Reply to "Design of a $10-20 DCS-TIU Port Tester Tool?"

stan2004OGR Forum Member

GRJ, what is the lead-spacing of the caps? It looks like 0.25" or 0.3"? I realize it's just a place-holder but the 3-D rendering shows a radial package which tend to be expensive and harder to find with such large lead spacing.

Point being if you go to DigiKey and search for 0.1uF 50V ceramic capacitor, you are overwhelmed with choices. While terminal wires can be manipulated to fit in whatever hole spacing, I think some guys would rather just be given a specific part number to use.

So another participant in a corporate Design-Review process was a representative from Purchasing who, rather than being asleep, was always chomping at the bit to nail down exact part numbers for good reason.

To that end, note that Adrian in his early post suggests he used the HCT version of the 123 chip:

http://www.newark.com/texas-in...ip16-5-5v/dp/25M8579

The HCT version has a lower threshold trigger voltage than the HC version. It probably doesn't make a difference in this application if using a trimmer to tune the voltage, but if you're after apples-to-apples, the DigiKey version would be:

https://www.digikey.com/produc.../296-2088-5-ND/38252

If anyone is putting together an "official" DigiKey parts list,

the 1N4148 diode could be:

https://www.digikey.com/produc...8/1N4148FS-ND/458603

And the least expensive flying-lead 9V battery-holder appears to be:

https://www.digikey.com/produc...232/36-232-ND/303804

1/4W 10K resistor could be:

https://www.digikey.com/produc...4JT10K0CT-ND/1830374

Other resistor values also available in the CF14.... "family" of 1/4W resistors at same price (4 cents each at qty 10).

330 ohms

https://www.digikey.com/produc...4JT330RCT-ND/1830338

100K ohms

https://www.digikey.com/produc...4JT100KCT-ND/1830399

Attachments

Hide

Images (4)

7/20/1811:43 AM

<div id="{%=id%}" class="reveal-modal small h-alert-modal-popup" data-reveal>
    <div class="first-modal-focus focus-utility-element" tabindex="0" aria-label="Inside Modal"></div>

<h4 id="{%=id%}_title" class="margin-bottom-10 popup-title"></h4>
    <div id="{%=id%}_body" class="margin-bottom-10 popup-body">
        </div>

<ul id="{%=id%}ButtonGroup" class="button-group h-popup-buttons even-button-group even-1">
    <li id="{%=id%}Okay_buttonContainer"><a id="{%=id%}Okay" href="javascript:void(0);" class="button success no-margin-bottom h-alert-modal-ok-button" role="button">OK</a><script type="text/javascript">
        (function() {
            function {%=id%}Okay_click(event, data) {
            {%=id%}Popup.hide();
        }
        
                $('#{%=id%}Okay').on('click', {%=id%}Okay_click);
        })();
    </script></li></ul><a href="javascript:void(0);" class="close-reveal-modal" aria-label="Close Modal">&#215;</a><div class="last-modal-focus focus-utility-element" tabindex="0"></div>
</div>
<script type="text/javascript">
        (function() {
            {%=id%}Popup = new SS.Popup.ModalPopup('{%=id%}');
        })();
    </script>