Operational transconductance amplifiers

Texas instruments has discontinued the DIP-16 version of the LM13700 so they are getting harder to buy. You can use a SOIC to DIP adapter board to fit a SOIC-16 LM13700M/LM13700MX chip into a DIP-16 footprint. Manufacturers XINLUDA and HGSEMI still make 13700 chips in a DIP-16 package.

Through-hole

SMD