SCES578J June 2003 – September 2017 SN74AUP1G14
PRODUCTION DATA.
- 1 Features
- 2 Applications
- 3 Description
- 4 Revision History
- 5 Pin Configuration and Functions
-
6 Specifications
- 6.1 Absolute Maximum Ratings
- 6.2 ESD Ratings
- 6.3 Recommended Operating Conditions
- 6.4 Thermal Information
- 6.5 Electrical Characteristics
- 6.6 Switching Characteristics: CL = 5 pF
- 6.7 Switching Characteristics: CL = 10 pF
- 6.8 Switching Characteristics: CL = 15 pF
- 6.9 Switching Characteristics: CL = 30 pF
- 6.10 Operating Characteristics
- 6.11 Typical Characteristics
- 7 Parameter Measurement Information
- 8 Detailed Description
- 9 Application and Implementation
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
9 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.
9.1 Application Information
Mechanical input elements, such as push buttons or rotary knobs, offer simple ways to interact with electronic systems. Typically, these elements have recoil or bouncing, where the mechanical element makes and breaks contact multiple times during human interaction. This bouncing can cause one or more repeated signals to be passed, triggering multiple actions when only a single input was intended. One potential solution to mitigating these multiple inputs is by utilizing a Schmitt-trigger to create a debounce circuit. Figure 7 shows an example of this solution.
9.2 Typical Application
The input due to the push button switches multiple times, causing the output of a non Schmitt-trigger device to trigger multiple times, while the Schmitt-trigger input device with RC delay limits the output pulse to a single pulse desired by the user. The separated positive and negative input voltage threshold values prevent multiple triggers from occurring, see the Electrical Characteristics table for VT+, VT-, and Vhys values.
Figure 7. Push Button Debounce Circuit Schematic
9.2.1 Design Requirements
This device uses CMOS technology and has balanced output drive. Take care to avoid bus contention because it can drive currents that would exceed maximum limits. The drive strength also creates fast edges into light loads so routing and load conditions should be considered to prevent ringing.
9.2.2 Detailed Design Procedure
- Recommended Input Conditions:
- For specified high and low levels, see (VT+ and VT-) in the Electrical Characteristics table.
- Inputs are overvoltage tolerant allowing them to go as high as (VI max) in the Recommended Operating Conditions table at any valid VCC.
- Recommended Output Conditions:
- Load currents should not exceed (IO max) per output and should not exceed (Continuous current through VCC or GND) total current for the part. These limits are located in the Absolute Maximum Ratings table.
9.2.3 Application Curves
