The Fetron's Hybrid Integrated Circuit assembly components (1972)
The Fetron, first invented by Teledyne Semiconductor in 1967, were a family of devices that were direct plug-in solid state compatible replacements for applications that previously used pentode and twin triode vacuum tubes.
Glass Vacuum tubes were highly unreliable and used a lot of electricity, and produced a lot of heat. Fetrons offered the reliability and low power benefits of the newly available solid state technology. Teledyne Semiconductors, and Western Electric, would both create their own versions of a solid state tube replacement device that would mimic the shape and function of an electron tube.
Fetrons came in metal cannister style IC packages. Inside the sealed cannister was a hybrid integrated circuit, manufactured using thick-film technology, with discrete electronic components soldered to a ceramic substrate, including Junction field-effect transistors (JFET).
Glass Vacuum tubes were highly unreliable and used a lot of electricity, and produced a lot of heat. Fetrons offered the reliability and low power benefits of the newly available solid state technology. Teledyne Semiconductors, and Western Electric, would both create their own versions of a solid state tube replacement device that would mimic the shape and function of an electron tube.
Fetrons came in metal cannister style IC packages. Inside the sealed cannister was a hybrid integrated circuit, manufactured using thick-film technology, with discrete electronic components soldered to a ceramic substrate, including Junction field-effect transistors (JFET).
The process of assembling a Fetron started with a square piece of clean substrate that is then applied a conductive film, then a circuit is etched, and chips are attached. The completed circuit is then soldered to the header and gold wires are connected from the circuit to the posts. Last, the header is hermetically sealed with a nickel plated cap.
Pads around the circuit substrate would have bonded gold wires that lead to the socket pins that would extended out the bottom of the canister. The pins for each Fentron were exact pattern matches to the old socket locations of the vacuum tube they were replacing.
By 1972, several hundred thousand FETRONS had been commercially produced and were being used mostly in Telecommunications systems such as Telephone carrier equipment.
Western Electric also produced their own version of a Fetron, called a solid-state Hybrid Integrated Network (HIN). HIN devices had the sole purpose to replace vacuum tubes with discrete solid state components strictly for use in their Bell System telephone switching stations. HIN devices used discrete components assemble inside a metal canister.
Teledyne Semiconductor's Fetrons were also offered as kits to convert some vacuum tubes to solid-state technology for lab equipment such as the Hewlett Packard Model 400 Voltmeters, Heathkit IM-18 Voltmeters, and the Tektronix CA Oscilloscopes.
Vacuum tubes and transitionary type devices like the Fetron, would both be replaced over time by the use of monolithic Integrated Circuit chips.
Pads around the circuit substrate would have bonded gold wires that lead to the socket pins that would extended out the bottom of the canister. The pins for each Fentron were exact pattern matches to the old socket locations of the vacuum tube they were replacing.
By 1972, several hundred thousand FETRONS had been commercially produced and were being used mostly in Telecommunications systems such as Telephone carrier equipment.
Western Electric also produced their own version of a Fetron, called a solid-state Hybrid Integrated Network (HIN). HIN devices had the sole purpose to replace vacuum tubes with discrete solid state components strictly for use in their Bell System telephone switching stations. HIN devices used discrete components assemble inside a metal canister.
Teledyne Semiconductor's Fetrons were also offered as kits to convert some vacuum tubes to solid-state technology for lab equipment such as the Hewlett Packard Model 400 Voltmeters, Heathkit IM-18 Voltmeters, and the Tektronix CA Oscilloscopes.
Vacuum tubes and transitionary type devices like the Fetron, would both be replaced over time by the use of monolithic Integrated Circuit chips.