My Inquiry
My Account
Texas Instruments LM86CIM-TI
- Part No.:
- LM86CIM-TI
- Manufacturer:
- Texas Instruments
- Category:
- Analog and Digital Output
- Package:
- -
- Datasheet:
-
LM86CIM-TI.pdf
- Description:
- SERIAL SWITCH/DIGITAL SENSOR, 11
- Quantity:
- Payment:
- Shipping:
Inventory:3,180
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM86CIM-TI from Texas Instruments (formerly National Semiconductor) is an 11-bit remote/local digital temperature sensor with SMBus 2.0 interface, ±0.75°C remote diode accuracy at 30°C–80°C, 0.125°C remote resolution, and dual open-drain alarm outputs (ALERT and T_CRIT_A). It measures local die temperature and remote IC junction temperature-e.g., Intel Pentium III thermal diode-enabling real-time thermal management in laptop CPU subsystems.
For engineers reviewing the LM86CIM-TI datasheet, LM86CIM-TI pinout, LM86CIM-TI application, or LM86CIM-TI equivalent, key selection criteria include SMBus 2.0 TIMEOUT support, factory-trimmed 1.008 non-ideality compensation for mobile Pentium III diodes, offset register programmability for alternate diodes, ±3.0°C local accuracy over 25°C–125°C, and SOIC-8/MSOP-8 package compatibility with ADM1032/MAX6657.
Technical Context
The LM86CIM-TI implements a delta-VBE sensing architecture with a 10-bit+sign ΔΣ ADC for local temperature and an 11-bit left-justified word format (0.125°C LSB) for remote diode readings. Its digital comparators independently monitor local and remote temperatures against user-programmable HIGH, LOW, and T_CRIT registers.
It supports three ALERT operating modes: standalone comparator (auto-clearing), interrupt flag (mask-bit controlled), and SMBus ARA protocol-compliant alert line sharing. The T_CRIT_A output features built-in hysteresis via the TH register and responds only to critical overtemperature events without software intervention.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Remote Temp Accuracy | ±0.75°C max at TA=30°C, TD=80°C - enables precise CPU thermal throttling without calibration |
| Local Temp Accuracy | ±3.0°C max over 25°C–125°C - sufficient for ambient board temperature monitoring |
| Remote Resolution | 0.125°C (11-bit) - allows fine-grained fan speed control and thermal margining |
| Supply Voltage | 3.0V–3.6V - compatible with standard 3.3V logic rails and avoids level-shifting |
| Quiescent Current | 0.8mA typical at 16Hz conversion rate - low power for always-on thermal supervision |
| SMBus Compatibility | Fully compliant with SMBus 2.0 including TIMEOUT reset - ensures robust communication in noisy server/laptop environments |
| Conversion Time | 31.25ms per full cycle (local + remote) - deterministic timing for predictable system response |
Pinout & Package
LM86CIM-TI is available in SOIC-8 package (M08A), with pins arranged in standard dual-inline configuration. Pin functions are electrically isolated and validated for SMBus 2.0 operation, diode bias current sourcing/sinking, and open-drain alarm signaling.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VDD | Positive supply input | Accepts 3.0–3.6V; powers internal bandgap reference, ADC, and SMBus interface |
| D+ | Diode current source | Drives 110–315µA into remote diode anode; optimized for 1.008 ideality factor |
| D− | Diode return sink | Sinks matched current from diode cathode; enables accurate ΔVBE measurement |
| T_CRIT_A | Critical temperature alarm | Open-drain, active-low output with hysteresis; triggers hardware shutdown on T_CRIT breach |
| GND | Power ground reference | Common return for VDD, D+, D−, and digital I/O; must be low-impedance for accuracy |
| ALERT | Configurable interrupt/alert | Open-drain output supporting comparator, interrupt, or SMBus ARA modes via CONFIG register |
| SMBData | SMBus bidirectional data | Open-drain, supports SMBus 2.0 protocols including TIMEOUT and ARA; requires external pull-up |
| SMBCLK | SMBus clock input | Asynchronous input up to 100kHz; no clock stretching supported |
Key Features
| Feature | Design Value |
|---|---|
| Factory-trimmed diode non-ideality compensation | Calibrated for 1.008 factor of mobile Pentium III thermal diode - eliminates software calibration for legacy x86 platforms |
| Programmable offset register | RTOLB/RTOHB registers allow accurate remote sensing of non-standard diodes (e.g., ASIC junctions) without firmware recalibration |
| Dual independent alarm outputs | T_CRIT_A provides hardware-level shutdown signal; ALERT supports flexible software-driven response - enables layered thermal protection |
| SMBus 2.0 TIMEOUT recovery | Holding SMBData/SMBCLK low >25ms resets state machine - prevents bus lockup in noisy embedded systems |
| Diode fault detection | Auto-detects D+ short-to-VDD/floating (loads RTHB=+127°C) or short-to-GND (loads RTHB=−128°C) - distinguishes faults from valid 0°C readings |
Applications
| Laptop CPU Thermal Monitoring | Server Blade Temperature Supervision |
|---|---|
|
Use Scenario: Real-time tracking of Intel Pentium III processor die temperature using its integrated thermal diode. IC Role / Device Role / Timing Role: Remote diode sensor with factory-trimmed 1.008 ideality compensation; performs 31.25ms conversions synchronized to SMBus polling. Use Value: Enables dynamic fan control and OS-level thermal throttling with ±0.75°C accuracy at critical operating points. |
Use Scenario: Simultaneous monitoring of multiple hotspots (CPU, VRM, memory) across a dense 1U server blade. IC Role / Device Role / Timing Role: Local + remote sensor with dual SMBus-compatible alarm outputs; shares ALERT line via ARA protocol. Use Value: Reduces BOM count by consolidating thermal sensing per module while maintaining independent T_CRIT thresholds. |
| Industrial PC Fan Control | Embedded Network Appliance Thermal Safety |
|
Use Scenario: Closed-loop fan speed regulation based on measured SoC junction temperature in fanless-to-fan-cooled transition zones. IC Role / Device Role / Timing Role: Remote diode sensor with programmable offset register; interfaces via SMBus to ARM-based controller. Use Value: Eliminates need for external calibration when adapting to custom ASIC thermal diodes, reducing qualification time. |
Use Scenario: Hardware-enforced thermal shutdown path independent of host firmware in firewall/routing appliances. IC Role / Device Role / Timing Role: T_CRIT_A output directly drives power supply enable line; activates within 31.25ms of overtemperature event. Use Value: Guarantees fail-safe shutdown even during host CPU lockup or firmware crash. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar remote/local temperature sensing applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ADM1032ARQZ | Pin- and register-compatible; identical SMBus interface and alarm behavior; ±1.0°C remote accuracy over wider range (0°C–125°C) | Higher remote accuracy tolerance at extremes; lacks dedicated T_CRIT_A output - uses single ALERT with configurable priority | Preferred where broader remote temperature range validation is required and dual-alarm hardware separation is not mandatory |
| MAX6657AESA+ | Pin-compatible; same 11-bit remote resolution; ±1.5°C remote accuracy at 85°C; no factory diode ideality trim | Requires software calibration for Pentium III diodes; supports 12-bit local mode (not used in LM86CIM-TI default config) | Selected when cost sensitivity outweighs need for out-of-box Pentium III compatibility and higher remote accuracy |
Compared with ADM1032ARQZ and MAX6657AESA+, the LM86CIM-TI delivers superior remote diode accuracy (±0.75°C) specifically for mobile Pentium III, includes a dedicated hardware T_CRIT_A output for fail-safe shutdown, and integrates factory-trimmed ideality compensation-reducing design validation effort in x86 client platforms.
Availability
LM86CIM-TI is available at Aetrix Electronics and suitable for laptop thermal management, server blade supervision, and industrial PC fan control requiring stable component supply and long-term lifecycle support.
Supply support for LM86CIM-TI 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 acquired National Semiconductor in 2011 and maintains full technical and supply chain responsibility for legacy precision analog products including the LM86 series.
The LM86CIM-TI belongs to TI's thermal sensing portfolio designed for high-accuracy, SMBus-connected temperature monitoring in computing and embedded systems where reliability and diode-specific calibration matter.
FAQ
What is the remote temperature accuracy specification for LM86CIM-TI at typical CPU operating conditions?
The LM86CIM-TI achieves ±0.75°C maximum remote diode temperature accuracy when ambient temperature (TA) is 30°C and remote diode junction temperature (TD) is 80°C-matching typical mobile Pentium III CPU load conditions. This accuracy is factory-trimmed for the 1.008 non-ideality factor of that specific thermal diode. At other ranges (e.g., TA=0°C–85°C, TD=25°C–125°C), accuracy degrades to ±3.0°C max. The LM86CIM-TI datasheet specifies these limits under defined test conditions with proper PCB layout and decoupling.
Does LM86CIM-TI support SMBus 2.0 TIMEOUT functionality, and how is it implemented?
Yes, LM86CIM-TI fully supports SMBus 2.0 TIMEOUT. If the SMBData or SMBCLK line is held low for longer than tTIMEOUT (25–35ms), the device resets its internal SMBus state machine and places SMBData and SMBCLK pins in high-impedance mode. This recovers communication without requiring power cycling. The LM86CIM-TI does not stretch the clock and relies solely on this TIMEOUT mechanism for bus error recovery-critical in electrically noisy laptop or server chassis environments.
How does the LM86CIM-TI handle remote diode faults, and what diagnostic indicators are provided?
The LM86CIM-TI detects two primary remote diode faults: D+ shorted to VDD or floating (sets RTHB=+127°C, RTLB=0, OPEN bit=1), and D+ shorted to GND or D− (sets RTHB=−128°C, OPEN bit=0). These codes are unambiguous-+127°C and −128°C cannot occur as valid measurements-so firmware can distinguish faults from actual temperatures. The OPEN bit in the Status Register (02h, bit D2) is set only for open-circuit conditions, and neither OPEN nor fault codes trigger ALERT unless corresponding limit registers are configured below those values.
Can LM86CIM-TI measure temperatures of non-Intel thermal diodes, and what configuration is required?
Yes, LM86CIM-TI supports non-Intel diodes via its programmable offset registers (RTOLB and RTOHB). These 8-bit registers allow adding or subtracting up to ±127°C in 1°C steps to compensate for diode non-ideality factors differing from the factory-trimmed 1.008 value. For example, AMD or custom ASIC diodes with ideality factors of 1.002 or 1.015 require offset tuning-documented in TI's LM86 application notes. The LM86CIM-TI retains full 0.125°C resolution after offset application, and offset values persist across power cycles if stored in nonvolatile configuration.
What is the functional difference between ALERT and T_CRIT_A outputs on LM86CIM-TI?
ALERT is a multifunction, software-configurable open-drain output supporting three modes: standalone comparator (auto-clearing), interrupt flag (mask-bit gated), or SMBus ARA alert line participant. T_CRIT_A is a dedicated, hardware-only open-drain output that activates *only* when any temperature exceeds its respective T_CRIT register-and remains asserted until temperature falls below T_CRIT minus hysteresis (TH register value). Unlike ALERT, T_CRIT_A cannot be masked or reconfigured; it provides a deterministic, fail-safe hardware shutdown path independent of firmware state, making it essential for safety-critical thermal protection in the LM86CIM-TI.
LM86CIM-TI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- *
- Package/Case:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Sensor Type:
- -
- Sensing Temperature - Local:
- -
- Sensing Temperature - Remote:
- -
- Output Type:
- -
- Voltage - Supply:
- -
- Resolution:
- -
- Features:
- -
- Accuracy - Highest (Lowest):
- -
- Test Condition:
- -
- Operating Temperature:
- -
- Mounting Type:
- -
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- -
LM86CIM-TI FAQ
1.How can I place an order for LM86CIM-TI through Aetrix?
Please submit a Request for Quotation (RFQ) for LM86CIM-TI 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 LM86CIM-TI reliable?
The price and inventory of LM86CIM-TI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM86CIM-TI is usually 5 days.
3.What payment methods are accepted for LM86CIM-TI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM86CIM-TI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM86CIM-TI?
LM86CIM-TI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM86CIM-TI 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 LM86CIM-TI?
For technical support, including LM86CIM-TI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM86CIM-TI requirements.
6.How does Aetrix verify that LM86CIM-TI is sourced from the original manufacturer or authorized distributors?
All LM86CIM-TI 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 LM86CIM-TI meets industry standards.
7.What is the process for return or replacement of LM86CIM-TI?
All LM86CIM-TI units undergo pre-shipment inspection (PSI). If there is an issue with LM86CIM-TI, 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 LM86CIM-TI part is unused and in its original packaging.
Return procedure for LM86CIM-TI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM86CIM-TI 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…
