Faster, cheaper and lighter electronic devices continue to fuel the need for smaller electronic components. Because of this need for miniaturisation, designers are now developing ultra-small inductors that are efficient and enhance the life of electronic products.
By Shruti Mishra
An inductor is a basic, passive electronic component that caters to many sectors including consumer electronics, telecommunications, military and automobiles. Inductors are widely used for high power applications, noise suppression, signal processing and voltage stabilisation. As it is impossible for a single inductor to perform all these functions, various types of inductors are designed and used for these diverse applications.
A choke is a type of inductor that is used for choking off or blocking high frequency or alternating current (AC) from entering an environment where low frequency or direct current (DC) is required. Coils of a relay also act as an inductor and control the flow of current in it. Inductors, when used in combination with capacitors, act as a filter and separate the signals of different frequencies. That helps to make tuned circuits, which are used in radio and TV broadcasting. Other types of inductors include transformers, ferrite beads and power inductors.
Technological advancements
The shrinking motherboards of the next generation electronic devices are pushing inductor makers to weave improved performances into ever-tinier packages. Most technological developments in inductors these days are happening around size reduction and are yielding some impressive results.
One of them is the thick- or thin-film construction technique that replaces the age old copper wire winding that was earlier used as an inductor. This technique not only significantly reduces the physical size and weight of inductors but also offers drastic improvements in key parameters such as Q factor, self-resonant frequency, tolerance and inductance.
Power chokes, used largely in line filters, power supplies and DC/DC converters, are also moulded in a mini form to serve the need for smaller sizes. Mini moulded chokes are mostly used in smartphones and tablets for sleeker designs, improved battery life and power management.
Another tech advancement in the handheld devices category is the development of 2-in-1 inductor array products, which enable more effective use of the limited circuit space.
Some obstacles…
Domestic manufacture of all types of inductors is facing an acute setback due to unavailability and constant variation in the prices of raw materials, and there is a great reliance on imported inductors at present. Anil Batra, managing director, Indian Technological Products Pvt Ltd, says, “Relays (or inductors) are made in a highly automated production facility, wherein coil winding, assembly and testing are all automated. There is intense competition today from imported relays, as the Indian production base is not able to take advantage of the economies of scale. Like any other industry, this industry is also totally driven by price; local companies are relying heavily on imports because they are getting an unrestricted supply of good quality relays at a relatively low cost.”
However, he points out the risk factor when the buyer bases procurements primarily on price. “There are some manufacturers in China who keep on diluting the specifications if the customer continues asking for a lower price. Therefore, it is important to base the purchase on consistent quality as well as on price,” he adds.
The latest products available in the market
Model: TR5v, Manufacturer: Indian Technological Products Pvt Ltd
This telecom relay is specifically designed for thermostat modems, computer peripherals, video recording and security applications. Its terminals are arranged in grid patterns and are suitable for compact and high density mounting.
Key features
- Dimensions (LxWxH): 12.4mm x 7.4mm x 10mm
- Maximum operating current: 2A
- Maximum operating voltage: 120V AC
- Ambient temperature: -30°C to 85°C
- Mechanical life: 10,000,000 mins
Contact: www.itpindia.com
Model: IHLM-2525CZ-01, Manufacturer: Vishay Intertechnology
This inductor is designed to handle high current spikes without saturation. Its encapsulated body offers improved environmental protection and moisture resistance. The inductor can be used in desktop or server applications, battery-powered devices and DC-DC converters in distributed power systems.
Key features
- Inductance: 1.0μH
- Inductance tolerance: ±20 per cent
- Operating temperature range: -55°C to 125°C
- Operating voltage: 75V
- Frequency range: Up to 5.0MHz
Contact: www.vishay.com
Model: G5v – 1, Manufacturer: Omron
This is an ultra-miniaturised, highly sensitive, low-signal relay for signal circuits. Its fully sealed construction offers complete protection against harsh climates. Telecommunication equipment, audio-visual products, security equipment and automation equipment are some of its application areas.
Key features
- Dimensions (LxWxH): 12.5mm x 7.5mm x 10mm
- Switching power: 1mA to 1A
- Ambient operating temperature: -40°C to 70°C
- Ambient operating humidity: 5 per cent to
- 85 per cent
- Weight: 2g approx.
Contact: www.omron.com
