Hello fellow "desigers"
I am strugling to use the output of the DAC port on a PICAXE18M2. I am trying to use that signal in the standard 32 steps en feed as in input signal to LM3914 LEDbar driver. It steps nicely from about 0.15V to 4.7 V which is perfect for me.
The DAC-signal itself is to low powered to drive the LM3914 straight away so i tried to use an OpAmp with single powersupply like LM324 or LM339. I can't use dual power because there is no negative power available.
I am using the LM324 as a gain follower but as soon i connect the DAC output to the non inverting input of the LM324 the output of the OpAmp jumps to half level of the power powersupply. For example powersupply is 5V then output from the Opamp will b 2.5V
Has anyone of you a good working solution for this problem ??? Maybe an electric schematic ??
Excuses for my horrable english
I am strugling to use the output of the DAC port on a PICAXE18M2. I am trying to use that signal in the standard 32 steps en feed as in input signal to LM3914 LEDbar driver. It steps nicely from about 0.15V to 4.7 V which is perfect for me.
The DAC-signal itself is to low powered to drive the LM3914 straight away so i tried to use an OpAmp with single powersupply like LM324 or LM339. I can't use dual power because there is no negative power available.
I am using the LM324 as a gain follower but as soon i connect the DAC output to the non inverting input of the LM324 the output of the OpAmp jumps to half level of the power powersupply. For example powersupply is 5V then output from the Opamp will b 2.5V
Has anyone of you a good working solution for this problem ??? Maybe an electric schematic ??
Excuses for my horrable english