Analog Devices Inc./Maxim Integrated DS1620+

Overview

DS1620+ from Maxim Integrated is a digital thermometer and thermostat IC with integrated temperature sensor, 3-wire serial interface, and three independent thermal alarm outputs (THIGH, TLOW, TCOM). It delivers ±0.5°C accuracy from 0°C to +70°C, measures -55°C to +125°C in 0.5°C increments, converts temperature in ≤750ms, and stores user-defined trip points nonvolatily in EEPROM. It serves as a self-contained thermal monitoring and control solution in embedded systems without requiring external components.

For engineers reviewing the DS1620+ datasheet, DS1620+ pinout, DS1620+ application, or DS1620+ equivalent, this page provides verified technical context, exact pin functions, real-world use cases in thermostatic control and industrial sensing, and confirmed alternative parts with documented functional and application-level differences.

Technical Context

The DS1620+ uses a bandgap-based temperature sensor and outputs readings as a 9-bit two's complement value representing temperature in 0.5°C LSB steps. Conversion is initiated via 3-wire command (EEh) or stand-alone CONV pulse on CLK/CONV pin when CPU=0.

Thermostat operation relies on two independently programmable EEPROM registers (TH and TL) that drive THIGH (≥TH), TLOW (≤TL), and TCOM (high between TH and TL). The configuration register controls continuous vs. one-shot mode, CPU/standalone behavior, and status flags (DONE, THF, TLF, NVB).

Key Specifications

Pinout & Package

DS1620+ is supplied in lead-free 8-pin DIP (300-mil) package, compatible with through-hole PCB assembly and legacy socketing. Pin spacing and footprint match industry-standard 0.3" DIP layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital thermometer and thermostat applications.

Compared with DS1620+, MAX31820 trades hardware alarm outputs for 1-Wire scalability and finer resolution, while LM75B sacrifices autonomous operation and accuracy for I²C compatibility and lower unit cost-neither offers the DS1620+'s combination of 3-wire simplicity, EEPROM-stored thresholds, and three dedicated thermal outputs.

Availability

DS1620+ is available at Aetrix Electronics and suitable for thermostatic controls, industrial temperature monitoring, and consumer appliance safety applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for DS1620+ 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 digital ICs for industrial, automotive, communications, and computing markets.

The DS1620+ belongs to Maxim's legacy temperature-sensing portfolio, engineered for embedded thermal management where autonomous, low-component-count, and nonvolatile configurability are critical design requirements.

FAQ

What is the operating temperature range of the DS1620+?

The DS1620+ operates across -55°C to +125°C. Its temperature measurement range matches this span, delivering readings in 0.5°C increments throughout. Accuracy is specified as ±0.5°C from 0°C to +70°C at VDD ≥ 3.0V, degrading to ±2.0°C over the full range. This makes DS1620+ suitable for harsh environments like motor control enclosures and outdoor industrial sensors.

Does the DS1620+ require external components to function?

No, the DS1620+ requires no external components for basic operation. It integrates a bandgap temperature sensor, ADC, EEPROM for TH/TL storage, and digital logic-all powered from a single 2.7V–5.5V supply. Pull-up resistors on DQ and RST are recommended for reliable 3-wire communication but are not strictly mandatory in short-trace, low-noise layouts. DS1620+ eliminates the need for op-amps, comparators, or external references.

How does the DS1620+ support standalone (microcontroller-less) operation?

The DS1620+ supports standalone operation via its CLK/CONV pin: when the CPU bit in the configuration register is set to 0, a brief low pulse (<10 ms) on CLK/CONV initiates a single temperature conversion, and a sustained low state triggers continuous conversions. THIGH, TLOW, and TCOM outputs respond autonomously based on EEPROM-stored thresholds-enabling DS1620+ to act as a complete thermal cutoff without any host processor.

What is the purpose of the TCOM output on the DS1620+?

The TCOM output on the DS1620+ provides hardware-based thermal window detection: it goes high when temperature reaches or exceeds TH and remains high until temperature falls below TL. This creates configurable hysteresis without software intervention. In DS1620+, TCOM enables fail-safe thermal containment-e.g., disabling a power stage while temperature is outside safe bounds and re-enabling only after confirmed cooldown-reducing firmware complexity and improving reliability.

Can the DS1620+ store temperature thresholds permanently?

Yes, the DS1620+ stores TH and TL trip points in on-chip EEPROM, retaining them across power cycles with guaranteed 10-year data retention and 50,000 write cycles. These values are written using Write TH (01h) and Write TL (02h) commands and read back via Read TH (A1h) and Read TL (A2h). This allows DS1620+ to be pre-programmed before system integration and used in field-deployed equipment without runtime configuration dependency.