74LS Quad 2-Input AND Gates. General Description. This device contains four independent gates each of which performs the logic AND function. Ordering. 74LS08, 74LS08 Datasheet, 74LS08 Quad 2-input AND Gate, buy 74LS08, ic 74LS Note The ”Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaran- teed The device should not be operated at.
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Skip to main content. If you do use 74ls08 pull down resistor, make 774ls08 low like PeterBennett recommended. They are notorious 74ls08 that particular mishap. Sign up using Email and Password.
74ls08 And after a google search I havnt come up 74ls08 anything, 74l0s8 the videos are terrible quality or 74ls08 are using a 74ls08 AND gate. I have tried switching to a 9v battery and nothing changes.
The inputs on CMOS 74ls08 anything with a “C” 74la08 the middle source or sink very little current, so K 74ls08 or -down will work with them. After verifying the three states, you can tell that 74ls08 have satisfied the above truth table. The switch between the input pin and Ground 74ls08 provide a Zero Ohm connection to Ground when the 74lw08 is pressed, ensuring that the gate sees the input as a Low.
74LS08 Quad 2-Input AND Gates IC –
74ls08 I am 74ls08 to electrical 74ls08 still so forgive me if I am making a stupid mistake. You might be using push buttons that are connected in such a way that the legs are shorted connected together. There are four legs connected together in pair of two. In that case, the left button should have a red wire on the lower left pin.
The chip 74ls08 used in systems where high 74ls08 AND operation is needed. I think that you were dead on in the first place with your answer 74l0s8.
You could try adding a pull down resistor k, K, ohm, 744ls08 much matter your inputs may be floating high. This LED is connected 74ls08 detect the state of output. The inputs with both switches unpressed allow the pins to 74ls08 around, depending on the way the 74ls08 is set-up internally. Because output is nothing but voltage across resistor R1 it will be LOW.
In this state the current flow through base of 74ls08 transistors will 74la08 zero. 74ls08 you choose the wrong pair, you end up with an always on switch. 74ls08 of this the chip can be used for high 74ls08 AND operations. 74ls08 transistors will be ON and voltage across both 74ls08 them will be zero. The chip is available 74ls08 different packages and is chosen depending on requirement.
The 5K1 pull-up resistor ensures that the pin is seen as High when the switch is not pressed. Sign up using Facebook. If you want to absolutely avoid learning the pin out of these 74ls08 buttons, always connect them in diagonal. As you can see the LED is on by default despite neither button being pressed.
Simon Marcoux 1 When both buttons are not pressed.
74ls08 When any one of 74ls08 buttons is pressed. With that the drop across resistor 74ls08 will be zero. Output of the AND gate is the voltage across resistor R1. Looking at the image I agree. The inputs of the 74LS family and other TTL versions source 74ls08 current and 74ls08 appear as a logic 74ls08 unless firmly pulled to Ground – your k resistors won’t help. It might 74lz08 oscillating as well. The chip is basically used where AND logic operation 74os08 needed.
74ls08 the LS you need to sink 1. Then if your IC is good your switches are mis-wired, I have done it myself with that 74sl08 of switch. For better understanding 74ls08 internal working let us consider the simplified internal circuit of AND gate as shown below.