16 Step Sequencer Quantized Vari-Clock Module


Posted on Feb 5, 2014

A mechanism by which a normal pot could be used as a digitized pot since I need each pot`s setting to be converted to a number between 0 and 15. I use that information to determine the duration for each step. I accomplished this by designing an analog to digital convertor that could take a pot`s position and convert it to a number between 0 and 15 relatively quickly (within 300 microseconds or so).


16 Step Sequencer Quantized Vari-Clock Module
Click here to download the full size of the above Circuit.

The A to D convertor is the type that uses a D to A convertor to create a stepped ramp voltage to which the input is compared. When the stepped voltage output of the D to A convertor is a few millivolts above the current input level the current count from the D to A convertor is clocked into a latch. The latched output is the D (digital code) in this A to D convertor. The circuitry is described below. The A to D convertor is realized by U1, U2, U3 and U4. U2 is a CD40193 binary counter whose outputs are connected to the classic R/2R network (made up of R6, R7, R12, R16, R15, R18, R19, R20 and R22) which converts the binary output to a voltage level which is linearly related to the binary count (I refer to this as the D to A element of the A to D convertor). R23 (470K to +12V) causes the output of the R/2R ladder to be positively biased a bit. This is to allow sensing of zero volts by the A to D convertor. The counter is clocked by U1-A, C17 and R26 which are wired as a simple phase shift oscillator. The CD40193 is wired to count upward and thus the output of the R/2R ladder (D to A) is a positive going stepped ramp wave whose voltage levels correspond with the binary output of the counter. U3-A buffers the R/2R network output and applies it to the non-inverting input of U3-B via 10K resistor R17. U3-B`s inverting input is connected to the level shifted input voltage (Point DV). Point DV connects to the common I/O point on...




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

telephone line loger
LED Flasher Using 555 IC
Metal Detector Circuits Schematic Diagram
Automatic Water Tank FillerCircuit Circuit
booster radio fm schematic circuit
EM4294 13.56MHz Crypto Analogue Front End Circuit For High Secure RFID Communication
Bias supply powers low power Geiger Mueller tube
Multivibrator



Top