My Inquiry
My Account
Texas Instruments LM95231BIMMX-1/NOPB
- Part No.:
- LM95231BIMMX-1/NOPB
- Manufacturer:
- Texas Instruments
- Category:
- Analog and Digital Output
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
LM95231BIMMX-1/NOPB.pdf
- Description:
- SENSOR DIGITAL 0C-85C 8VSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:4,444
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM95231BIMMX-1/NOPB from Texas Instruments is a precision dual remote diode temperature sensor IC with SMBus 2.0 interface and TruTherm™ technology, designed for accurate die temperature monitoring of Intel Pentium 4 (90nm) processors and discrete MMBT3904 transistors. It delivers ±0.75°C remote accuracy, 13-bit resolution (0.03125°C LSB) with digital filtering, and operates from 3.0V to 3.6V supply.
For engineers reviewing the LM95231BIMMX-1/NOPB datasheet, LM95231BIMMX-1/NOPB pinout, LM95231BIMMX-1/NOPB application, or LM95231BIMMX-1/NOPB equivalent, this device supports three-zone thermal sensing (local + two remote diodes), programmable non-ideality selection, SMBus-compatible communication, and fault detection for open/shorted diode connections in high-reliability computing systems.
Technical Context
The LM95231BIMMX-1/NOPB implements a sigma-delta ADC with ΔVBE sensing architecture optimized for thermal diode inputs. Its analog front-end includes TruTherm technology to correct non-ideality spread in 90nm-process processor diodes and integrated analog filtering to reduce external capacitor dependency.
Digital filtering (13-bit resolution, 0.03125°C LSB) and programmable conversion rate (1–10 Hz) enable trade-offs between noise immunity and power consumption (402 µA typical quiescent current). The device supports register-based selection between Pentium 4 90nm and MMBT3904 diode models, with TruTherm mode enabled only for the former.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Remote Temp Accuracy | ±0.75°C max (Intel 90nm thermal diode, TA = +20°C to +40°C) |
| Local Temp Accuracy | ±3.0°C max (TA = 0°C to +85°C, excludes self-heating) |
| Supply Voltage Range | 3.0 V to 3.6 V - requires 0.1 µF + 100 pF bypass at VDD |
| Resolution (Remote, filtered) | 13-bit unsigned or 12-bit plus sign - resolves temperatures >127°C with 0.03125°C LSB |
| Resolution (Local) | 9-bit plus sign - fixed 0.25°C LSB, clamped at +127.875°C |
| SMBus Compatibility | Fully compliant with SMBus 2.0 - supports TIMEOUT reset, no clock stretching |
| Operating Temp Range | 0°C to +125°C junction - rated for industrial/computing environments |
Pinout & Package
LM95231BIMMX-1/NOPB is housed in an 8-pin VSSOP package (2.3 mm × 2.0 mm, 0.5 mm pitch), optimized for space-constrained PCB layouts near CPU or GPU thermal sources.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| D1+ | Diode current source | Drives current into anode of first remote thermal diode (e.g., Pentium 4 die); no external capacitor required but 100 pF improves noise immunity |
| D1− | Diode return current sink | Sinks current from cathode of first remote diode; forms differential pair with D1+ for ΔVBE measurement |
| D2+ | Diode current source | Drives second remote diode (e.g., MMBT3904); independently configurable for different non-ideality model |
| D2− | Diode return current sink | Sinks current from second remote diode cathode; enables simultaneous dual-zone monitoring |
| GND | Power supply ground | Low-noise system ground reference; must be routed separately from noisy digital/power grounds |
| VDD | Positive supply input | 3.0–3.6 V supply; bypassing with 0.1 µF + 100 pF is mandatory for stable operation |
| SMBDAT | SMBus bidirectional data line | Open-drain output - requires external pull-up resistor (≤82 kΩ at 3.0 V) for proper logic high |
| SMBCLK | SMBus clock input | Asynchronous clock input (10–100 kHz); no internal pull-up - external pull-up required |
Key Features
| Feature | Design Value |
|---|---|
| TruTherm™ technology | Reduces non-ideality spread in 90nm Intel processor thermal diodes, enabling ±0.75°C accuracy without per-unit calibration |
| Dual independent remote channels | Simultaneously monitors two distinct thermal zones (e.g., CPU core + GPU or VRM) with separate diode model selection |
| Programmable digital filtering | Enables 13-bit resolution (0.03125°C LSB) for enhanced noise rejection on long PCB traces or cables |
| Diode fault detection | Flags D1+/D2+ short-to-rail or floating conditions via status register bits RD1M/RD2M, preventing erroneous thermal shutdowns |
| 1-shot conversion control | Allows host microcontroller to trigger single temperature reads on demand, minimizing background power draw during idle periods |
Applications
| Laptop Thermal Management | Server Blade Monitoring |
|---|---|
Use Scenario: Real-time CPU and GPU die temperature tracking in thin-profile laptops with limited airflow and high-power-density SoCs. IC Role / Device Role / Timing Role: Dual-channel remote diode sensor providing synchronized local + two remote readings via SMBus for dynamic fan speed and throttling control. Use Value: Enables precise thermal margining using ±0.75°C remote accuracy and 0.03125°C resolution, reducing unnecessary throttling while maintaining safety limits. |
Use Scenario: Multi-node thermal supervision in 1U server blades where each node hosts CPU, memory controller, and VRM with discrete thermal diodes. IC Role / Device Role / Timing Role: Centralized temperature acquisition IC interfacing with baseboard management controller (BMC) over SMBus for consolidated thermal telemetry. Use Value: Dual independent diode inputs eliminate need for multiple sensors per node, simplifying BOM and layout while supporting both Intel 90nm and discrete transistor diodes. |
| Workstation Graphics Cooling | Industrial Embedded Control |
Use Scenario: High-resolution thermal feedback for liquid-cooled GPU modules in professional workstations requiring sub-degree stability. IC Role / Device Role / Timing Role: Precision remote sensor measuring GPU die temperature and local board ambient, feeding closed-loop pump/fan control algorithm. Use Value: 13-bit filtered resolution (0.03125°C) enables fine-grained thermal response, improving cooling efficiency and acoustic performance under variable loads. |
Use Scenario: Temperature supervision in ruggedized embedded controllers deployed in factory automation cabinets with wide ambient swings (−20°C to +70°C). IC Role / Device Role / Timing Role: Local + remote diode sensor verifying thermal integrity of FPGA or DSP die and power stage MOSFETs under continuous operation. Use Value: Robust fault detection (open/short diode) and −40°C to +125°C operating range ensure reliable thermal protection without false alarms in harsh environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual remote diode temperature sensing applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM95235CIMMX-1/NOPB | Higher accuracy (±0.5°C remote), extended remote range (−64°C to +150°C), same VSSOP-8 package and SMBus interface | Targeted at high-end servers and telecom infrastructure requiring tighter thermal margins | Select when ±0.5°C remote accuracy and wider temperature range are critical; pin-compatible but requires updated firmware for extended register map |
| MAX6642AESA+ | Lower quiescent current (250 µA), 12-bit resolution (0.0625°C LSB), supports only single remote diode + local | Suitable for cost-sensitive, low-power embedded designs with single-processor thermal monitoring | Choose for simpler systems needing only one remote channel and lower power; not pin- or register-compatible with LM95231BIMMX-1/NOPB |
Compared with LM95231BIMMX-1/NOPB, LM95235CIMMX-1/NOPB offers higher accuracy and broader range for premium thermal control, while MAX6642AESA+ trades dual-channel capability and resolution for lower power and cost in single-diode applications.
Availability
LM95231BIMMX-1/NOPB is available at Aetrix Electronics and suitable for laptop thermal management, server blade monitoring, workstation graphics cooling, and industrial embedded control requiring stable component supply across production lifecycles.
Supply support for LM95231BIMMX-1/NOPB 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
Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision sensing and power management ICs.
The LM95231 product line was developed specifically for high-accuracy, multi-zone thermal monitoring in x86 computing platforms-addressing the growing need for reliable die temperature feedback in 90nm and smaller process nodes.
FAQ
What is the remote temperature accuracy specification for LM95231BIMMX-1/NOPB when used with an Intel Pentium 4 90nm processor?
The LM95231BIMMX-1/NOPB achieves ±0.75°C maximum remote temperature accuracy when configured for Intel Pentium 4 90nm thermal diode operation (TruTherm mode enabled), tested over +20°C to +40°C ambient and +45°C to +85°C diode junction temperature. This accuracy is ensured only when the Remote Diode Model Select register is set to the Pentium 4 90nm option and TruTherm mode is active.
Does LM95231BIMMX-1/NOPB support both signed and unsigned temperature data formats for remote readings?
Yes, LM95231BIMMX-1/NOPB supports both signed and unsigned formats for remote temperature data. With digital filtering disabled, it outputs 11-bit unsigned or 10-bit plus sign data (0.125°C LSB). With filtering enabled, it provides 13-bit unsigned or 12-bit plus sign data (0.03125°C LSB), allowing resolution of temperatures above 127°C in unsigned mode.
How does the diode fault detection function in LM95231BIMMX-1/NOPB indicate a failed remote connection?
When LM95231BIMMX-1/NOPB detects a fault-such as D1+ shorted to VDD, GND, or D1−, or D1+ floating-it reports −128.000°C (signed format) or +255.875°C (unsigned format) in the corresponding remote temperature register and sets the RD1M bit (bit D1) in the Status Register (02h). Identical behavior applies to D2+ faults with RD2M (bit D0).
Can LM95231BIMMX-1/NOPB measure temperature using a standard 2N3904 transistor as the remote diode?
Yes, LM95231BIMMX-1/NOPB explicitly supports MMBT3904 (equivalent to 2N3904) as a remote thermal diode. The device must be configured with Remote Diode Model Select set to "2N3904" and TruTherm mode disabled. Accuracy in this configuration is ±1.25°C max under specified test conditions, and enabling TruTherm mode with this diode may produce invalid readings.
What is the SMBus address of LM95231BIMMX-1/NOPB and how is it determined?
The SMBus slave address of LM95231BIMMX-1/NOPB is fixed at 0x4C (7-bit address), derived from its part number suffix "-1". Per TI's addressing scheme, LM95231BIMMX-1/NOPB maps to A6–A0 = 0011001, yielding 0x4C. This address is hardwired and cannot be modified via software or hardware pins, ensuring predictable bus enumeration in multi-sensor systems.
LM95231BIMMX-1/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- TruTherm™
- Package/Case:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Sensor Type:
- Digital, Local/Remote
- Sensing Temperature - Local:
- 0°C ~ 85°C
- Sensing Temperature - Remote:
- 0°C ~ 85°C
- Output Type:
- SMBus
- Voltage - Supply:
- 3V ~ 3.6V
- Resolution:
- 9 b (Local), 12 b (Remote)
- Features:
- One-Shot, Programmable Resolution, Shutdown Mode, Standby Mode
- Accuracy - Highest (Lowest):
- ±3°C
- Test Condition:
- 0°C ~ 85°C
- Operating Temperature:
- 0°C ~ 125°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 8-VSSOP
LM95231BIMMX-1/NOPB FAQ
1.How can I place an order for LM95231BIMMX-1/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM95231BIMMX-1/NOPB 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 LM95231BIMMX-1/NOPB reliable?
The price and inventory of LM95231BIMMX-1/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM95231BIMMX-1/NOPB is usually 5 days.
3.What payment methods are accepted for LM95231BIMMX-1/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM95231BIMMX-1/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM95231BIMMX-1/NOPB?
LM95231BIMMX-1/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM95231BIMMX-1/NOPB 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 LM95231BIMMX-1/NOPB?
For technical support, including LM95231BIMMX-1/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM95231BIMMX-1/NOPB requirements.
6.How does Aetrix verify that LM95231BIMMX-1/NOPB is sourced from the original manufacturer or authorized distributors?
All LM95231BIMMX-1/NOPB 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 LM95231BIMMX-1/NOPB meets industry standards.
7.What is the process for return or replacement of LM95231BIMMX-1/NOPB?
All LM95231BIMMX-1/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM95231BIMMX-1/NOPB, 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 LM95231BIMMX-1/NOPB part is unused and in its original packaging.
Return procedure for LM95231BIMMX-1/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM95231BIMMX-1/NOPB 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…
