Four Channel On Off Control Circuit, Feature : Easy To Install

Listing ID #964119

We are a noted Manufacturer and Supplier of Four Channel On/Off Control Circuit in India. This four-channel control uses only one D type latch IC1, and some associated circuitry to control four different gadgets. To control more devices, identical circuits, in multiples, can be used. IC1 consists of eight latches, out of which four are used here. The circuit incorporates the following features :

• Individual ‘on/off’ control for all channels.
• Emergency ‘off’ control for all channels.
• Immediate ‘on’ control for all channels
• LED indication for ‘on’ channels
• Optional push-to-on buttons or tectile switches.  

About the Circuit :

• When one presses the ‘on’ switch (S1) of channel-1, a logic low is applied to data input D0 (pin3). The same level appears on the data output Q0 (pin2). Because latch enable pin LE (pin11, active high) is connected to +5V, and the output enable OE (pin1, active low) is pulled down using resistor R9. At the same time, Q0 output is fed back to D0 input, which thus keeps the common junction of D0 and Q0 at low level, even after releasing ‘S1’. This low level is applied to the base of transistor T1 through diode D9 to turn it on, and relay RL1 activated. LED D13 glows indicate that channel-1 is ‘on’. The other channels can also be switched on, as desired, in a similar manner.
• To switch of channel-1, ‘off’ switch ‘S5’ of channel-1 is pressed to apply logic high to junction of D0 and Q0. Because of the feedback from Q0 to D0 junction remains high even after releasing the switch S5. As a result, relay RL1 is deactivated and LED D13 also goes off.
• In the case of emergency, press the emergency off switch ‘S9’ to disable all the outputs of IC1. The outputs of IC1 are in high impedence state, all the relays gets deactivated.
• If all the channels are to be switched on simultaneously, a ‘low’ logic level is applied via diodes D9 through D12 to data input D0 to D3 by pressing S10 to activate all the relays.
• ON/OFF four channels, with ‘All ON’ and ‘All OFF’ facility