3-Pin Microprocessor Power Supply Supervisors # CAT810LEURT10 Technical Documentation
## 1. Application Scenarios
### Typical Use Cases
The CAT810LEURT10 is a microprocessor (μP) supervisory circuit designed to monitor power supplies in digital systems. Key applications include:
- Power-On Reset Control : Provides reliable reset signals during power-up, power-down, and brown-out conditions
- Battery-Powered Systems : Monitors battery voltage in portable devices to prevent data corruption
- Embedded Systems : Ensures proper microcontroller initialization in industrial controllers and IoT devices
- Automotive Electronics : Monitors power rails in infotainment systems and engine control units
- Medical Equipment : Provides critical power monitoring in patient monitoring devices and diagnostic equipment
### Industry Applications
- Consumer Electronics : Smartphones, tablets, wearables, and gaming consoles
- Industrial Automation : PLCs, motor controllers, and sensor networks
- Telecommunications : Network switches, routers, and base station equipment
- Automotive : ADAS systems, telematics, and in-vehicle networking
- Medical Devices : Portable monitors, infusion pumps, and diagnostic instruments
### Practical Advantages and Limitations
Advantages:
- Low Power Consumption : Typical standby current of 3.5μA extends battery life
- Precise Voltage Monitoring : ±1.5% threshold accuracy ensures reliable operation
- Small Package : SOT-23-5 package saves board space in compact designs
- Wide Operating Range : 1.0V to 5.5V supply voltage compatibility
- Manual Reset Capability : Additional reset input for system testing
Limitations:
- Fixed Threshold Voltage : 2.93V threshold may not suit all applications
- Limited Customization : No adjustable threshold options available
- Temperature Range : Industrial temperature range (-40°C to +85°C) may not suit extreme environments
- Single Channel : Monitors only one voltage rail
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Pitfall 1: Insufficient Bypass Capacitance
- Problem : Voltage spikes causing false resets
- Solution : Place 0.1μF ceramic capacitor within 10mm of VCC pin
Pitfall 2: Improper Reset Timing
- Problem : Microcontroller reset before stable power
- Solution : Ensure reset timeout period (140ms typical) matches μP requirements
Pitfall 3: Signal Integrity Issues
- Problem : Noise on reset line causing system instability
- Solution : Route reset signal away from noisy digital lines and use pull-up resistor
### Compatibility Issues with Other Components
Microcontroller Interfaces:
- Compatible with most 3.3V and 5V microcontrollers
- Ensure reset polarity matches μP requirements (active-low)
- Verify timing requirements for specific microcontroller families
Power Supply Compatibility:
- Works with LDO regulators, switching regulators, and battery sources
- Monitor supply voltage must be within 1.0V to 5.5V range
- Consider power sequencing in multi-rail systems
### PCB Layout Recommendations
Power Supply Routing:
- Use star-point grounding for analog and digital grounds
- Route VCC trace directly from power source with minimal vias
- Maintain continuous ground plane beneath the device
Signal Routing:
- Keep reset output trace short and direct to microcontroller
- Route MR (manual reset) input with series resistor for ESD protection
- Avoid crossing digital signal lines over reset traces
Component Placement:
- Position bypass capacitor adjacent to VCC pin (Pin 1)
- Place pull-up resistor close to reset output (Pin 4)
- Maintain minimum 2mm clearance from high-frequency components
## 3. Technical Specifications
### Key Parameter Explan
