Overview
The LM45CIM3X/NOPB from Texas Instruments is a precision integrated-circuit temperature sensor designed to provide accurate and reliable temperature measurements. This device is calibrated directly in degrees Celsius (centigrade) and features a linear output voltage that is proportional to the temperature, with a scale factor of 10 mV/°C. The LM45 does not require external calibration or trimming, ensuring high accuracy and ease of use. It operates over a wide temperature range of −20°C to +100°C and is suitable for various applications requiring precise temperature monitoring.
Key Specifications
| Parameter | Conditions | Typical Limit | Max Limit |
|---|---|---|---|
| Accuracy | TA = +25°C | ±2.0°C | ±3.0°C |
| Accuracy | TA = TMIN to TMAX | ±3.0°C | ±4.0°C |
| Nonlinearity | TMIN ≤ TA ≤ TMAX | ±0.8°C | ±0.8°C |
| Sensor Gain (Average Slope) | TMIN ≤ TA ≤ TMAX | +9.7 mV/°C to +10.3 mV/°C | |
| Load Regulation | 0 ≤ IL ≤ +1 mA | ±35 mV/mA | |
| Line Regulation | +4.0V ≤ +VS ≤ +10V | ±0.80 mV/V | |
| Quiescent Current | +4.0V ≤ +VS ≤ +10V, +25°C | 120 μA | 160 μA |
| Supply Voltage Range | +4.0V to +10V | ||
| Operating Temperature Range | −20°C to +100°C | ||
| Output Impedance | For 1 mA Load | 20Ω | |
| Self-Heating | In Still Air | < 0.2°C |
Key Features
- Linear Output Voltage: The LM45 provides a linear output voltage proportional to the temperature, with a scale factor of 10 mV/°C.
- High Accuracy: Guaranteed accuracy of ±2°C at room temperature and ±3°C over the full −20°C to +100°C temperature range.
- Low Self-Heating: Less than 0.2°C self-heating in still air, ensuring minimal impact on the measured temperature.
- Low Power Consumption: Draws only 120 μA from the supply, making it suitable for battery-powered applications.
- Wide Operating Range: Operates from a supply voltage of +4.0V to +10V and over a temperature range of −20°C to +100°C.
- Easy Interfacing: Low output impedance and linear output make it easy to interface with readout or control circuitry.
- Compact Package: Available in a small SOT-23 package, making it ideal for space-constrained applications.
Applications
- Battery Management: Suitable for monitoring battery temperatures in various battery management systems.
- Fax Machines and Printers: Used in office equipment to monitor and control temperature.
- Portable Medical Instruments: Ideal for temperature monitoring in medical devices due to its high accuracy and reliability.
- HVAC Systems: Used in heating, ventilation, and air conditioning systems for precise temperature control.
- Power Supply Modules: Monitors temperature in power supply units to ensure safe and efficient operation.
- Disk Drives and Computers: Used in electronic devices to monitor and manage internal temperatures.
- Automotive Systems: Suitable for various automotive applications requiring precise temperature monitoring.
Q & A
- What is the temperature range of the LM45CIM3X/NOPB?
The LM45CIM3X/NOPB operates over a temperature range of −20°C to +100°C.
- What is the accuracy of the LM45CIM3X/NOPB at room temperature?
The accuracy at room temperature is ±2°C.
- What is the scale factor of the LM45CIM3X/NOPB?
The scale factor is 10 mV/°C.
- What is the typical quiescent current of the LM45CIM3X/NOPB?
The typical quiescent current is 120 μA.
- What is the supply voltage range for the LM45CIM3X/NOPB?
The supply voltage range is from +4.0V to +10V.
- What is the output impedance of the LM45CIM3X/NOPB for a 1 mA load?
The output impedance is 20Ω for a 1 mA load).
- How much self-heating does the LM45CIM3X/NOPB experience in still air?
The self-heating is less than 0.2°C in still air).
- In what package is the LM45CIM3X/NOPB available?
The LM45CIM3X/NOPB is available in a SOT-23 (DBZ) package with 3 pins).
- What are some common applications of the LM45CIM3X/NOPB?
Common applications include battery management, fax machines, printers, portable medical instruments, HVAC systems, power supply modules, disk drives, computers, and automotive systems).
- How can the LM45CIM3X/NOPB be mounted for temperature measurement?
The LM45CIM3X/NOPB can be glued or cemented to a surface, mounted inside a sealed-end metal tube, or attached to a printed circuit board to measure temperature accurately).
