These synchronous, presettable counters feature an inter- nal carry look-ahead for application in high-speed counting designs. The DM74LSA and. µç×ÓÆ÷¼þ²É¹º½Ì¨£ IC×ÊÁÏ²éÑ¯ÍøÕ¾£º µç×Ó¹ ¤³Ì¼ÊõÂÛ£º / 4 位二进制同步计数器（异步. 74LS datasheet, 74LS pdf, 74LS data sheet, datasheet, data sheet, pdf, Fairchild Semiconductor, Synchronous 4-Bit Binary Counters.
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Finally, you should not count on TTL outputs driving high, as you have shown.
Without this buffering, your switch should not work on a button push, only on a release. I added a 0. You can often get away with less, but as you’ve just learned, insufficient decoupling can have weird symptoms.
I’d reduce that down to something in the nF to 1uF range. Whenever I press the clock button I get all of the leds on except maybe one or two, with some flashing during the button press.
I switched the LEDs around xatasheet connected their input to 5V and their ground to the output pins. Home Questions Tags Users Unanswered. Sign up using Email and Password.
4-bit Synchronous Counter with Asynchronous Clear
N 4-bit counter not counting properly – Electrical Engineering Stack Exchange
WhatRoughBeast 49k 2 28 Also, have you added a 0. That’s probably causing as much trouble as no debounce was. Okay I wired 7,9, and 10 together and then connected them to a 1K resistor to 5V.
You may object that this will provide LEDs which are on when the output is low, and off when the outputs are high, which is confusing.
(PDF) 74161 Datasheet download
Sign up using Facebook. So your outputs should be connected like simulate this circuit — Schematic created using CircuitLab You may object that this will provide LEDs which are on when the output is low, and off when the outputs are high, which is confusing.
74LS161 Synchronous 4-Bit Counter
Email Required, but never shown. I’m still getting the same effect. TTL works much better pulling loads down. Then I used a pullup resistor for the clear switch.
For a circuit board with a ground plane, the usual kc is at least one cap per 5 ICs. I have added a debounce circuit, but still to avail. So your outputs should be connected like. Since you already need one section of aand there are 6 gates per IC, you simply go simulate this circuit.