Search found 1590 matches

by dyarker
Sun Apr 11, 2021 5:07 am
Forum: Computer Programming
Topic: 74HC595A Shift Register Outputs Low Level?
Replies: 2
Views: 89

Re: 74HC595A Shift Register Outputs Low Level?

4 days. It was output enable?
by dyarker
Sat Apr 10, 2021 9:54 pm
Forum: General Discussion
Topic: Crappy Headphone wires.......
Replies: 7
Views: 2523

Re: Crappy Headphone wires.......

CAT-5 or CAT-6 patch cords are of stranded wire.
by dyarker
Wed Apr 07, 2021 8:21 am
Forum: Computer Programming
Topic: 74HC595A Shift Register Outputs Low Level?
Replies: 2
Views: 89

Re: 74HC595A Shift Register Outputs Low Level?

You need a better spec sheet, like - https://www.onsemi.com/pdf/datasheet/mc74hc595a-d.pdf (not from TI, but is for the "A" part (74HC585 A )) Also needed - A schematic diagram of your circuit. My first EWAG based on limited info provided is OUTPUT ENABLE pin needs to be pulled up. side comment - Th...
by dyarker
Tue Mar 23, 2021 5:38 pm
Forum: General Discussion
Topic: 555 Timer ic question please
Replies: 9
Views: 250

Re: 555 Timer ic question please

agreed!
by dyarker
Mon Mar 22, 2021 11:10 pm
Forum: General Discussion
Topic: 555 Timer ic question please
Replies: 9
Views: 250

Re: 555 Timer ic question please

I asked "Do you want re-triggerable?" He answered "Yes". Which is wrong based on rest of answer. "Re-trigger" does not ignore triggers during time period. You said the "yes" was to the "Ignore"; but that was not the question! Please learn to READ before butting in! Back to post 1 - regardless of if ...
by dyarker
Mon Mar 22, 2021 5:59 pm
Forum: General Discussion
Topic: 555 Timer ic question please
Replies: 9
Views: 250

Re: 555 Timer ic question please

additional triggers do not exceed the Delay Time Then the answer is NO. You want additional triggers during the delay ignored till after the delay, Then another trigger starts a new delay. "Re-trigger" means the output could stay on forever, as long as triggers happen before the delay time since th...
by dyarker
Mon Mar 22, 2021 9:21 am
Forum: General Discussion
Topic: 555 Timer ic question please
Replies: 9
Views: 250

Re: 555 Timer ic question please

It can be either way. Re-triggerable takes a couple transistors; one to discharge the timing capacitor to start the time over again.

Do you want re-triggerable?

Cheers,
by dyarker
Thu Mar 18, 2021 8:21 pm
Forum: General Discussion
Topic: Adafruit 1.2" led display
Replies: 11
Views: 610

Re: Adafruit 1.2" led display

Haklesup, It says that it has been discontinued.
How would he know? Requires reading.
by dyarker
Mon Mar 01, 2021 8:19 pm
Forum: General Discussion
Topic: 555 timer missing pin
Replies: 4
Views: 318

Re: 555 timer missing pin

Pin 6 would be the pin for the connection missing a pin number.

Pin 5 is also not shown, but is the junction of internal voltage divider, so does not need to be used in this case.

Cheers,
by dyarker
Mon Nov 02, 2020 8:34 pm
Forum: General Discussion
Topic: Power Supply for mains circuit _linear or switch mode
Replies: 7
Views: 1195

Re: Power Supply for mains circuit _linear or switch mode

The load is 15 ohms at 120 Volts and 12 amps DC.
Does not compute!

120V / 12A = 10 Ohms

Or, if the 15 Ohms is correct, then 12Amps is wrong; like JWax said.
by dyarker
Mon Nov 02, 2020 2:13 pm
Forum: General Discussion
Topic: Power Supply for mains circuit _linear or switch mode
Replies: 7
Views: 1195

Re: Power Supply for mains circuit _linear or switch mode

I have never of anything needing 110VDC at 12 Amps. (probably why no vendor makes one)

And not safe unless isolated from mains.

What is the load?
by dyarker
Mon Nov 02, 2020 10:11 am
Forum: General Discussion
Topic: Power Supply for mains circuit _linear or switch mode
Replies: 7
Views: 1195

Re: Power Supply for mains circuit _linear or switch mode

How are you regulating the output to 110VDC? The peak of 110VAC is 155V. At no load that is what the filtered DC will be. As load current increases, output ripple voltage increases as the filter capacitor supplies the current between the input voltage peaks. The input current is zero till the input ...
by dyarker
Thu Sep 10, 2020 7:39 am
Forum: General Discussion
Topic: ADR421 Vref IC Low Short-Circuit Current!
Replies: 10
Views: 1590

Re: ADR421 Vref IC Low Short-Circuit Current!

Not getting 10mA (max) into a load is a problem. It looks like IC fails in this respect.

Getting a smaller short circuit current is a good thing. Why are you worried that? When output voltage is forced to zero (by short) the IC probably limits the current so it does not destroy itself.
by dyarker
Tue Sep 08, 2020 2:17 pm
Forum: General Discussion
Topic: ADR421 Vref IC Low Short-Circuit Current!
Replies: 10
Views: 1590

Re: ADR421 Vref IC Low Short-Circuit Current!

Where are you seeing 27mA in the spec.
Last item in specs for each part number. In this case on page 5 of 24. And resolved subject line problem in post 2.
by dyarker
Mon Sep 07, 2020 8:11 pm
Forum: General Discussion
Topic: ADR421 Vref IC Low Short-Circuit Current!
Replies: 10
Views: 1590

Re: ADR421 Vref IC Low Short-Circuit Current!

Now I missed a line on spec sheet - Load Regulation, Conditions column; which shows 0ma to 10mA.

Where did you get the IC? Discount places sell parts that failed some test but still function.