Overview
The TL7705ACDR, produced by Texas Instruments, is a supply-voltage supervisor integrated circuit designed for use as a reset controller in microcomputer systems. This device is part of the TL77xxA family and is specifically tailored for applications requiring a 5-volt supply, such as TTL systems and microcomputer systems like the TMS7000.
During power-up, the RESET output becomes active when the VCC voltage approaches 3.6 V, and after a programmable delay, the outputs become inactive. The device also monitors for undervoltage conditions during normal operation and activates the RESET outputs accordingly.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Threshold Voltage (Vt) | 4.55 | V | ||
| Output Pulse Duration (CT = 0.1 µF) | 0.65 | 1.2 | 2.6 | msec |
| Input Pulse Duration at RESIN | 0.4 | µs | ||
| Propagation Delay Time (RESIN to RESET) | 1 | µs | ||
| Rise Time (RESET) | 0.2 | µs | ||
| Fall Time (RESET) | 0.2 | 3.5 | µs | |
| Operating Temperature Range | -40 | 85 | °C | |
| Package Types | SOIC (8), PDIP (8), SO (8) |
Key Features
- Programmable delay time using an external capacitor.
- Active low RESET and RESET outputs.
- Threshold voltage of 4.55 V, suitable for 5-volt supply systems.
- Automatic reset when the supply voltage falls below the threshold.
- Protection against fast transients in the supply voltage through an external capacitor connected to REF.
- Multiple package options: SOIC (8), PDIP (8), and SO (8).
Applications
- TTL systems and microcomputer systems requiring a 5-volt supply, such as the TMS7000.
- Microprocessor and memory circuits where reliable power-on reset is essential.
- Analog circuits that operate with a 5-volt supply voltage.
- Any system requiring automatic reset upon undervoltage conditions.
Q & A
- What is the primary function of the TL7705ACDR?
The primary function of the TL7705ACDR is to act as a supply-voltage supervisor and reset controller in microcomputer systems.
- What is the threshold voltage for the TL7705ACDR?
The threshold voltage for the TL7705ACDR is 4.55 V.
- How is the delay time programmed in the TL7705ACDR?
The delay time is programmed using an external capacitor connected to the REF pin.
- What happens when the supply voltage falls below the threshold voltage?
When the supply voltage falls below the threshold voltage, the RESET outputs become active.
- What types of packages are available for the TL7705ACDR?
The TL7705ACDR is available in SOIC (8), PDIP (8), and SO (8) packages.
- How does the device protect against fast transients in the supply voltage?
The device protects against fast transients by using an external capacitor connected to the REF pin.
- What is the operating temperature range for the TL7705ACDR?
The operating temperature range for the TL7705ACDR is -40°C to 85°C.
- Can the TL7705ACDR be used in analog circuits?
Yes, the TL7705ACDR can be used in analog circuits that operate with a 5-volt supply voltage.
- What are the typical applications of the TL7705ACDR?
Typical applications include TTL systems, microcomputer systems, and any system requiring automatic reset upon undervoltage conditions.
- How do the RESET outputs behave during power-up and power-down?
During power-up, the RESET outputs become active when VCC approaches 3.6 V and remain active for a programmable delay. During power-down, the outputs remain active until VCC falls below 2 V.
