74LSN from Fairchild Semiconductor. Find the PDF Datasheet, Specifications and Distributor Information. 74LSN Datasheet, 74LSN PDF, 74LSN Data sheet, 74LSN manual, 74LSN pdf, 74LSN, datenblatt, Electronics 74LSN, alldatasheet. These 8-bit shift registers feature gated serial inputs and an asynchronous clear. A low logic level at either input inhibits entry of the new data, and resets the first.
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Through a few of my previous articles I have tried to cover the working principles of a couple of versatile ICs like the and That’s a good guess, but the recent oscilloscope pictures posted after your answer looks pretty clean.
Sign up using Facebook. The length of your clock wire might be a factor in this. Sign up or log in Sign up datasheeg Google. You are probably 74lw164n multiple pulses instead of just one. Introduction Through a few of my previous articles I have tried to cover the working principles of a couple of versatile ICs like the and Then I send a clock pulse from the Raspberry Pi go high for ms then go low.
74LSN Datasheet – Shift Register from
Unlike ordinary CMOS ICs which has also been discussed in many of my previous articlesthe above ICs are equipped with many different built-in features which may be accessed or activated by just applying the appropriate logic inputs or components to their 74sl164n pin-outs.
Sign up using Email and Password. That’s pretty far fetched, given the frequencies involved. Now suppose if through a simple wiring pins 1 and 2 are configured in such a way that when the last pin 13 of the IC goes high while sequencing serially, it grounds the serial input 1 and 2.
Output mode is push-pull with at least 2mA sink capability. For example if the pin — outs 1 and 2 are permanently connected to the positive supply and the reset pin is joined to the last output of dattasheet IC pin 13then, as discussed earlier, once all the outputs become high the last pin 13 instantly resets the whole circuit, shutting the whole array of outputs, and the cycle repeats.
The register was clocking multiple times because the clock signal wasn’t enough clean. I took some photos of the scope, the first is the clock from the GPIO without nothing and the second is the clock connected to the register. Thus exceeding operating conditions, all bets are off.
This opposite sequencing also takes place in accordance to the rising pulse of the input clocks. If your wires are already short, then consider adding a signal integrity resistor ohms in series with the clock pin as close to the driver as possible.
74LS164 – 8-Bit Shift Register Ser In/Para Out
The extreme top left pin from the printed side is the first pin in the order, and the pin just opposite to it on the other row is the last or the 14 th pin.
Hasn’t ever happened to me. You should test with the FETs in place.
SN74LSN3 Datasheet(PDF) – TI store
Do you have an oscilloscope? You have an unexplained 1V offset. You likely 74os164n reflections on your clock line, causing it to be treated as multiple clock pulses. Thanks for all your advices and suggestions, have a nice day. The thresholds are 0. Similarly the IC requires only an external clock signal to make its outputs swing into action and produce interesting logic sequences.
Referring to the figure on the left we see that externally it looks just like an ordinary pin dual in-line chip.
You might simply have a logic level compatibility issue between Pi and the LS inputs. The serial inputs pin 1 and 2 of the IC has a special purpose of resetting the above procedure in an interesting pattern. Or, the pulse has a ragged edge s and the is actually clocking several times. Referring to the figure on the left we see that externally it looks just like an ordinary pin dual in-line chip. Might be missing decoupling capacitors too.
Hopefully you will get to see another article pretty soon, which will explain the practical utility of this wonderful IC.