Intersil_ICL8038
The ICL8038 waveform generator was an Integrated circuit by Intersil designed to generate sine, square and triangular waveforms,[1] based on bipolar monolithic technology involving Schottky barrier diodes.[2] ICL8038 was a voltage-controlled oscillator[3]: 434 capable of producing frequencies between a millihertz and 100 kHz.,[4]: 2 some specimens capable of reaching 300 kHz.[4]: 1 The device has been discontinued by Intersil in 2002.[1][4]: 1
Triangular waves were produced by charging and discharging a capacitor with constant currents. The triangular waves were converted to sine waves involving a non-linear network.[4]: 4 The output frequency was set either by resistors or the external control voltage.[4]: 6 The temperature drift could be optimized to less than 250ppm/°C by combining it with a PLL.[4]: 1
Maxim designed a copy of the ICL8038 and marketed it as the MAX038. Both devices have since been discontinued.[citation needed]