Overview
The LM809M3-2.63/NOPB is a microprocessor supervisory circuit produced by Texas Instruments. This component is designed to monitor the power supplies in microprocessor and digital systems, providing a reset signal during power-up, power-down, and brown-out conditions. The LM809 series is a superior upgrade to the MAX809 and offers precision monitoring of supply voltages with various threshold options.
The LM809M3-2.63/NOPB specifically has a reset threshold of 2.63 V, making it suitable for monitoring 3-V supply voltages. It features an active-low RESET output and ensures the reset signal remains asserted for a minimum of 140 ms after the VCC rises above the threshold.
Key Specifications
| Parameter | Min | Typical | Max | Unit |
|---|---|---|---|---|
| Reset Threshold (VTH) | 2.59 | 2.63 | 2.66 | V |
| Reset Active Timeout Period | 140 | 240 | 560 | ms |
| VCC to Reset Delay | 20 | - | - | µs |
| RESET Output Voltage Low (LM809) | 0.3 | - | - | V |
| Supply Current | - | 15 | - | µA |
| Operating Temperature Range | -40 | - | 105 | °C |
| Package Type | - | SOT-23 | - | - |
| Body Size (Nom) | - | 2.92 mm × 1.30 mm | - | - |
Key Features
- Precision monitoring of supply voltages with threshold options of 2.63 V, 2.93 V, 3.08 V, 4.38 V, and 4.63 V.
- Active-low RESET output for LM809 and active-high RESET output for LM810.
- Minimum power-on reset pulse width of 140 ms and typical of 240 ms.
- Low supply current of 15 µA, making it ideal for portable equipment.
- Power supply transient immunity.
- Fully specified over temperature range of -40°C to 105°C.
Applications
- Microprocessor Systems
- Computers
- Controllers
- Intelligent Instruments
- Portable/Battery-Powered Equipment
- Automotive Systems
- Factory Automation
- Building Automation
- Programmable Logic Control
- Renewable Energy Systems
Q & A
- What is the primary function of the LM809M3-2.63/NOPB?
The primary function is to monitor the power supply voltage and provide a reset signal to the microprocessor during power-up, power-down, and brown-out conditions.
- What is the reset threshold voltage for the LM809M3-2.63/NOPB?
The reset threshold voltage is 2.63 V.
- What is the typical reset active timeout period for the LM809?
The typical reset active timeout period is 240 ms.
- What is the supply current of the LM809M3-2.63/NOPB?
The supply current is typically 15 µA.
- What package type is the LM809M3-2.63/NOPB available in?
The component is available in a SOT-23 package.
- What are the operating temperature ranges for the LM809M3-2.63/NOPB?
The operating temperature range is from -40°C to 105°C.
- How does the LM809M3-2.63/NOPB handle power supply transients?
The component has built-in power supply transient immunity.
- Can the LM809M3-2.63/NOPB be used in automotive systems?
- How does the LM809M3-2.63/NOPB interface with microprocessors having bidirectional reset pins?
A 4.7-kΩ resistor can be used to connect the LM809 RESET output to the microprocessor reset pin to ensure correct output.
- What are some common applications of the LM809M3-2.63/NOPB?
Common applications include microprocessor systems, computers, controllers, and portable/battery-powered equipment.
