shedboy71

The 4067 was one of the IC’s that I wanted to connect up to various microcontrollers as it looke dextremely useful, here is a quick description from one of the datasheets with an overview of the functionality

The HEF4067B is a 16-channel analog multiplexer/demultiplexer with four address inputs (A0 to A3), an active LOW enable input (E), sixteen independent inputs/outputs (Y0 to Y15) and a common input/output (Z). The device contains sixteen bidirectional analog switches, each with one side connected to an independent input/output (Y0 to Y15) and the other side connected to the common input/output (Z). With E LOW, one of the sixteen switches is selected (low-impedance ON-state) by A0 to A3. All unselected switches are in the high-impedance OFF-state. With E HIGH all switches are in the high-impedance OFF-state, independent of A0 to A3. The analog inputs/outputs (Y0 to Y15 and Z) can swing between VDD as a positive limit and VSS as a negative limit. VDD to VSS may not exceed 15 V.

Here is the pinout of the 4067

You can see depending on the state of pins S0 – S3 determines the output channel pin that is used. So if S0 to S3 are 0 then Channel 0 which is Pin 9 is selected

Schematic

Here is a schematic, in this example we only connected 1 LEDs and resistors but its easy to add another 8 from X8 to X15

Code

The code example only uses 8 LEDs

[cpp]

const int channel[] = {15, 2, 0, 4};

//the output pin – mux input
const int outputPin = 16;

void setup()
{
pinMode(15, OUTPUT);
pinMode(2, OUTPUT);
pinMode(0, OUTPUT);
pinMode(4, OUTPUT);
pinMode(16, OUTPUT);
}

void loop()
{
//iterate through the first 8 channels of the multiplexer (change to 16 if you
//have 16 LEDs or outputs connected)
for (int muxChannel = 0; muxChannel < 8; muxChannel++)
{
//set the channel pins based on the channel you want
//LED on – high – 100 milliseconds delay
muxWrite(muxChannel);
digitalWrite(outputPin,HIGH);
delay(100);
}
}

void muxWrite(int whichChannel)
{
for (int inputPin = 0; inputPin < 4; inputPin++)
{
int pinState = bitRead(whichChannel, inputPin);
// turn the pin on or off:
digitalWrite(channel[inputPin],pinState);
}
}

[/cpp]

Links

Free shipping CD4067BE CD4067 DIP24(5pcs/lot)

The HCF4051 device is a monolithic integrated circuit fabricated in MOS (metal oxide semiconductor) technology available in SO-16 and PDIP-16 packages.

The HCF4051 analog multiplexer/demultiplexer is a digitally controlled analog switch having low ON impedance and very low OFF leakage current. This multiplexer circuit dissipates extremely low quiescent power over the full VDD- VSSand VDD- VEEsupply voltage range, independent of the logic state of the control signals.

This device is a single 8-channel multiplexer having three binary control inputs, A, B, and C, and an inhibit input. The three binary signals select 1 of 8 channels to be turned on, and connect one of the 8 inputs to the output. When a logic “1” is present at the inhibit input terminal all channels are off.

Here is a pinout of the 4051

Lets look at the truth table of the 4051 which will show how this works

Now lets have an example, we want to flash an LED on Channel AO which is Pin 13 of the IC, in this case A0, A1 and A2 all have to be a logic 0. So with our micro we can make the pins that we connect to A0, A1 and A2 all low and that will activate channel A0. In our example we have the following wiring

A0 – LOLIN32 2
A1  – LOLIN32 0
A2 – LOLIN32 4

INH or Enable is tied to 0v

In the schematic below we show 1 resistor and LED only, our test board had 8 sets of resistors and LEDs

Code

The code is actually adapted from the 4067 example, I saw a couple of whacky code examples which to be honest i couldn’t get working. This example will cycle through all 8 channels one at a time.

[cpp]

const int channel[] = {2, 0, 4};
//the output pin – mux input
const int outputPin = 15;

void setup()
{
pinMode(2, OUTPUT);
pinMode(0, OUTPUT);
pinMode(4, OUTPUT);
pinMode(15, OUTPUT);
}

void loop()
{
//iterate through all 8 channels of the multiplexer
for (int muxChannel = 0; muxChannel < 8; muxChannel++)
{
//set the channel pins based on the channel you want
//LED on – high – 1000 milliseconds delay
muxWrite(muxChannel);
digitalWrite(outputPin,HIGH);
delay(1000);
}
}

void muxWrite(int whichChannel)
{
for (int inputPin = 0; inputPin < 3; inputPin++)
{
int pinState = bitRead(whichChannel, inputPin);
// turn the pin on or off:
digitalWrite(channel[inputPin],pinState);
}
}

[/cpp]

Links

10PCS CD4051BE DIP16 CD4051 DIP new and original IC free shipping