Overview
The STM708RM6E is a supervisory circuit produced by STMicroelectronics, designed to provide essential microprocessor supervisory functions. This device is part of the STM70x family and is self-contained, offering a precision voltage reference and comparator to monitor the VCC input for out-of-tolerance conditions. It features a simple reset/power-on reset functionality, making it a reliable component for ensuring system stability and integrity.
Key Specifications
| Parameter | Value | Conditions |
|---|---|---|
| Reset Threshold Voltage (VRST) | 2.63 V | - |
| Reset Timeout Period (trec) | 200 ms (typ.) | - |
| Watchdog Timer Period | 1.6 s (typ.) | - |
| Supply Current | 40 µA (typ.) | VCC = 3 V to 5.5 V |
| Package Type | 8-pin SOIC | - |
| Operating Temperature Range | -40°C to +85°C | - |
| Power-Fail Threshold (VPFI) | Internal reference voltage | - |
Key Features
- Reset Output: Active-low (RST) and active-high (RST) reset outputs available, depending on the device variant.
- Watchdog Timer: Internal 1.6-second watchdog timer to detect an out-of-control MCU. The timer can be disabled by floating the WDI pin.
- Manual Reset Input (MR): Logic low on MR asserts the reset output, which remains asserted as long as MR is low and for the reset timeout period after MR returns high.
- Power-Fail Comparator (PFI/PFO): Monitors the power supply and generates a reset if the voltage falls below the power-fail threshold.
- Low Supply Current: Typical supply current of 40 µA, making it power-efficient.
- Guaranteed Reset Assertion: Reset output is guaranteed to be asserted down to VCC = 1.0 V.
Applications
- Microprocessor Systems: Ensures system stability by monitoring the power supply and asserting a reset if the voltage drops below the threshold.
- Embedded Systems: Ideal for use in embedded systems requiring reliable power-on reset and watchdog functionality.
- Industrial Automation: Suitable for industrial automation systems where robust supervisory functions are necessary.
- Consumer Electronics: Used in various consumer electronics to ensure reliable operation and prevent system crashes.
Q & A
- What is the primary function of the STM708RM6E?
The primary function of the STM708RM6E is to provide microprocessor supervisory functions, including reset, watchdog, and power-fail detection.
- What is the reset threshold voltage for the STM708RM6E?
The reset threshold voltage is 2.63 V.
- How long does the reset output stay low after being triggered?
The reset output stays low for at least the reset timeout period, which is typically 200 ms.
- Can the watchdog timer be disabled?
Yes, the watchdog timer can be disabled by allowing the WDI pin to float or by tri-stating the driver connected to WDI.
- What is the purpose of the power-fail comparator?
The power-fail comparator monitors the power supply and generates a reset if the voltage falls below the power-fail threshold.
- What is the typical supply current of the STM708RM6E?
The typical supply current is 40 µA.
- Down to what voltage is the reset output guaranteed?
The reset output is guaranteed down to VCC = 1.0 V.
- How can the manual reset input be triggered?
The manual reset input (MR) can be triggered by a logic low, which asserts the reset output.
- What package types are available for the STM708RM6E?
The STM708RM6E is available in an 8-pin SOIC package.
- What is the operating temperature range of the STM708RM6E?
The operating temperature range is -40°C to +85°C.
