### Overview: ADM823TYKSZ-R7 The **ADM823TYKSZ-R7** is a high-performance supervisory circuit designed by Analog Devices. It is primarily used to monitor power supply voltages and microprocessor activity, providing a reset signal to ensure the system starts up correctly and recovers from errors. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Reset Threshold** | 3.08V (Typical) | | **Supply Voltage (Vcc)** | 1.0V to 5.5V | | **Reset Timeout Period** | 140 ms (Minimum) | | **Watchdog Timeout** | 1.6 seconds (Typical) | | **Output Type** | Push-Pull, Active Low | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | SC-70-5 (Small Outline Transistor) | --- ### 2. Main Functions The device integrates three critical functions into a single small-form-factor package: 1. **Power-On Reset (POR):** It generates a reset pulse when the power supply (Vcc) rises above a preset threshold, ensuring the processor starts from a known state. 2. **Supply Voltage Monitoring:** If the voltage drops below the threshold (3.08V), the reset output triggers to prevent unstable operation. 3. **Watchdog Timer:** The device monitors the processor's activity. The processor must "kick" the watchdog (toggle the WDI pin) periodically. If it fails to do so (due to a software crash), the ADM823 triggers a reset. 4. **Manual Reset Input:** Allows a physical button or an external logic signal to force a system reset. --- ### 3. Pin Configuration The SC-70-5 package features 5 pins: | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | **$\overline{RESET}$** | Active-low output that stays low during reset. | | 2 | **GND** | Ground reference (0V). | | 3 | **$\overline{MR}$** | Manual Reset Input; active-low. | | 4 | **WDI** | Watchdog Input; must be toggled to prevent reset. | | 5 | **Vcc** | Power supply input and monitored voltage. | --- ### 4. Typical Application Circuit The circuit typically involves connecting the reset output directly to the processor's reset pin. ```c // Logic Flow for Watchdog Maintenance void main_loop() { while(1) { Perform_System_Tasks(); Toggle_WDI_Pin(); // Prevents ADM823 from resetting the CPU Delay_Less_Than_1.6s(); } } ``` --- ### 5. Summary of the "R7" Suffix The suffix **-R7** indicates the packaging method: * **R**: Tape and Reel. * **7**: 7-inch reel diameter (typically containing 3,000 units).