Anormal low current from JK flip flop ici at toggle mode


I am building a prototype of a balance indicator to prevent farm quadbike to roll on steep hills. I am using an arduino pro mini and 2 sets of assignable strips of 8 leds (NeoPixel Stick - 8 x 5050 RGB LED with Integrated Drivers : ID 1426 : $5.95 : Adafruit Industries, Unique & fun DIY electronics and kits) and a gyro-accelerometer sensor. To power it, I am using the farm motor bike battery (12V). To switch the arduino on and off, I am using a momentary push button switch (NO, NC, C pins) and a JK flip flop ic (4027 dual jk flip flop cmos ic zc 4027). I have my 12V from the battery connected to the flip flop on vcc, j,k and the ground to vss,set and reset. My momentary switch give normally close ground to the clock pin and 12v when I press it. I use the flip flop as toggle mode with my switch as a clock. Next, from the ic, between the output Q and the ground, I have linked a 1F capacitor, my set of leds and the arduino in parallel. The capacitor is to prevent a damaging pike for the leds strip. I have tested it, I have the expected 12V after pressing once the switch and 0V after pressing it again. But when it is on 12V and the arduino and the leds should be running, the current is very low, too low to run the arduino and the leds. Could someone please help me ? I am lost. I am a student at high school very dedicated to my project. I have tried the device on the 12V battery without the switch and jk flip flop, it works fine.

Thank you very much,



Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Can you please post a copy of your sketch, using code tags?
They are made with the </> icon in the reply Menu.
See section 7,148850.0.html

If you are trying to power the arduino and LEDs from the output of the flipflop, then soory it is not possible.
If you look up the data for the IC it will tell you the maximum output current that the IC can supply.

Tom… :slight_smile:

The max output current of that FF is 3mA.
I suggest high-side switching of the load with a P-channel mosfet.
Almost any medium power P-channel fet will do.
1k resistor between FF-out and gate.
Source to +12volt, Drain to load (Arduino/LED/etc).
100k resistor between source and gate.