1. One-Sentence Description
The MAX708TESA+T is a high-precision, low-power microprocessor (μP) monitoring chip designed for +3V to +5V power systems. It integrates reset, watchdog timer, power-fail warning, and dual reset output functions to ensure reliable system operation under abnormal voltage conditions.
2. Core Features
- Dual Reset Outputs: Provides independent high-level (RESET) and low-level (RESET) reset signals to compatible with different logic level requirements.
- Wide Voltage Range: Supports +3.0V to +5.5V power input, adapting to various power supply scenarios.
- Precision Reset Thresholds: Selectable reset threshold voltages (2.63V/2.93V/3.08V) ensure timely system reset at critical voltages.
- Watchdog Timer: 1.6-second timeout window prevents program hang; supports pulse width detection (minimum 50ns).
- Manual Reset Input: Compatible with TTL/CMOS levels, supporting reset triggering by switches or logic signals.
- Power-Fail Warning: Built-in 1.25V threshold detector pre-warns of low battery or power fluctuations.
- Ultra-Low Power: Quiescent current of only 50μA (typical), extending battery life.
- Compact Packaging: Available in SO, PDIP, and μMAX packages to meet different space requirements.
3. Core Technical Specifications
| Parameter | Typical Value | Operating Conditions |
| Supply Voltage Range | 3.0V~5.5V | VCC=3.0V~5.5V |
| Reset Pulse Width | 200ms | VCC≥1V |
| Watchdog Timeout | 1.6s | VCC=3.3V |
| Quiescent Current | 50μA | VCC=3.0V |
| Power-Fail Threshold | 1.25V | PFI input adjustable |
| Operating Temperature | -40℃~+85℃ | MAX708TEUA model |
4. The Story Behind the Chip
The MAX708TESA+T continues the innovation legacy of Maxim Integrated (now part of Analog Devices) in power management. Its design purpose is to provide “non-stop” reliability for embedded systems, especially in scenarios with strict stability requirements such as industrial control and medical equipment. By integrating multiple protection functions (reset, watchdog, power-fail detection), it solves the pain points of traditional discrete solutions, such as numerous components and complex debugging, becoming a benchmark for single-chip integrated solutions.
5. Design Philosophy
- Redundant Protection: Dual reset outputs (RESET/RESET) ensure system responsiveness even if one signal fails.
- Flexible Configuration: Supports external resistor voltage division to adjust the power-fail threshold (PFI), adapting to different power rails.
- Anti-Interference Optimization: Schmitt trigger on the watchdog input suppresses noise-induced false triggering.
- Extreme Scenario Adaptation: Ensures valid reset signals even when VCC drops as low as 1V, addressing deep power-down scenarios.
6. Application Scenarios
- Battery-Powered Devices: Portable instruments, IoT terminals, extending battery life via low-power modes.
- Industrial Control Systems: PLCs, sensor nodes, preventing program crashes caused by voltage transients.
- Automotive Electronics: Combined with wide-temperature models (e.g., MAX708TMJA), meeting -40℃~+125℃ extreme environment requirements.
- Medical Equipment: Ventilators, patient monitors, ensuring safe shutdown during power anomalies.
- Servers and Communication Equipment: Dual-power monitoring (e.g., +3.3V and +5V systems).
7. Unique Advantages
- Dual Reset Signal Outputs: A rare RESET/RESET dual-channel design in the industry, supporting mixed-logic systems (e.g., driving both CMOS and TTL loads).
- Watchdog Disable Function: MAX706AP/AR/AS/AT series allow watchdog disable via WDI floating, while MAX708TESA+T enables it by default, balancing flexibility and safety.
- Instant Power-Fail Response: PFO output triggers earlier than RESET, gaining emergency processing time for the system.
- Minimal Peripheral Circuit: Only a few resistors and capacitors are needed to implement a complete monitoring solution, reducing BOM costs.
8. What Engineers Must Know When Selecting
- Threshold Matching: Select reset thresholds (2.63V/2.93V/3.08V) according to the system’s core voltage to ensure reliable reset below VCC_min.
- Watchdog Configuration: If the MCU has no active watchdog feeding mechanism, enable the watchdog and set a reasonable WDI pulse interval.
- Power Integrity: Add a 0.1μF decoupling capacitor to the VCC input; in high-frequency noise environments, consider adding a bead filter.
- Package Compatibility: μMAX packages are suitable for space-sensitive designs, while PDIP packages facilitate manual soldering and debugging.
- Certification Compliance: For industrial-grade models (e.g., MAX708TMJA), confirm temperature ratings and certification standards (e.g., AEC-Q100).
Conclusion: The MAX708TESA+T, with its high integration, reliability, and flexible configuration, is an ideal choice for modern embedded systems. Whether in consumer electronics or industrial control, it acts as an “invisible guardian” to protect system safety.
Contact:
Sylvia Xu | ECSource Components Co.,Limited
Top 10 Test Laboratory Distributors in Asia.
D-U-N-S Number:655918890 | ISO90001 Certificated Company
Phone/Whatsapp: 0086-19806586673
Email:sylvia@ecsource.net
Line Card : FPGA, RF, MEMORY,CONNECTOR,Power
