Catalog > Semiconductors > Integrated Circuits PSB8591 Integrated Circuit DTMF Circuit - Dual Tone Multi-frequency Generator 20pin Dip Part No: PSB8591 58.65 ZAR inc for 1 Each (Quoting) Add to Cart Specifications, Prices & Availability may change without notice. Images are for illustration purposes only. E&OE Specifications Case DIP20 Type SemiConductor Manufacturer Siemens Semiconductors Oper. Temp (°C) Min -20 Oper. Temp (°C) Max. 75 Pinout Equivalence Number 20-97 No. of Pins 20 Surface Mounted Yes/No NO