Overview
The ADM811SART-REEL7, produced by Analog Devices Inc., is a reliable voltage monitoring device designed for various voltage monitoring applications. It is part of the ADM811/ADM812 series, which are supervisory circuits intended to monitor and protect microprocessor systems from voltage anomalies. These devices are particularly useful in ensuring the stability and proper operation of microprocessors during power-up, power-down, and in the event of power supply interruptions or brownouts.
Key Specifications
| Parameter | Rating/Value | Notes |
|---|---|---|
| Terminal Voltage (VCC) | -0.3 V to +6 V | With respect to ground |
| All Other Inputs | -0.3 V to VCC + 0.3 V | |
| Input Current (VCC) | 20 mA | |
| Input Current (MR) | 20 mA | Manual Reset |
| Output Current (RESET) | 20 mA | |
| Power Dissipation (TA = 70°C) | 200 mW | Derate by 4 mW/°C above 70°C |
| Thermal Impedance (θJA) | 330°C/W | |
| Operating Temperature Range | -40°C to +85°C | |
| Storage Temperature Range | -65°C to +160°C | |
| Lead Temperature (Soldering, 10 sec) | 300°C | |
| ESD Rating | 3 kV |
Key Features
- Voltage Monitoring: The ADM811/ADM812 can monitor six different voltages, allowing for a 5% or 10% degradation of standard PSU voltages before a reset occurs. This includes monitoring of 2.5 V, 3 V, 3.3 V, and 5 V supply voltage levels.
- Reset Output: The ADM811 provides an active low reset output, while the ADM812 provides an active high reset output. The reset output remains valid during power-down, ensuring the microprocessor is held in a stable shutdown condition.
- Manual Reset Input: Equipped with a debounced manual reset input, which can be activated using an electrical switch or an input from another digital device. This feature is useful in noisy environments to prevent unwanted glitches.
- Power-On Reset Delay: The devices provide a power-on reset delay, allowing time for both the power supply and the microprocessor to stabilize after power-up. The reset output remains active for 240 ms (typical) after the supply recovers from a brownout or interruption.
Applications
- Microprocessor Systems: Ideal for monitoring and protecting microprocessors in various systems.
- Controllers and Intelligent Instruments: Suitable for use in control systems and intelligent instruments that require reliable voltage monitoring.
- Automotive Systems: Used in automotive applications where robust voltage monitoring is crucial.
- Safety Systems: Applied in safety-critical systems where reliable operation is essential.
- Portable Instruments: Used in portable instruments to ensure stable operation under varying power conditions).
Q & A
- What is the primary function of the ADM811/ADM812?
The primary function is to monitor supply voltages and provide a reset signal to the microprocessor in case of voltage anomalies or power supply interruptions.
- What types of reset outputs do the ADM811 and ADM812 provide?
The ADM811 provides an active low reset output, while the ADM812 provides an active high reset output).
- How does the manual reset input work?
The manual reset input is debounced and can be activated using an electrical switch or an input from another digital device, making it useful in noisy environments).
- What is the typical power-on reset delay of the ADM811/ADM812?
The typical power-on reset delay is 240 ms, allowing time for both the power supply and the microprocessor to stabilize after power-up).
- What are the operating temperature ranges for the ADM811/ADM812?
The operating temperature range is -40°C to +85°C).
- Can the ADM811/ADM812 be used in automotive systems?
Yes, these devices are suitable for use in automotive applications where robust voltage monitoring is crucial).
- What is the thermal impedance (θJA) of the ADM811/ADM812?
The thermal impedance (θJA) is 330°C/W).
- How many different voltages can the ADM811/ADM812 monitor?
The devices can monitor six different voltages, including 2.5 V, 3 V, 3.3 V, and 5 V supply voltage levels.
- What is the ESD rating of the ADM811/ADM812?
The ESD rating is 3 kV).
- Can the reset output remain valid during power-down?
Yes, the reset output remains valid during power-down, ensuring the microprocessor is held in a stable shutdown condition).
