The LM13700 is basically 2 CA3080 ICs put together in a larger IC, with a couple buffer circuits added in for good measure. From the datasheet:
"The LM13700 series consists of two current controlled transconductance amplifiers, each with differential inputs and a push-pull output. The two amplifiers share common supplies but otherwise operate independently. Linearizing diodes are provided at the inputs to reduce distortion and allow higher input levels..." "...High impedance buffers are provided which are especially designed to complement the dynamic range of the amplifiers."
This is used in the GuitarPCB SWAH, as well as the MoRC compressor, which originally used the CA3080 (now obsolete). It is probably now the most common "Operational Transconductance Amplifier" (OTA) in the DIY pedal world.
Current stock is National Semiconductor, but equivalent brand-name parts may be stocked in the future.
|LM13700 Dual OTA |
Download Datasheet PDF