Overview
The ADM709TAR-REEL is a power supply monitor integrated circuit (IC) designed by Analog Devices Inc. This device is part of the ADM709 series, which provides system reset functionality during power-up, power-down, and brownout conditions. The ADM709 ensures that the microprocessor remains in a reset state until the power supply voltage stabilizes above a predefined threshold, thereby preventing system malfunctions due to voltage fluctuations.
Key Specifications
| Parameter | Min | Typ | Max | Units | Test Conditions/Comments |
|---|---|---|---|---|---|
| VCC Operating Voltage Range | 1.0 | 5.5 | V | TA = 0°C to +70°C | |
| 1.0 | 5.5 | V | TA = –40°C to +85°C | ||
| Supply Current | 35 | 85 | 110 | µA | VCC < 3.6 V, TA = 0°C to +70°C |
| 35 | 110 | 200 | µA | VCC < 3.6 V, TA = –40°C to +85°C | |
| 65 | 150 | 200 | µA | VCC < 5.5 V, TA = 0°C to +70°C | |
| 65 | 200 | µA | VCC < 5.5 V, TA = –40°C to +85°C | ||
| Reset Threshold (ADM709T) | 3.00 | 3.08 | 3.15 | V | |
| VCC to RESET Delay | 20 | µs | VCC = Reset Threshold max–min | ||
| RESET Active Time-Out Period | 140 | 280 | 380 | ms | VCC = Reset Threshold max, VCC Rising |
| RESET Output Voltage | 0.3 | V | ISINK = 1.2 mA, VCC ≥ 1.0 V |
Key Features
- Precision Supply Voltage Monitor for +5 V, +3.3 V, and +3 V power supplies.
- Low quiescent current of 35 µA (typical).
- 140 ms (minimum) power-on reset pulse.
- Low cost and compact 8-pin DIP and SOIC packages.
- RESET output remains operational with VCC as low as 1 V.
- Upgrade for MAX709.
Applications
- Microprocessor Systems
- Computers
- Controllers
- Intelligent Instruments
- Critical Microprocessor Monitoring
- Automotive Systems
Q & A
- What is the primary function of the ADM709TAR-REEL?
The primary function is to monitor the power supply voltage and generate a system reset during power-up, power-down, and brownout conditions.
- What are the available supply-voltage threshold levels for the ADM709?
The ADM709 is available for monitoring +5 V, +3.3 V, and +3 V power supplies.
- What is the typical quiescent current of the ADM709?
The typical quiescent current is 35 µA.
- How long does the RESET output remain low after VCC rises above the threshold?
The RESET output remains low for a minimum of 140 ms after VCC rises above the threshold.
- In what packages is the ADM709 available?
The ADM709 is available in 8-pin DIP and SOIC packages.
- What is the minimum operating voltage for the RESET output?
The RESET output remains operational with VCC as low as 1 V.
- What are some common applications of the ADM709?
Common applications include microprocessor systems, computers, controllers, intelligent instruments, and automotive systems.
- How does the ADM709 handle power-on reset?
The ADM709 holds the RESET output low for 140 ms after VCC rises above the threshold during power-on.
- What is the purpose of the VCC to RESET delay?
The VCC to RESET delay ensures that the system reset is triggered correctly when the power supply voltage crosses the reset threshold.
- Can the ADM709 be used in harsh temperature environments?
Yes, the ADM709 operates over a temperature range of –40°C to +85°C.
