## Overview of ADM1815-R22ART-RL The **ADM1815-R22ART-RL** is a high-reliability microprocessor supervisory circuit manufactured by **Analog Devices**. Its primary function is to monitor power supply voltages in microprocessor systems and provide a reset signal to the processor during power-up, power-down, and brownout conditions. --- ### Key Technical Specifications | Feature | Specification | |:---|:---| | **Threshold Voltage ($V_{TH}$)** | 2.18V (Nominal) | | **Output Stage** | Push-Pull (Active Low) | | **Reset Timeout Period** | 150 ms (Minimum) | | **Operating Voltage Range** | 1.0V to 5.5V | | **Supply Current** | 12 $\mu$A (Typical) | | **Package Type** | SOT-23 (3-lead) | | **Operating Temperature** | -40°C to +105°C | --- ### Core Components and Functionality 1. **Precision Voltage Reference:** Internal circuitry maintains a highly accurate reference to compare against the $V_{CC}$ pin. The "R22" suffix specifically indicates a 2.18V threshold. 2. **Comparator Circuitry:** The device continuously monitors the supply voltage. If the voltage drops below the 2.18V threshold, the comparator triggers the reset logic. 3. **Reset Timer:** Once the supply voltage rises back above the threshold, the device does not release the reset immediately. It holds the `RESET` signal low for approximately **150ms** to ensure the power supply has stabilized. 4. **Push-Pull Output:** Unlike "Open Drain" variants (like the ADM1810), the ADM1815 features a **Push-Pull** output. This means it can drive the output line high or low without requiring an external pull-up resistor. --- ### Pin Configuration | Pin Number | Name | Description | |:---:|:---|:---| | 1 | `RESET` | Active-low output signal. Remains low while $V_{CC}$ is below threshold. | | 2 | $V_{CC}$ | Supply voltage input and monitored voltage. | | 3 | GND | Ground reference. | --- ### Application Usage This component is typically used in battery-powered equipment, automotive systems, and industrial controllers where system stability is critical. ```c // Pseudo-code representation of ADM1815 logic if (Vcc < 2.18V) { Set_Reset_Pin(LOW); } else { Wait(150ms); Set_Reset_Pin(HIGH); } ```