Overview
The ADM691AARN-REEL, produced by Analog Devices Inc., is part of the ADM691A/ADM693A/ADM800L/ADM800M family of supervisory circuits. These circuits provide comprehensive single-chip solutions for power supply monitoring and battery control functions in microprocessor systems. The ADM691A is designed to offer power-on reset output during power-up, power-down, and brownout conditions, ensuring the circuit remains operational even when VCC is as low as 1 V. It also includes battery backup switching for CMOS RAM and other low-power logic, a watchdog timer, and a 1.25 V threshold detector for power fail warning and low battery detection.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Test Conditions/Comments |
|---|---|---|---|---|---|
| Operating Voltage Range (VCC) | 0 | - | 5.5 | V | - |
| Operating Voltage Range (VBATT) | - | - | 5.5 | V | - |
| VOUT Output Voltage | VCC - 0.05 | VCC - 0.02 | VCC - 0.3 | V | IOUT = 25 mA, IOUT = 250 mA |
| VCC to VOUT Output Resistance | 0.8 | 1.2 | - | Ω | VCC = 4.5 V |
| PFI Input Threshold (ADM69xA) | 1.2 | 1.25 | 1.3 | V | VCC = 5 V |
| PFO Output Voltage | 0.4 | - | 3.5 | V | ISINK = 3.2 mA, ISOURCE = 1 µA |
| CEIN Leakage Current | ±0.005 | ±1 | - | µA | Disable Mode |
| CEIN to CEOUT Resistance | 40 | 150 | - | Ω | Enable Mode |
Key Features
- Low Power Consumption: The ADM691A has a low standby current of approximately 1 µA, making it suitable for battery-powered applications.
- Precision Voltage Monitor: The device features a precision voltage monitor with ±2% tolerance.
- Watchdog Timer: Includes a watchdog timer that can be set to 200 ms or adjusted, ensuring system reliability.
- Battery Backup Switching: Automatic battery backup switching for CMOS RAM and other low-power logic.
- Fast Onboard Gating of Chip Enable Signals: Provides fast onboard gating of chip enable signals.
- Multiple Package Options: Available in 16-pin DIP, SO, and TSSOP packages.
Applications
- Microprocessor Systems: Ideal for monitoring and controlling power supplies in microprocessor-based systems.
- Computers and Controllers: Used in various computer and controller applications to ensure reliable power supply and battery backup.
- Intelligent Instruments: Suitable for intelligent instruments that require precise power monitoring and control.
- Automotive Systems: Applied in automotive systems for critical power monitoring and battery management.
Q & A
- What is the primary function of the ADM691A?
The primary function of the ADM691A is to provide power supply monitoring and battery control functions in microprocessor systems.
- What are the operating voltage ranges for VCC and VBATT?
The operating voltage range for VCC is 0 to 5.5 V, and for VBATT, it is up to 5.5 V.
- What is the typical standby current of the ADM691A?
The typical standby current of the ADM691A is approximately 1 µA.
- Does the ADM691A include a watchdog timer?
Yes, the ADM691A includes a watchdog timer that can be set to 200 ms or adjusted.
- What types of packages are available for the ADM691A?
The ADM691A is available in 16-pin DIP, SO, and TSSOP packages.
- What is the purpose of the PFI input threshold?
The PFI input threshold is used for power fail warning, low battery detection, or to monitor a power supply other than +5 V.
- How does the battery backup switching work?
The device automatically switches to battery backup for CMOS RAM and other low-power logic when the main power supply fails.
- What is the CEIN to CEOUT resistance in enable mode?
The CEIN to CEOUT resistance in enable mode is between 40 Ω and 150 Ω.
- What are some common applications of the ADM691A?
Common applications include microprocessor systems, computers, controllers, intelligent instruments, and automotive systems.
- How does the ADM691A handle power-on reset output?
The ADM691A provides power-on reset output during power-up, power-down, and brownout conditions.
