Analog Devices Inc./Maxim Integrated DS1847B-050+T&R

Overview

DS1847B-050+T&R from Maxim Integrated is a dual temperature-controlled nonvolatile variable resistor IC featuring one 50kΩ and one 10kΩ linear-taper digital potentiometer, each with 256 positions, controlled via a 2-wire (I²C-compatible) interface and calibrated to change resistance every 2°C across –40°C to +95°C. It integrates a 13-bit 2's complement digital temperature sensor and stores resistor settings in EEPROM for bias voltage/current compensation in precision analog control circuits.

For engineers reviewing the DS1847B-050+T&R datasheet, DS1847B-050+T&R pinout, DS1847B-050+T&R application, or DS1847B-050+T&R equivalent, this device delivers deterministic, temperature-addressed resistance tuning without external calibration components - critical for laser diode biasing, sensor signal conditioning, and programmable gain amplifier trimming where thermal drift must be actively compensated.

Technical Context

The DS1847B-050+T&R implements two independent digitally controlled resistors driven by a shared on-chip temperature sensor; resistor values are selected from 72×8-bit EEPROM look-up tables (LUTs), each indexed at 2°C intervals over the full operating range. Each LUT entry corresponds to a specific 8-bit wiper position (00h–FFh), enabling precise per-temperature resistance mapping.

It operates as an I²C slave device with configurable 7-bit address (A2/A1/A0), supports both Standard (100 kHz) and Fast Mode (400 kHz) timing, and features write protection via the WP pin. The internal temperature sensor provides 0.0625°C resolution (13-bit output), updated every 10 ms, and feeds directly into LUT addressing logic without host intervention.

Key Specifications

Pinout & Package

DS1847B-050+T&R is housed in a 16-ball CSBGA package (4 mm × 4 mm, 0.5 mm pitch), optimized for space-constrained PCB layouts and thermal performance in embedded analog systems.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual digital potentiometer applications.

Compared with MAX5487ETE+ and AD5272BRMZ-50, DS1847B-050+T&R uniquely integrates dual-resistor topology, on-die temperature sensing, and EEPROM-based LUTs - enabling fully autonomous, self-contained thermal compensation without host processor involvement or additional analog components.

Availability

DS1847B-050+T&R is available at Aetrix Electronics and suitable for laser diode biasing, sensor signal conditioning, programmable gain amplifiers, industrial DAC trimming, and temperature-critical analog control systems requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for DS1847B-050+T&R 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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for industrial, communications, and computing applications, emphasizing integration, reliability, and thermal robustness.

The DS1847B-050+T&R belongs to Maxim's temperature-aware programmable resistor family, engineered specifically for closed-loop analog compensation in environments where passive component drift undermines system accuracy - delivering deterministic, EEPROM-backed thermal response without external calibration hardware.

FAQ

What is the function of the WP pin on the DS1847B-050+T&R?

The WP (Write Protect) pin on the DS1847B-050+T&R is an active-low input that disables all writes to EEPROM, control registers, and look-up tables when held high (logic 1) or left floating (internally pulled up). When pulled low (logic 0), it enables full read/write access via the 2-wire interface. This allows safe field updates while preventing accidental corruption during normal operation - a critical safeguard for DS1847B-050+T&R deployments in unattended systems.

How does the DS1847B-050+T&R achieve temperature compensation without external components?

The DS1847B-050+T&R achieves autonomous temperature compensation using its integrated 13-bit digital temperature sensor and two 72×8-bit EEPROM look-up tables (LUTs). The sensor measures die temperature every 10 ms, and the internal logic automatically selects the appropriate 8-bit wiper setting from the LUTs - one entry per 2°C increment across –40°C to +95°C. No external thermistor, ADC, or microcontroller is required for DS1847B-050+T&R to execute real-time resistance adjustment.

Can the DS1847B-050+T&R operate from a 3.3 V supply?

Yes, the DS1847B-050+T&R is fully specified to operate from a 3.0 V to 5.5 V supply, making it compatible with standard 3.3 V logic systems. All electrical characteristics - including I²C timing, EEPROM write endurance, resistor linearity, and temperature sensor accuracy - are guaranteed across this range. The DS1847B-050+T&R draws only 0.5–1.0 mA typical supply current at 3.3 V, supporting low-power industrial and battery-backed applications.

What is the difference between DS1847B-050+T&R and DS1847E-050/T&R?

The DS1847B-050+T&R uses a 16-ball CSBGA package (4 mm × 4 mm) with lead-free (RoHS-compliant) finish and tape-and-reel packaging (+T&R), whereas DS1847E-050/T&R uses a 14-pin TSSOP (173-mil) package with tape-and-reel. Both share identical electrical specifications, resistor values (50kΩ/10kΩ), temperature range (–40°C to +95°C), and functional behavior. The choice depends on PCB layout requirements: DS1847B-050+T&R offers smaller footprint and better thermal performance; DS1847E-050/T&R suits through-hole or legacy surface-mount assembly.

How many unique resistance values can the DS1847B-050+T&R provide per resistor?

The DS1847B-050+T&R provides 256 discrete resistance values per resistor (00h–FFh), corresponding to 256 wiper positions across the full end-to-end resistance range. Each position maps to a specific ohmic value stored in the respective 72-entry look-up table - with one entry assigned per 2°C temperature step from –40°C to +95°C. While only 72 entries are temperature-addressed, all 256 positions remain accessible in manual mode (via F0h/F1h registers), giving full 8-bit resolution for DS1847B-050+T&R configuration flexibility.