My Inquiry
My Account
Analog Devices Inc./Maxim Integrated DS1731U+T&R
- Part No.:
- DS1731U+T&R
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Analog and Digital Output
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
DS1731U+T&R.pdf
- Description:
- SENSOR DIGITAL -55C-125C 8UMAX
- Quantity:
- Payment:
- Shipping:
Inventory:3,676
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
DS1731U+T&R from Maxim Integrated is a high-precision digital thermometer and thermostat IC with ±1°C accuracy from -10°C to +85°C, 9–12-bit user-selectable resolution, and integrated nonvolatile TH/TL trip-point registers. It operates over -55°C to +125°C and communicates via I²C-compatible 2-wire bus, serving as a self-contained thermal monitoring solution in space-constrained embedded systems.
For engineers reviewing the DS1731U+T&R datasheet, DS1731U+T&R pinout, DS1731U+T&R application, or DS1731U+T&R equivalent, this page delivers verified technical context, confirmed pin functions, real-world thermal management use cases, and validated alternative options for industrial temperature sensing and thermostat control.
Technical Context
The DS1731U+T&R implements a bandgap-based temperature sensor with a delta-sigma ADC, delivering calibrated digital output in °C across its full operating range. Its thermostat logic compares each conversion result against user-programmed TH and TL thresholds stored in NV EEPROM, updating the push-pull TOUT pin accordingly.
It supports multidrop I²C operation (up to 8 devices) using address pins A0–A2, and features configurable conversion modes (one-shot or continuous), programmable TOUT polarity, and software power-on reset. All configuration bits except POL and 1SHOT are volatile SRAM; only TH, TL, POL, and 1SHOT persist through power cycles.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Temperature Accuracy | ±1°C over -10°C to +85°C at 3.0–5.5V - defines worst-case error bound for thermal alarm triggering in commercial environments. |
| Operating Range | -55°C to +125°C - enables deployment in harsh industrial or automotive under-hood locations without external compensation. |
| Resolution | User-selectable 9–12 bits (0.5°C to 0.0625°C step) - allows trade-off between measurement granularity and conversion time (93.75ms to 750ms). |
| I²C Interface | Standard-mode (400kHz max), open-drain SDA, push-pull TOUT - compatible with legacy microcontrollers without level-shifting or external pull-up tuning. |
| Nonvolatile Storage | TH/TL registers + POL/1SHOT bits in EEPROM (50k writes, 10-year retention) - permits pre-programming before soldering into final assembly. |
| Supply Current | 1mA active (temp conversion), 800nA standby - supports battery-powered portable products with multi-year runtime in low-duty-cycle monitoring. |
| Package | 8-pin µSOP (DS1731U+) - 3mm × 3mm footprint ideal for dense PCB layouts in routers, base stations, and handheld devices. |
Pinout & Package
DS1731U+T&R is housed in an 8-pin µSOP package (3mm × 3mm, 0.5mm pitch), optimized for automated surface-mount assembly and thermal performance in compact enclosures.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1: SDA | Data I/O for 2-wire serial interface | Open-drain bidirectional line requiring external pull-up; supports shared bus with up to 7 other DS1631/DS1631A/DS1731 devices. |
| 2: SCL | Clock input for 2-wire serial interface | CMOS-compatible input; master-generated clock synchronizes all read/write operations including TH/TL register access. |
| 3: TOUT | Thermostat output signal | Push-pull digital output reflecting current comparison status vs. TH/TL; polarity programmable via CONFIG register bit POL. |
| 4: GND | Analog/digital ground reference | Single ground connection required; no separate AGND/DGND - simplifies layout in mixed-signal applications. |
| 5: A2 | Device address bit MSB | Logic-level input (0 or VDD) sets bit A2 of 7-bit slave address (1001 A2 A1 A0), enabling unique addressing on shared I²C bus. |
| 6: A1 | Device address bit middle | Logic-level input sets bit A1; combined with A0/A2, allows up to eight uniquely addressed DS1731U+T&R units per bus segment. |
| 7: A0 | Device address bit LSB | Logic-level input sets bit A0; address pins are sampled at power-up and retained until next POR or reset. |
| 8: VDD | Power supply input | 2.7V–5.5V single supply powers analog sensor, ADC, EEPROM, and digital logic - eliminates need for voltage regulators in 3.3V or 5V systems. |
Key Features
| Feature | Design Value |
|---|---|
| Programmable thermostat with custom hysteresis | TH and TL trip points stored in NV EEPROM allow field-configurable thermal shutdown/restart behavior without firmware updates. |
| Self-contained operation mode | Unlike DS1631/DS1631A, DS1731 does not auto-start conversions at power-up - requires explicit Start Convert T command, ensuring deterministic initialization in safety-critical systems. |
| Two-wire (I²C) multidrop capability | Supports up to eight devices on one bus using hardware address pins - reduces MCU GPIO count and simplifies thermal monitoring across multiple PCB zones. |
| Temperature high/low flag tracking | THF and TLF bits in CONFIG register record historical excursions beyond TH/TL - enables post-event diagnostics without continuous polling. |
| Software power-on reset (POR) | 54h command resets all registers and stops conversions - provides safe recovery path during firmware hangs or communication errors. |
Applications
| Network Equipment Thermal Monitoring | Industrial Motor Control Cabinet Sensing |
|---|---|
|
Use Scenario: Real-time junction temperature tracking of FETs and power ICs inside 1U rack-mounted switches. IC Role / Device Role / Timing Role: Standalone digital thermometer providing periodic readings to host MCU via I²C; TOUT drives fan controller directly when threshold exceeded. Use Value: Eliminates analog signal conditioning and ADC routing; ±1°C accuracy ensures reliable thermal derating before MOSFET SOA limits are breached. |
Use Scenario: Ambient temperature supervision inside sealed motor drive enclosures exposed to variable ambient conditions. IC Role / Device Role / Timing Role: Primary thermostat device triggering HVAC activation or system shutdown based on sustained overtemperature events. Use Value: NV TH/TL registers retain alarm setpoints after power loss; push-pull TOUT drives relay directly without external buffer transistor. |
| Portable Medical Diagnostic Device | Automotive Infotainment Module |
|
Use Scenario: Battery compartment and sensor array thermal validation during clinical-grade handheld ultrasound operation. IC Role / Device Role / Timing Role: Low-power temperature logger sampling every 2 seconds in one-shot mode; data logged to flash memory upon excursion detection. Use Value: 800nA standby current extends battery life; 12-bit resolution captures subtle thermal gradients critical for calibration stability. |
Use Scenario: SoC die temperature monitoring in head-unit processors subjected to rapid ambient swings (-40°C to +85°C). IC Role / Device Role / Timing Role: Secondary thermal watchdog feeding interrupt to PMIC; TOUT asserts if internal SoC sensor fails or drifts. Use Value: -55°C to +125°C operating range exceeds AEC-Q100 Grade 3 requirements; EEPROM retention ensures alarm thresholds survive vehicle battery disconnect. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar digital thermometer and thermostat applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| DS1631U+ | ±0.5°C accuracy (0°C to +70°C); auto-starts conversions at power-up; same µSOP package and pinout. | Better accuracy in commercial temperature range; unsuitable where deterministic startup timing is required. | Select DS1631U+ when higher precision in office/server environments justifies tighter spec; verify power-up behavior aligns with system boot sequence. |
| LM75BIMM/NOPB | ±2°C accuracy (−25°C to +100°C); no NV TH/TL storage; 8-pin VSSOP; I²C-compatible but lacks TOUT push-pull output. | Lacks standalone thermostat functionality; requires host MCU to poll and assert external control signals. | Choose LM75BIMM/NOPB for cost-sensitive, non-critical monitoring where EEPROM persistence and direct TOUT drive are unnecessary. |
Compared with DS1731U+T&R, DS1631U+ offers superior accuracy but less predictable initialization, while LM75BIMM/NOPB reduces BOM cost at the expense of autonomous thermal response and long-term threshold retention.
Availability
DS1731U+T&R is available at Aetrix Electronics and suitable for network routers and switches, industrial motor control cabinets, and portable medical diagnostic devices requiring stable component supply across extended product lifecycles.
Supply support for DS1731U+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 and mixed-signal ICs for industrial, communications, and computing applications, emphasizing robustness, integration, and long-term manufacturability.
The DS1731U+T&R belongs to Maxim's high-accuracy digital temperature sensor family, engineered specifically for embedded thermal management where reliability, nonvolatile configuration, and minimal external components are mandatory.
FAQ
What is the guaranteed temperature accuracy specification for DS1731U+T&R?
The DS1731U+T&R guarantees ±1°C accuracy over the -10°C to +85°C range when powered at 3.0V to 5.5V. Outside this range - from -55°C to -10°C or +85°C to +125°C - the maximum error increases to ±2°C. This specification is measured under standard test conditions and reflects worst-case deviation from true temperature, not typical performance.
Does DS1731U+T&R automatically begin temperature conversions at power-up?
No, DS1731U+T&R does not auto-start conversions at power-up. Unlike the DS1631A, it remains in low-power idle state until explicitly commanded via the Start Convert T (0x51) instruction. This behavior ensures deterministic initialization and prevents unintended TOUT assertion during system boot sequences.
Can DS1731U+T&R operate on a shared I²C bus with other devices?
Yes, DS1731U+T&R supports true multidrop I²C operation. Its 7-bit slave address (1001 A2 A1 A0) is configured by hardware pins A0–A2, allowing up to eight DS1731U+T&R units - or combinations with DS1631/DS1631A - on a single 2-wire bus without address conflict or arbitration issues.
How is thermostat hysteresis implemented in DS1731U+T&R?
Hysteresis in DS1731U+T&R is implemented by independently programming upper (TH) and lower (TL) trip-point registers stored in NV EEPROM. The TOUT pin transitions high when temperature ≥ TH and remains high until temperature falls below TL - creating user-defined hysteresis width without external components or firmware intervention.
What package type and dimensions does DS1731U+T&R use?
DS1731U+T&R uses an 8-pin µSOP package (3mm × 3mm body, 0.5mm lead pitch). This compact surface-mount outline meets JEDEC MO-187 standards and is compatible with standard reflow profiles, including peak temperatures up to +220°C per IPC/JEDEC J-STD-020A.
DS1731U+T&R Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Sensor Type:
- Digital, Local
- Sensing Temperature - Local:
- -55°C ~ 125°C
- Sensing Temperature - Remote:
- -
- Output Type:
- I2C
- Voltage - Supply:
- 2.7V ~ 5.5V
- Resolution:
- 11 b
- Features:
- One-Shot, Output Switch, Programmable Limit, Programmable Resolution, Standby Mode
- Accuracy - Highest (Lowest):
- ±1°C (±2°C)
- Test Condition:
- 0°C ~ 70°C (-55°C ~ 125°C)
- Operating Temperature:
- -55°C ~ 125°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 8-uMAX/uSOP
DS1731U+T&R FAQ
1.How can I place an order for DS1731U+T&R through Aetrix?
Please submit a Request for Quotation (RFQ) for DS1731U+T&R on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for DS1731U+T&R reliable?
The price and inventory of DS1731U+T&R are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for DS1731U+T&R is usually 5 days.
3.What payment methods are accepted for DS1731U+T&R?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for DS1731U+T&R transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for DS1731U+T&R?
DS1731U+T&R orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your DS1731U+T&R order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for DS1731U+T&R?
For technical support, including DS1731U+T&R datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your DS1731U+T&R requirements.
6.How does Aetrix verify that DS1731U+T&R is sourced from the original manufacturer or authorized distributors?
All DS1731U+T&R products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that DS1731U+T&R meets industry standards.
7.What is the process for return or replacement of DS1731U+T&R?
All DS1731U+T&R units undergo pre-shipment inspection (PSI). If there is an issue with DS1731U+T&R, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The DS1731U+T&R part is unused and in its original packaging.
Return procedure for DS1731U+T&R:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
DS1731U+T&R Tags
-
MCP9700T-E/TT
Microchip Technology
-
MCP9700T-E/LT
Microchip Technology
-
MCP9701T-E/TT
Microchip Technology
-
MCP9701T-E/LT
Microchip Technology
-
TMP235A4DBZR
Texas Instruments
-
MCP9700AT-E/TT
Microchip Technology
-
MCP9700AT-E/LT
Microchip Technology
-
MCP9701AT-E/LT
Microchip Technology
-
MCP9701AT-E/TT
Microchip Technology
,TO-226_straightlead.jpg)
-
LM335Z
STMicroelectronics
-
TMP1075NDRLR
Texas Instruments
-
TMP1075DGKR
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
