Analog Devices Inc./Maxim Integrated DS1806-100+

Overview

DS1806-100+ from Analog Devices (formerly Dallas Semiconductor) is a six-channel, digitally controlled, solid-state linear potentiometer with 100 kΩ end-to-end resistance per channel, 64-position resolution, ±0.5 LSB absolute linearity, and industrial temperature range (-40°C to +85°C). It serves as a precision analog adjustment element in programmable gain/attenuation circuits, sensor calibration paths, and mixed-signal trimming applications.

For engineers reviewing the DS1806-100+ datasheet, DS1806-100+ pinout, DS1806-100+ application, or DS1806-100+ equivalent, key selection considerations include its 3-wire serial interface with cascade capability, shared low-terminal architecture (L1–3 and L4–6), wiper resistance of 400–1000 Ω, and compatibility with 2.7–5.5 V supply rails.

Technical Context

The DS1806-100+ implements six independent 64-step resistor arrays, each controlled by an 8-bit register where bits 0–5 set wiper position and bits 6–7 enable "don't change" functionality. Its 48-bit I/O shift register supports LSB-first serial loading via RST/CLK/DIN with COUT for daisy-chaining.

Operation requires RST high to activate the 3-wire port; wipers power up at position 0 (LX). The device supports bidirectional read/write through optional feedback resistor configuration, enabling full 48-bit data loopback across cascaded units without external logic.

Key Specifications

Pinout & Package

DS1806-100+ is packaged in a 20-pin DIP (300-mil) with through-hole mounting and standard 0.3-inch width. Pin numbering follows dual-in-line convention with pin 1 at top-left corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digitally controlled potentiometer applications.

Compared with AD5206BRUZ-100 and MCP42100-E/P, the DS1806-100+ uniquely supports hardware daisy-chaining via COUT, simplifies multi-device wiring, and maintains consistent 64-step resolution with tighter absolute linearity (±0.5 LSB vs. ±1 LSB typical), making it optimal for synchronized analog trimming where inter-device coordination matters.

Availability

DS1806-100+ is available at Aetrix Electronics and suitable for programmable gain amplifiers, sensor calibration systems, audio balance networks, and DC power supply trim circuits requiring stable component supply, long-term obsolescence management, and industrial-grade reliability.

Supply support for DS1806-100+ 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 acquired Dallas Semiconductor in 2001 and maintains legacy product support including the DS1806 family. The company specializes in high-performance analog, mixed-signal, and digital signal processing technologies.

The DS1806-100+ belongs to the Digital Potentiometer product line, designed specifically for replacing mechanical trimmers in automated calibration, closed-loop control, and adaptive analog signal conditioning systems.

FAQ

What is the maximum clock frequency supported by the DS1806-100+ serial interface?

The DS1806-100+ supports a maximum CLK frequency of 10 MHz, as specified in its AC Electrical Characteristics table. This allows full 48-bit register updates in under 5 µs, enabling rapid recalibration cycles in real-time systems. Timing margins remain valid across the full -40°C to +85°C operating range and 2.7–5.5 V supply voltage window. The DS1806-100+ does not require external clock conditioning circuitry for compliant operation at this rate.

Does the DS1806-100+ support reading back wiper positions from the device?

Yes, the DS1806-100+ supports bidirectional communication via its COUT pin and optional feedback resistor configuration. When RST goes high, the LSB of potentiometer 1 appears on COUT and can be fed back to DIN through a 1–10 kΩ isolation resistor. After 48 clock cycles, the original 48-bit wiper state returns to the controller. This read-back capability is intrinsic to the DS1806-100+ architecture and requires no additional ICs or firmware overhead beyond standard serial timing.

How are the low-end terminals arranged on the DS1806-100+?

The DS1806-100+ uses grouped low-terminal architecture: pins L1–3 serve as the shared low-end connection for potentiometers 1, 2, and 3, while pins L4–6 serve potentiometers 4, 5, and 6. This design reduces pin count and PCB routing complexity versus fully independent terminals. Each group must be connected to a common reference (e.g., GND or bias voltage), and mixing groups within one potentiometer channel is not permitted. The DS1806-100+ datasheet confirms this mapping applies identically across all resistance versions including DS1806-100+.

Can the DS1806-100+ operate from a 3.3 V supply?

Yes, the DS1806-100+ operates reliably from a 3.3 V supply, as confirmed by its Recommended DC Operating Conditions table specifying VCC min = 2.7 V and max = 5.5 V. Input logic thresholds (VIH = 2.0 V min, VIL = 0.6 V max at 3.0 V ±10%) ensure clean interfacing with 3.3 V microcontrollers. Supply current remains within spec (ICC = 1.3–2.0 mA active, ISTBY = 12 µA), and all analog performance parameters-including linearity and wiper resistance-are guaranteed across this voltage range. The DS1806-100+ requires no external level-shifting components for 3.3 V system integration.

What is the purpose of the "don't change" bits in the DS1806-100+ wiper registers?

The "don't change" bits (bits 6 and 7) in each 8-bit wiper register allow selective update of individual potentiometers without disturbing others. When bits 6–7 = "11", the corresponding wiper position remains unchanged regardless of bits 0–5. This feature eliminates the need to read-modify-write the full 48-bit register, reducing bus traffic and preventing unintended changes during partial updates. It is a core architectural feature of the DS1806-100+ and directly enables efficient multi-channel trimming in dynamic systems.