout & Package

The AD7846KN is housed in a 28-lead plastic DIP (PDIP) package with 0.6-inch body width and through-hole mounting. Pin 1 is identified by a notch or dot; pin numbering follows standard counter-clockwise convention when viewed from top.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit voltage-output DAC applications.

Compared with AD7846KN, AD7847KN extends temperature range and improves typical INL but retains identical pinout and interface, while AD5542AKRZ trades parallel control and dual supplies for smaller size and faster settling - making it a functional alternative only in newly designed serial systems.

Availability

AD7846KN is available at Aetrix Electronics and suitable for industrial closed-loop control, automated test equipment, position measurement systems, and calibration instrumentation requiring stable component supply across extended production lifecycles.

Supply support for AD7846KN includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design centers worldwide and a legacy of precision converter innovation since 1965.

The AD7846KN belongs to Analog Devices' precision voltage-output DAC product line, engineered specifically for applications demanding guaranteed monotonicity, microprocessor interfacing, and flexible unipolar/bipolar output configuration in industrial and test instrumentation.

FAQ

What is the operating temperature range for the AD7846KN?

The AD7846KN is specified for operation from 0°C to +70°C (commercial grade). This range is confirmed in the Absolute Maximum Ratings table and applies to all electrical specifications unless otherwise noted. The K-suffix denotes this temperature grade, distinct from the A-grade (−40°C to +85°C) version. For designs requiring wider ambient tolerance, the AD7847KN is the direct temperature-extended variant of the AD7846KN.

Does the AD7846KN support both unipolar and bipolar output configurations?

Yes, the AD7846KN supports both unipolar (e.g., 0 V to +10 V) and bipolar (e.g., ±10 V) outputs. Configuration is achieved by setting VREF− to 0 V (unipolar) or −5 V (bipolar) and connecting the RIN pin to either VOUT (gain = 1) or ground (gain = 2). Table 6 in the datasheet explicitly lists these combinations, and Figure 23 and Figure 24 provide verified schematic implementations for each mode.

How does the readback function work on the AD7846KN?

The AD7846KN's readback function allows reading the current contents of its 16-bit DAC latch via the DB0–DB15 bus. To activate, assert CS low and R/W high - the latch data appears on the data lines within t12 (120 ns max). This feature is documented in the Functional Block Diagram, Control Logic Truth Table (Table 7), and General Description, and is especially valuable in ATE systems for verifying loaded values without external measurement.

What is the purpose of the LDAC pin on the AD7846KN?

The LDAC (Load DAC) pin is an asynchronous strobe that transfers data from the input latch to the DAC latch, causing the corresponding analog output to appear at VOUT. When LDAC is low, the output updates immediately upon data write; when pulsed low, it enables synchronized updating across multiple AD7846KN devices in multi-DAC systems. Its timing is defined in Table 3 (t11 = 70 ns min pulse width), and its deglitching action is detailed in Figure 22 and the Output Stage section.

Can the AD7846KN operate with supply voltages other than ±15 V and +5 V?

Yes, the AD7846KN functions with VDD = +11.4 V to +15.75 V, VSS = −11.4 V to −15.75 V, and VCC = +4.75 V to +5.25 V. The datasheet confirms functionality at ±12 V supplies in the Power Requirements footnote, and Figure 18/19 show INL/DNL performance across VDD/VSS variation. However, output voltage swing scales with supply rails (VSS + 4 V to VDD − 3 V), so reduced supplies proportionally limit output range.