Overview
The STM705M6F is a 5 V voltage supervisor IC produced by STMicroelectronics. This component is designed to monitor the voltage supply and provide a reset signal to microcontrollers or other digital circuits when the voltage falls below a specified threshold. It is part of the STM705 series, which includes various models with different reset threshold voltages and output configurations.
The STM705M6F is particularly useful in ensuring that digital systems operate reliably by preventing them from running with an insufficient power supply, which could lead to unpredictable behavior or data corruption.
Key Specifications
| Parameter | Description | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| VCC Operating Voltage | Supply voltage | 1.2 | - | 5.5 | V |
| ICC Supply Current | VCC supply current | 25 | 40 | 60 | μA |
| VRST Reset Threshold | Reset threshold voltage | 4.50 | 4.65 | 4.75 | V |
| trec Reset Time-out Period | RST pulse width | 140 | 200 | 280 | ms |
| tWD Watchdog Timeout Period | Watchdog timeout period | 1.12 | 1.60 | 2.24 | s |
| TA Operating Temperature | Ambient operating temperature | -40 | - | 85 | °C |
Key Features
- Precision VCC Monitor: Monitors the supply voltage and asserts a reset signal when VCC falls below the reset threshold (VRST) between 4.50 V and 4.75 V for the STM705M6F.
- Watchdog Timer: Includes a watchdog timer that triggers a reset if the watchdog input (WDI) does not see a rising or falling edge within 1.6 seconds.
- Manual Reset Input: Features a manual reset input (MR) that asserts the reset output when driven low.
- Power-Fail Comparator: Includes a power-fail comparator (PFI/PFO) to monitor an external voltage and provide a signal when it falls below a specified level.
- Low Supply Current: Operates with a low supply current of 40 μA (typical).
- Guaranteed RST Assertion: Ensures the reset output is asserted down to VCC = 1.0 V.
- Operating Temperature Range: Operates over an industrial temperature range of -40 °C to 85 °C.
- RoHS Compliance: Lead-free components compliant with the RoHS directive.
Applications
The STM705M6F is suitable for a variety of applications where reliable voltage monitoring and reset functionality are crucial:
- Embedded Systems: Ensures microcontrollers and other digital circuits operate within valid voltage ranges.
- Industrial Control Systems: Provides robust voltage monitoring in industrial environments.
- Automotive Systems: Although the STM705M6F itself is not automotive grade, the series includes automotive-grade options like the STM706.
- Consumer Electronics: Used in various consumer devices to prevent malfunction due to low voltage conditions.
Q & A
- What is the primary function of the STM705M6F?
The primary function of the STM705M6F is to monitor the supply voltage and assert a reset signal to microcontrollers or other digital circuits when the voltage falls below a specified threshold.
- What is the reset threshold voltage for the STM705M6F?
The reset threshold voltage for the STM705M6F is between 4.50 V and 4.75 V.
- How does the watchdog timer function in the STM705M6F?
The watchdog timer triggers a reset if the watchdog input (WDI) does not see a rising or falling edge within 1.6 seconds.
- What is the purpose of the manual reset input (MR)?
The manual reset input (MR) asserts the reset output when driven low, allowing for manual reset of the system.
- What is the power-fail comparator used for?
The power-fail comparator monitors an external voltage and provides a signal when it falls below a specified level.
- What is the typical supply current of the STM705M6F?
The typical supply current of the STM705M6F is 40 μA.
- What is the operating temperature range of the STM705M6F?
The operating temperature range of the STM705M6F is -40 °C to 85 °C.
- Is the STM705M6F RoHS compliant?
Yes, the STM705M6F is RoHS compliant, using lead-free components.
- How long does the reset output stay low after VCC rises above the reset threshold?
The reset output stays low for at least the reset time-out period (trec), which is typically 200 ms.
- Can the watchdog function be disabled?
Yes, the watchdog function can be disabled by allowing the WDI pin to float.
