---

Circuits using only discrete devices

• Isolated dual power supply from 5V
• Telephone LED status indicator
• Music Sound to light converter
• Simple Water operated relay
• LED Voltage Level Indicator
• Basic Relay or Solenoid Driver

Parts or Components in Electronics :

Here are circuits made of Resistors, Capacitors and Inductors which are passive components. Crystals, Thermistors, Varistors, Variable Passive RLC are also Passive Parts.



Electronics Work Bench

Some circuits documented from my design note book are here with the editable schematics.Zeners, Diodes, NPN-PNP Transistors, FET, MOSFET, SCR, Triacs are all discrete active devices. ICs and Hybrid Modules are  made of many discrete and passive  components.


 
FET Current Source and MOSFET

In the Integrated Circuits or ASICs, all parts even passives are derived on the Silicon Wafer. In Hybrid Modules the construction uses SMD or Tiny Chip components interconnected in a small ceramic PCB and Hermetically Sealed if needed.

Parts like Switches, Connectors, Relays and PCBs are ElectroMechanical parts. Nuts, Bolts, Screws, Cabinets and enclosures are Mechanical parts.



Constant Current Source LED Drive

For a Systems Integrator or Control Panel Designer, the Timers, Controllers, PLC which are Electronic Products become Components or Modules along with Contacters, Current Transformers, AC-DC Drives etc.

Simple High speed data switch

Components have to be wired up on boards while designing or testing circuit blocks or concepts. Some examples of these are shown below.
 

---

---

The Breadboard

This is a reusable gadget like a connector, works like an IC base, only that the connectors in this are very long lasting. you can just plug in the components and connect using thick pre-tinned single strand wire. Big pins can ruin the micro sockets and power circuits. Levels of > 24V and > 1500mA and > 350 KHz could be avoided on these boards.

The Electronics Index

General Purpose PCB

This is a PCB that is available is most hobby shops, they are known as "General Purpose Prototyping Board". They have to be soldered and some tracks cut with tool-knife. Power circuits also can be built with wire reinforcements and RF circuits too if you plan the layout first on paper. High Current paths < 5A can be reinforced by thick copper strips and high voltage points < 48V can be isolated by one empty or unused track or island.

A General Purpose board was designed keeping DIP (Dual in Line Package) IC Chips in mind. There are now boards for SMT and may accommodate SMD chips and parts.

Stripboards

Stripboard was the first General Purpose Board, it was the Tag Board for Semiconductor Electronics. There in more cutting tracks and planning needed here.

When you manufacture small numbers of prototypes or custom equipment GP Boards are used in a professional manner. You could also use a CNC PCB Router also called Desktop CNC Mill. Wire Wrap Boards also was a popular in Custom Instrument, Machine or Equipment manufacturing.

Tag Board and Turret Board

These were used in Vacuum Tube or Valve Electronics based Products like Early Radios, Spool Tape Recorders and Audio Hi-Fi Systems. These boards held the large Capacitors and Wire wound resistors that were parts of a Valve Amplifier or demodulator.



Turret Boards have Tinned Copper Pins in place of the Tags. Today these are used in Power Electronics and Mains Electrical Circuits and R&D Prototypes. High Energy circuits, High Voltage and High Current Supplies have some parts on these boards. Even Heat Dissipating Semiconductors can be mounted with proper Heatsinks.