Texas Instruments LM96000CIMTX

Overview

LM96000CIMTX from Texas Instruments is a hardware monitor IC with integrated SMBus 2.0–compliant fan control, measuring five motherboard power rails (VCCP, 2.5V, 3.3VSBY, 5.0V, 12V), two remote thermal diodes, and its own die temperature. It delivers ±2% full-scale voltage accuracy, ±3°C remote temperature accuracy (0°C to +125°C), and 1°C digital resolution for thermal management in desktop PC motherboards.

For engineers reviewing the LM96000CIMTX datasheet, LM96000CIMTX pinout, LM96000CIMTX application, or LM96000CIMTX equivalent, this device supports autonomous PWM fan speed regulation across three zones, four tachometer inputs, five VID lines, and noise-filtered temperature readings - critical for stable thermal control in microprocessor-based embedded systems.

Technical Context

The LM96000CIMTX integrates an 8-bit ΣΔ ADC with internal scaling resistors for direct monitoring of five analog voltage inputs and dual remote diode interfaces using current-source/sink architecture. Its SMBus 2.0 interface operates at 10–100 kHz with programmable addressing via PWM3/Address Enable and TACH4 pins.

Fan control logic uses three independent PWM outputs (10 Hz–30 kHz range, 0–100% duty cycle, 8-bit resolution) assigned to three thermal zones, each configurable with spin-up delay (100–4000 ms), absolute temperature limits, hysteresis, and spike-smoothing filters. All registers are accessible via 7-bit SMBus address (default 0x2E).

Key Specifications

Pinout & Package

LM96000CIMTX is housed in a 24-pin Thin Shrink Small Outline Package (TSSOP) with exposed pad (no thermal pad connection required per datasheet). Pin 1 is marked by a dot; top-view orientation follows JEDEC MO-153.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar hardware monitoring applications.

Compared with LM96000CIMTX, LM96163CIMT offers improved thermal accuracy and bus protocol but demands firmware updates, while ADM1027ARUZ provides watchdog capability at the cost of VID support and register-level incompatibility - both require PCB and software revisions.

Availability

LM96000CIMTX is available at Aetrix Electronics and suitable for desktop PC motherboard manufacturing, microprocessor-based network equipment, and embedded industrial controller applications requiring stable component supply and long-term lifecycle support.

Supply support for LM96000CIMTX 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, embedded processing, and system-on-chip solutions for industrial, automotive, and computing markets.

The LM96000CIMTX belongs to TI's hardware monitor product line, designed specifically for autonomous thermal and power supervision in x86-based desktop and embedded computing platforms - emphasizing SMBus integration, multi-rail monitoring, and fan control without host processor overhead.

FAQ

What is the operating temperature range of the LM96000CIMTX?

The LM96000CIMTX operates from 0°C to +85°C ambient temperature. Its remote diode sensing circuitry supports temperature measurements from 0°C to +125°C, enabling accurate thermal monitoring of processors and other hot components. The on-die temperature sensor matches this operational range, and all specifications - including voltage accuracy and PWM timing - are guaranteed within these limits. LM96000CIMTX must be mounted on a PCB with adequate copper pour to maintain junction temperature within safe limits.

Does the LM96000CIMTX require external resistors for voltage monitoring?

No, the LM96000CIMTX includes internal precision scaling resistors for all five monitored voltage inputs (VCCP_IN, 2.5V, 3.3VSBY, 5V, and 12V), eliminating the need for external resistor dividers. Each input is internally configured for optimal full-scale range - for example, the 12V input is scaled to match the ADC's 0–255 code span at nominal 12V. External bypass capacitors (0.1 µF + 100 pF on 3.3V, 10 µF bulk) are required, but no scaling resistors are needed. LM96000CIMTX simplifies design and improves measurement consistency across production units.

How does the LM96000CIMTX handle remote thermal diode inaccuracies?

The LM96000CIMTX achieves ±3°C remote temperature accuracy when used with Intel Pentium 4 90nm processors or thermal diodes exhibiting 1.011 non-ideality factor and 3.33Ω series resistance. For discrete diodes like the MMBT3904, calibration offsets may apply - the datasheet notes typical error shifts but does not specify compensation algorithms. LM96000CIMTX does not perform automatic non-ideality correction; system designers must validate diode selection and layout per TI's application notes. LM96000CIMTX relies on proper external diode placement and trace routing to minimize parasitic effects.

Can multiple LM96000CIMTX devices share the same SMBus?

Yes, up to three LM96000CIMTX devices can coexist on a single SMBus segment using address selection mode. By pulling PWM3/AddressEnable low and configuring TACH4 (Address Select) to logic high or low, the device adopts SMBus addresses 0x2C or 0x2D; the default address is 0x2E. Address latching occurs during the first valid SMBus transaction matching the leading five bits (01011b). LM96000CIMTX supports this multi-drop configuration without additional level-shifting or arbitration hardware - ideal for multi-processor or multi-zone systems.

What fan control features does the LM96000CIMTX support beyond basic PWM?

The LM96000CIMTX supports programmable spin-up delay (100–4000 ms), zone-specific temperature hysteresis, absolute trip limits (e.g., 64°C), and spike-smoothing filters with adjustable time constants (0.35–0.8 sec). It assigns each of three PWM outputs to one of three thermal zones, allowing independent control logic - for example, PWM2 and PWM3 can both respond to Zone 2 temperature. LM96000CIMTX also provides tachometer validation: if fan RPM falls below programmed minimums, it triggers alarm flags in interrupt registers. LM96000CIMTX executes all logic autonomously without host polling.