Generation of triangle wave at 15KHz frequency
Simple triangle-wave generator using two op-amps.  One op-amp is configured as a Schmitt  trigger, other op-amp is an integrator.  You mention 5V, so I'll include the bias network needed for single-supply operation.  Note that you have to use op-amps with rail-to-rail inputs AND outputs.







simulate this circuit &ndash; Schematic created using CircuitLab

Component values are NOT necessarily correct: R5 &amp; C2 control the frequency.  The ratio of R3 &amp; R4 control the amplitude of the triangle wave - this also affects frequency.