Recreate the CA3028 IC with Discrete Components

To achieve miniaturization, low power consumption, and enhanced reliability in electronic devices, engineers integrate the necessary transistors, resistors, capacitors, and other components into a circuit module. These components are then placed on one or more small substrate pieces and encapsulated in a package to form a compact structure with the desired circuit function—known as an integrated circuit.

No matter how complex an integrated circuit is, it can be broken down into individual components. Depending on the type of integrated circuit, the number of internal components varies. Some circuits may contain billions of transistors within a single package, while others may consist of just a few components.

Datasheets for integrated circuits typically include descriptions of the circuit's architecture, including circuit diagrams for reference. Since the circuit diagrams are provided, one might wonder if it's possible to recreate an integrated circuit from scratch using these diagrams. This is what the article explores.

The article uses the CA3028, a differential amplifier integrated circuit produced by Harris Corporation in the 1990s and later acquired by Intersil. It is now part of Renesas Electronics. The CA3028 is not a complex integrated circuit, making it an ideal choice for testing the performance of discrete component modules.

The datasheet for the CA3028 includes the circuit diagram, which consists of three transistors and three resistors forming a differential amplifier circuit. The circuit is available in CAN and DIP-8 packages, and the design is relatively simple.

The circuit is successfully recreated on a PCB compatible with the DIP-8 package. The resistors are in 0603 size, one transistor is in SOT-23 package, and the differential transistors are in SOT-363 package.

When compared to a DIP-8 integrated circuit, the size difference is minimal.

Soldering the components is relatively easy despite their small size.

After soldering the pins, the assembly is complete.

Compared to a DIP-8 integrated circuit

When installed on a circuit board, this is the single-frequency receiver designed by BD6CR that uses CA3028 as the core component. The size fits perfectly and does not interfere with nearby components. In terms of performance, it works well and may even outperform the original CA3028, though more testing is required for confirmation.