SGLS156F March   2003  – December 2016 TLC3702-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 LinCMOS™ Process
      2. 8.3.2 Electrostatic Discharge
      3. 8.3.3 Input Protection Circuit Operation
      4. 8.3.4 Positive ESD Transients
      5. 8.3.5 Negative ESD Transients
      6. 8.3.6 Circuit-Design Considerations
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Achieving Greater Noise Immunity
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Two-Phase Non-Overlapping Clock Generator
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|8
  • PW|8
Thermal pad, mechanical data (Package|Pins)
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

The inputs should always remain within the supply rails to avoid forward biasing the diodes in the electrostatic discharge (ESD) protection structure. If either input exceeds this range, the device is not damaged as long as the input is limited to less than 5 mA. To maintain the expected output state, the inputs must remain within the common-mode range. For example, at 25°C with VDD = 5 V, both inputs must remain between –0.2 V and 4 V to ensure proper device operation.

To ensure reliable operation, the supply should be decoupled with a capacitor (0.1 µF) that is positioned as close to the device as possible.

The TLC3702-Q1 has internal ESD-protection circuits that prevent functional failures at voltages up to 2000 V as tested under MIL-STD-883C, Method 3015.2; however, care should be exercised in handling these devices as exposure to ESD may result in the degradation of the device parametric performance.

9.2 Typical Applications

9.2.1 Achieving Greater Noise Immunity

TLC3702-Q1 TLC3702_Hysterysis.gif Figure 25. Application Adding Hysteresis to the TLC3702-Q1

9.2.1.1 Design Requirements

Figure 25 shows a typical topology used to introduce additional hysteresis. The additional hysteresis depends on the external resistors value and the supply voltage VDD.

Table 2. Design Parameters

PARAMETER VALUE
Supply voltage 5 V
VIN 2.5 V and 50 mV noise on top
Ceramic capacitor XR5 or XR7 50V
Hysteresis V+(H) – V+(-) 70 mV
R1, R2 27K 1%
R 1MΩ 1%

9.2.1.2 Detailed Design Procedure

This circuit is designed for stabilizing the output in a noisy environment by adding external hysteresis. The hysteresis is added by connecting a feedback resistor between positive input V+ and output VOUT. Output is high and VOUT = VDD, the positive input V+(H) =

Equation 1. TLC3702-Q1 TLC3702_Equation1.gif

Output is low and VOUT = GND, the positive input V+(L) =

Equation 2. TLC3702-Q1 TLC3702_Equation2.gif

From Equation 1 and Equation 2:

Equation 3. TLC3702-Q1 TLC3702_Equation3.gif
Equation 4. TLC3702-Q1 TLC3702_Equation4.gif

9.2.1.3 Application Curves

TLC3702-Q1 TLC3702_Figure26.gif
CH1 = VIN 2.5 V and noise of 50 mV on top CH2 = V+ voltage CH4 = output voltage
Figure 26. Output Voltage With No Hysteresis, R is Omitted
TLC3702-Q1 TLC3702_Figure27.gif
CH1 = VIN 2.5 V and noise of 50 mV on top CH2 = V+ voltage CH4 = output voltage
Figure 27. Output Voltage With Hysteresis

9.2.2 Two-Phase Non-Overlapping Clock Generator

TLC3702-Q1 appinfo_03_gls156.gif Figure 28. Two-Phase Non-Overlapping Clock Generator

9.2.2.1 Design Requirements

Table 3 lists the design parameters.

Table 3. Design Parameters

PARAMETER VALUE
Supply voltage 3 V to 12 V
Ceramic capacitor XR5 or XR7 50 V
Resistors 1%

9.2.2.2 Detailed Design Procedure

The first stage is a window comparator with positive feedback by connecting R6 between the comparator output and the positive input. That creates an external hysteresis depending on resistors R4, R5, R6 value and the supply voltage VDD.

Comparator output is high gives V+(H) =

Equation 5. TLC3702-Q1 TLC3702_Equation5.gif

Comparator output is low gives V+(L) =

Equation 6. TLC3702-Q1 TLC3702_Equation6.gif

The negative feedback between capacitor C1 and the comparator negative input allows the capacitor to charge between 2 threshold V+(H) and V+(L). The charging and discharging is exponential with time constant of R7C1. The charging and discharging have the same duration.

C1 is charging during the time when output is high and the voltage across it is:

Equation 7. TLC3702-Q1 TLC3702_Equation7.gif

The charging time is:

Equation 8. TLC3702-Q1 TLC3702_Equation8.gif

The charging and discharging time is:

Equation 9. TLC3702-Q1 TLC3702_Equation9.gif

and the oscillator frequency is:

Equation 10. TLC3702-Q1 TLC3702_Equation10.gif

For the circuit of Figure 28, V+(L) = 1.83 V, V+(H) = 10.17 V and period T = 3.43 mS

This circuit can also be used for Frequency Dithering in switch mode power supply to pass EMC compliance.

The second stage forms 2 window comparators with complementary outputs. One output 1OUT is high when

Equation 11. TLC3702-Q1 TLC3702_Equation11.gif

VDD and 2OUT is high when

Equation 12. TLC3702-Q1 TLC3702_Equation12.gif