LM81CIMT-3/NOPB

Product Overview

Category

The LM81CIMT-3/NOPB belongs to the category of integrated circuits (ICs).

Use

This IC is primarily used for temperature monitoring and fan control in electronic devices.

Characteristics

• Temperature Monitoring: The LM81CIMT-3/NOPB can accurately measure the temperature of its surroundings.
• Fan Control: It provides the capability to control the speed of cooling fans based on the measured temperature.
• Low Power Consumption: This IC operates with low power consumption, making it suitable for battery-powered devices.
• High Accuracy: The LM81CIMT-3/NOPB offers high accuracy in temperature measurement and fan control.
• Small Package Size: It comes in a compact package, allowing for easy integration into various electronic devices.

Package

The LM81CIMT-3/NOPB is available in a small outline integrated circuit (SOIC) package.

Essence

The essence of the LM81CIMT-3/NOPB lies in its ability to monitor temperature and control fans efficiently, ensuring optimal thermal management in electronic devices.

Packaging/Quantity

This IC is typically packaged in reels or tubes, with a quantity of 250 units per reel/tube.

Specifications

• Supply Voltage: 2.7V to 5.5V
• Temperature Measurement Range: -55°C to +125°C
• Temperature Resolution: 0.125°C
• Fan Control Output: PWM or DC voltage
• Communication Interface: I2C/SMBus compatible
• Operating Temperature Range: -40°C to +85°C

Detailed Pin Configuration

The LM81CIMT-3/NOPB has a total of 16 pins. Here is the detailed pin configuration:

1. VCC: Supply voltage input
2. GND: Ground reference
3. SDA: Serial data input/output for I2C communication
4. SCL: Serial clock input for I2C communication
5. ALERT#: Open-drain output for temperature alert
6. TACH1: Tachometer input for fan speed measurement
7. TACH2: Tachometer input for fan speed measurement
8. TACH3: Tachometer input for fan speed measurement
9. PWM1: Pulse-width modulation (PWM) output for fan control
10. PWM2: Pulse-width modulation (PWM) output for fan control
11. PWM3: Pulse-width modulation (PWM) output for fan control
12. VDDA: Analog supply voltage input
13. VSSA: Analog ground reference
14. VDDP: Power supply for internal digital circuitry
15. VSSP: Ground reference for internal digital circuitry
16. NC: No connection

Functional Features

The LM81CIMT-3/NOPB offers the following functional features:

1. Temperature Monitoring: Accurate measurement of ambient temperature.
2. Fan Control: Ability to adjust fan speed based on temperature readings.
3. Temperature Alert: Generates an alert signal when the temperature exceeds a predefined threshold.
4. Tachometer Inputs: Allows monitoring of fan speed through tachometer inputs.
5. PWM Outputs: Provides pulse-width modulation outputs for controlling fan speed.
6. I2C/SMBus Compatibility: Supports easy communication with other devices using the I2C or SMBus interface.

Advantages and Disadvantages

Advantages

• High accuracy in temperature measurement and fan control.
• Low power consumption, suitable for battery-powered devices.
• Compact package size for easy integration.
• Wide operating temperature range.
• Multiple tachometer inputs and PWM outputs for versatile fan control.

Disadvantages

• Limited temperature measurement range compared to some other ICs.
• Requires additional external components for fan control implementation.

Working Principles

The LM81CIMT-3/NOPB operates by measuring the voltage across a temperature sensor and converting it into a digital value. This digital value is then used to calculate the corresponding temperature. Based on the measured temperature, the IC adjusts the fan speed using the PWM outputs or DC voltage control. The temperature alert feature triggers an alert signal when the temperature exceeds a predefined threshold.

Detailed Application Field Plans

The LM81CIMT-3/NOPB finds applications in various electronic devices that require temperature monitoring and fan control. Some of the detailed application field plans include:

1. Personal Computers: Monitoring CPU temperature and controlling cooling fans.
2. Servers and Data Centers: Ensuring optimal thermal management for server racks and equipment.
3. Home Appliances: Temperature monitoring and fan control in refrigerators, ovens, and air conditioning systems.
4. Automotive Electronics: Managing temperature in engine control units (ECUs) and climate control systems.
5. Industrial Equipment: Thermal management in machinery, power supplies,