Overview
The TL7705AIDR is a supply-voltage supervisor integrated circuit from Texas Instruments, designed specifically for use as a reset controller in microcomputer and other digital systems. This device is part of the TL77xxA family and is particularly suited for applications requiring a 5-volt supply, such as TTL systems and microcomputer systems like the TMS7000.
The TL7705AIDR ensures that the system resets properly during power-up and power-down cycles, and it monitors the supply voltage to prevent the system from operating under undervoltage conditions. It features a temperature-compensated voltage reference and an externally adjustable pulse duration, making it versatile for various system requirements.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage Range | 3.6 to 18 | V |
| Threshold Voltage (Vt) | 4.55 | V |
| Hysteresis (Vhys) | 15 mV | mV |
| High-level Output Voltage (VOH) | VCC - 1.5 | V |
| Low-level Output Voltage (VOL) | 0.4 | V |
| High-level Output Current (IOH) | -16 mA | mA |
| Low-level Output Current (IOL) | 16 mA | mA |
| Operating Free-air Temperature Range | -40 to 85 | °C |
| Package Type | SOIC (8 pins) | |
| Thermal Resistance Junction-ambient (RθJA) | 97 °C/W | °C/W |
Key Features
- Wide Supply-Voltage Range: Operates over a supply voltage range of 3.6 V to 18 V.
- Externally Adjustable Pulse Duration: The time delay can be adjusted using an external capacitor connected to the CT input.
- Temperature-Compensated Voltage Reference: Includes a stable reference voltage source that varies less than 10 mV over the supply voltage range and 16 mV over the ambient temperature range from -40°C to +85°C.
- Dual Reset Outputs: Provides both active-low (RESET) and active-high (RESET) reset signals.
- Low Supply Current: Typical supply current of 1.8 mA to 3 mA.
Applications
- TTL Systems and Microcomputers: Suitable for systems requiring a 5-volt supply, such as the TMS7000 microcomputer.
- Embedded Systems: Used in various embedded systems to ensure proper reset and voltage monitoring.
- Industrial Control Systems: Can be used in industrial control systems where reliable voltage monitoring is critical.
- Consumer Electronics: Applied in consumer electronics to manage power-up and power-down sequences.
Q & A
- What is the primary function of the TL7705AIDR?
The primary function of the TL7705AIDR is to act as a supply-voltage supervisor and reset controller in microcomputer and digital systems.
- What is the threshold voltage for the TL7705AIDR?
The threshold voltage (Vt) for the TL7705AIDR is 4.55 V.
- How is the pulse duration adjusted in the TL7705AIDR?
The pulse duration is adjusted using an external capacitor connected to the CT input, with the delay time calculated as td = 1.3 × 10^4 × CT, where CT is in farads.
- What is the operating temperature range for the TL7705AIDR?
The operating temperature range for the TL7705AIDR is -40°C to 85°C.
- What type of packages is the TL7705AIDR available in?
The TL7705AIDR is available in SOIC (8 pins) and PDIP (8 pins) packages.
- How does the TL7705AIDR handle undervoltage conditions?
During an undervoltage condition, the RESET and RESET outputs become active until the supply voltage returns to the nominal value.
- What is the purpose of the reference voltage output in the TL7705AIDR?
The reference voltage output provides a stable voltage source that can be used in applications requiring a constant voltage.
- How does the TL7705AIDR ensure stability during fast transients in the supply voltage?
An external capacitor (typically 0.1 µF) connected to the REF output helps reduce the influence of fast transients in the supply voltage.
- What are the high-level and low-level output currents for the TL7705AIDR?
The high-level output current (IOH) is -16 mA, and the low-level output current (IOL) is 16 mA.
- What is the thermal resistance junction-ambient (RθJA) for the TL7705AIDR?
The thermal resistance junction-ambient (RθJA) for the TL7705AIDR is 97 °C/W.
