The **ADM1815-R22AKSZ-R7** is a high-performance voltage monitoring device manufactured by **Analog Devices**. It belongs to the microprocessor supervisory circuit family, designed to monitor power supply voltages and provide a reset signal to a system processor when the voltage falls below a specific threshold. ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Reset Threshold** | 2.18V (Typical) | | **Output Stage** | Push-Pull (Active Low) | | **Supply Voltage Range** | 1.0V to 5.5V | | **Reset Timeout Period** | 150 ms (Minimum) | | **Operating Temperature** | -40°C to +105°C | | **Package Type** | SC-70 (3-lead) | | **Mounting Type** | Surface Mount | --- ### 2. Functional Description The device ensures that a system does not attempt to operate during power-up, power-down, or "brownout" conditions. * **Voltage Monitoring:** It continuously monitors the $V_{CC}$ pin. If the voltage drops below the fixed threshold (2.18V for the R22 variant), the $\overline{RESET}$ output is activated. * **Reset Pulse:** Once $V_{CC}$ rises above the threshold, the reset signal remains active for a "timeout period" (approx. 150ms) to allow the system clock to stabilize. * **Push-Pull Output:** Unlike "Open-Drain" versions, this part has a Push-Pull configuration, meaning it does not require an external pull-up resistor to drive the logic level high. --- ### 3. Part Number Breakdown (Nomenclature) The alphanumeric code provides specific details about the chip's configuration: | Code Segment | Meaning | | :--- | :--- | | **ADM1815** | Base Model Number (Microprocessor Reset Circuit) | | **R22** | Threshold Voltage code (2.18V) | | **AKSZ** | Package code (SC-70) and Pb-free/RoHS compliance | | **R7** | Packaging format (7-inch Tape and Reel, 3000 units) | --- ### 4. Typical Application Circuit The ADM1815 is typically placed between the power supply and the microcontroller. ```mermaid graph LR VCC[Power Supply 3.3V] --- VCC_Pin(ADM1815 VCC) VCC_Pin --- GND(Ground) VCC_Pin --- Reset_Out(RESET Output) Reset_Out --> MCU_Reset[Microcontroller Reset Pin] ``` ### 5. Common Use Cases * **Consumer Electronics:** Ensuring clean startups for handheld devices. * **Industrial Systems:** Preventing data corruption during power loss. * **Automotive:** Monitoring logic rails in infotainment or sensor modules. ---