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2 How to Make a TPHL Propagation Delay Measurement With Split Supplies

Note

Do not turn on power supply until all connections to the device are made to the board.

1. Set one channel of the DC power supply to output a -2.5 V voltage and set its current limit to 100 mA. After 

ensuring that this channel is disabled, connect GND/VEE to this supply.

2. Set one channel of the DC power supply to output a 2.5 V voltage and set its current limit to 100 mA. After 

ensuring that this channel is disabled, connect VCC to this supply.

3. Ensure that cables connecting to IN+SENSE, OUT+, and OUT- are matched length and impedance. Perform 

any deskewing if no matched cables are available. For this setup, IN- is a DC voltage reference so the 
cables used for IN- and IN- SENSE do not need to be matched.

4. On the signal generator output, set the function generator to produce a square wave output with 100 mVpp 

at 10-MHz, with a 0 V DC offset. This results in a 50 mV overdrive and 50 mV underdrive. Disable the signal 
generator output. Connect the signal generator output to IN+.

5. Connect the inverting input, IN-, to ground to establish the threshold for the comparator at 0 V.
6. Connect OUTP and OUTN to a 50-Ω terminated channel on the oscilloscope. 

Note

 that with capacitors C7 

and C8 populated, the DC component of the outputs will be filtered.

7. Connect IN+SENSE, to another 50-Ω terminated scope channel.
8. Enable the VCC/VEE power supplies.
9. Verify the total supply current is < 30 mA.
10. Enable the signal generator.
11. Monitor and verify the inputs from IN+SENSE and IN- is 0 V DC.
12. Monitor and verify the outputs for OUT+ and OUT-.

High Speed Pulse Generator

(<500 ps Rise/Fall Time, 50 Ohm 

Terminated)

V

EE 

= -2.5V

V

CC 

= 2.5V

IN- 

SENSE

OUT+

OUT-

IN+

IN-

IN+ 

SENSE

High Speed Oscilloscope

(50 Ohm Terminations)

CH.3

CH.4

CH.1

Legend 

Matched SMA cable length

SMA cable

GND

Figure 2-1. TLV3811 EVM Propagation Delay Setup

How to Make a TPHL Propagation Delay Measurement With Split Supplies

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4

TLV3811EVM User’s Guide

SNOU189 – MAY 2022

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Содержание TLV3811EVM

Страница 1: ...ts 8 4 Layout Guidelines 9 5 Schematic 11 6 Bill of Materials 12 List of Figures Figure 1 1 TLV3811EVM Board Top View 2 Figure 1 2 TLV3811 Block Diagram 2 Figure 1 3 TLV3811EVM Pin Assignments 3 Figur...

Страница 2: ...vide high speed signals to interconnect devices such as FPGAs with minimal power dissipation Figure 1 1 TLV3811EVM Board Top View 1 1 Features Low Propagation Delay Low Overdrive Dispersion High Toggl...

Страница 3: ...kes it easy to measure propagation delay since the reference voltage is known to be 0V Single supply option still available High Speed Functional Generator with fast rise fall time recommended 500 ps...

Страница 4: ...a 50 mV overdrive and 50 mV underdrive Disable the signal generator output Connect the signal generator output to IN 5 Connect the inverting input IN to ground to establish the threshold for the compa...

Страница 5: ...OUT reaches 0 V The propagation delay was measured at approximately 206 ps with the setup described Channel 4 OUT Channel 1 100mV peak to peak VOD 50mV VUD 50mV 10MHz Channel 3 OUT Figure 2 2 Quick St...

Страница 6: ...tion The recommended voltage range is from 2 7 V to 5 5 V Connect VCC VEE and SYS_GND using TP1 TP2 and TP3 respectively Figure 3 1 TLV3811EVM Supply Voltage Connection Board Setup www ti com 6 TLV381...

Страница 7: ...y the input signal generator otherwise they can be left uninstalled R1 0 R4 0 GND IN _SENSE IN _SENSE VCC VEE IN IN GND Figure 3 2 Input Side Schematic Without Optional Resistors R2 and R3 Additionall...

Страница 8: ...charging and discharging of the capacitors A higher duty cycle will result in a higher DC output voltage because the capacitors are charging more than they are discharging GND VCC VEE C7 0 1uF C8 0 1u...

Страница 9: ...lines Top Layer GND 1 Layer GND 2 Layer Bottom Layer Figure 4 1 Layers www ti com Layout Guidelines SNOU189 MAY 2022 Submit Document Feedback TLV3811EVM User s Guide 9 Copyright 2022 Texas Instruments...

Страница 10: ..._GND IN IN IN _SENSE IN _SENSE VCC VEE SYS_GND Figure 4 2 TLV3811 EVM Block Diagram Layout Guidelines www ti com 10 TLV3811EVM User s Guide SNOU189 MAY 2022 Submit Document Feedback Copyright 2022 Tex...

Страница 11: ...5 Schematic Figure 5 1 TLV3811 EVM Schematic www ti com Schematic SNOU189 MAY 2022 Submit Document Feedback TLV3811EVM User s Guide 11 Copyright 2022 Texas Instruments Incorporated...

Страница 12: ...5 J6 6 SMA Connector Receptacle Female Socket 50Ohm Board Edge End Launch Solder 0732511150 Molex Inc J7 J8 2 Header 100mil 2x1 Gold TH Header 2 54mm 2x1 TH HMTSW 102 07 G S 240 Samtec LBL1 1 Thermal...

Страница 13: ...ther than TI b the nonconformity resulted from User s design specifications or instructions for such EVMs or improper system design or c User has not paid on time Testing and other quality control tec...

Страница 14: ...These limits are designed to provide reasonable protection against harmful interference in a residential installation This equipment generates uses and can radiate radio frequency energy and if not in...

Страница 15: ...instructions set forth by Radio Law of Japan which includes but is not limited to the instructions below with respect to EVMs which for the avoidance of doubt are stated strictly for convenience and s...

Страница 16: ...any interfaces electronic and or mechanical between the EVM and any human body are designed with suitable isolation and means to safely limit accessible leakage currents to minimize the risk of electr...

Страница 17: ...R DAMAGES ARE CLAIMED THE EXISTENCE OF MORE THAN ONE CLAIM SHALL NOT ENLARGE OR EXTEND THIS LIMIT 9 Return Policy Except as otherwise provided TI does not offer any refunds returns or exchanges Furthe...

Страница 18: ...change without notice TI grants you permission to use these resources only for development of an application that uses the TI products described in the resource Other reproduction and display of thes...

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