Overview
The ADM691AR, produced by Analog Devices Inc., is a supervisory circuit IC designed specifically for use in 5V CMOS technology. This component is part of the ADM691 family and serves as a processor supervisor, providing essential functions for power supply monitoring and battery control in microprocessor systems. It features active high and active low signal outputs in a push-pull configuration, making it versatile for various system requirements.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Test Conditions/Comments |
|---|---|---|---|---|---|
| Operating Voltage Range (VCC) | 4.75 | 5.5 | V | ||
| Operating Voltage Range (VBATT) | 2.0 | 4.25 | V | ||
| Reset Voltage Threshold | 4.5 | 4.65 | 4.75 | V | |
| Reset Threshold Hysteresis | 15 | mV | |||
| VCC to RESET Delay | 80 | µs | |||
| Power Up Reset Timeout Period (Internal Oscillator) | 140 | 200 | 280 | ms | |
| Watchdog Timeout Period (Internal Oscillator) | 1.0 | 1.6 | 2.25 | s | Long Period |
| Minimum WDI Input Pulse Width | 100 | ns | |||
| Operating Temperature | -40 | 85 | °C | ||
| Supply Current (Excludes IOUT) | 1 | 1.95 | mA | IOUT = 100 mA | |
| Battery Standby Current | 0.6 | 1 | µA | VCC = 0 V, VBATT = 2.8 V |
Key Features
- Power-on Reset Output: Provides reset output during power-up, power-down, and brownout conditions, operational with VCC as low as 1 V.
- Battery Backup Switching: Automatically switches to battery backup for CMOS RAM, CMOS microprocessors, or other low-power logic.
- Watchdog Timer: Generates a reset pulse if the watchdog timer is not toggled within a specified time.
- Power Fail Warning: Includes a 1.25 V threshold detector for power fail warning, low battery detection, or monitoring a power supply other than +5 V.
- Adjustable Reset and Watchdog Timeout Periods: Allows for adjustable reset and watchdog timeout periods.
- Write Protection of CMOS RAM or EEPROM: Provides write protection for CMOS RAM or EEPROM.
- Chip Enable Signals: Fast onboard gating of chip enable signals.
- Low Power Consumption: Features low power consumption with a supply current of 1.95 mA (excluding IOUT).
- High Reliability: Fabricated using an advanced epitaxial CMOS process with high reliability and minimal voltage drop.
Applications
- Microprocessor Systems: Ideal for monitoring and controlling microprocessor systems.
- Computers and Controllers: Used in various computer and controller applications.
- Intelligent Instruments: Suitable for intelligent instruments that require precise power monitoring.
- Automotive Systems: Applied in automotive systems for reliable power management.
- Critical Power Monitoring: Essential for critical power monitoring in various industrial and embedded systems.
Q & A
- What is the primary function of the ADM691AR?
The primary function of the ADM691AR is to provide power supply monitoring and battery control functions in microprocessor systems.
- What is the operating voltage range for VCC?
The operating voltage range for VCC is 4.75 V to 5.5 V.
- What is the reset voltage threshold for the ADM691AR?
The reset voltage threshold is between 4.5 V and 4.75 V.
- Does the ADM691AR have adjustable watchdog timeout periods?
- What is the minimum operating temperature for the ADM691AR?
The minimum operating temperature is -40°C.
- What is the maximum supply current (excluding IOUT) for the ADM691AR?
The maximum supply current (excluding IOUT) is 1.95 mA.
- Does the ADM691AR provide write protection for CMOS RAM or EEPROM?
- What is the purpose of the watchdog timer in the ADM691AR?
The watchdog timer generates a reset pulse if it is not toggled within a specified time.
- How does the battery backup switching work in the ADM691AR?
The battery backup switching automatically connects VOUT to whichever is higher between VCC and VBATT, with a switchover threshold of 70 mV.
- What are some common applications of the ADM691AR?
