TT Electronics - Welwyn Components

Welwyn Components are a designer and manufacturer of a full portfolio of resistor technologies, serving the industrial, defence, automotive and medical sectors.

With a fully comprehensive product offering, Welwyn offer an ohmic value range spanning 18 decades, and many innovations in the field of high power steel resistors, safety qualified fusing resistors and high energy surge tolerant parts.

We stock the full range of Welwyn products.

GHVC is the industry’s first high voltage chip resistor which is completely free of Pb and its compounds and therefore is RoHS compliant without exemption.

GHVC is the latest addition to our range of high voltage chip resistor products. It is essentially a variant of HVC designed using green thick-film materials which are completely free of Pb (lead) and its compounds. This allows the product to be RoHS compliant without relying on exemptions which may be withdrawn in the future. Available in three sizes from 1206 to 2512, GHVC has LEVs in the range 1 to 3kV and withstands up to 7kV peak for a 1.2/50µs surge. It is ideal for high voltage sensing and protection in compact power supplies, circuit breakers and medical monitors.

Applications

  • Power supplies
  • Circuit breakers
  • Medical monitor input protection

Market Segments

  • Industrial
  • Medical

Features

  • Free of Pb and its compounds
  • RoHS compliant without exemptions
  • Limiting element voltage up to 3kV
  • Overload voltage up to 4kV
  • Takes 1.2/50µs surge voltage up to 7kV
  • Anti-sulphur terminations standard

Product Documentation

GHVC Datasheet | PDF

Market Segments

  • Industrial
  • Medical

Applications

  • Enclosure heaters for exposed environments
  • Chemical & food processing
  • Sealing & printing
  • Medical humidifier

Features

  • Ultra low profile <2mm
  • Up to 400°C operating temperature
  • Uniform temperature distribution
  • Low thermal mass
  • Single fixing mountable
  • Temperature feedback / limit (custom)

Benefits

  • Low profile allows space-saving integration which is not possible with bulky wirewound or PTC alternatives.
  • Wide area heating is possible with a single element, avoiding the cost of multiple elements or heat spreaders.

Product Documentation

WSHR Datasheet | PDF

Market Segments

  • Industrial
  • Medical

Applications

  • Power supplies
  • DC-DC convertors
  • Motor invertors
  • HVAC systems
  • Lighting drivers

Features

  • High power 5W
  • High stability foil on ceramic
  • Values R002 to R05 at 1% tolerance
  • TCR down to ±30ppm/°C
  • Low temperature rise

Benefits

  • Low ohmic values to R002 minimise power loss.
  • Low TCR improves the temperature stability of the circuit.
  • Metal foil on ceramic technology has better surge tolerance than thick-film, enhancing product reliability.
  • Metal foil on ceramic technology has lower self-heating than thick-film or metal strip, enhancing product reliability.

Product Documentation

MFC Datasheet | PDF

WDBR-UL series is a thick film on steel power resistor with UL recognition. It has been developed based on the existing WDBR product which itself has been successfully used in the field for over ten years. The creepage and clearances and power ratings have been assessed in accordance with the requirements of UL508.

Our Advantage

For circuit designers who need to design UL approved systems containing power resistors in highly compact enclosed assemblies with heatsink-based thermal management, we provide WDBR-UL which provides a far lower volume solution than competing encased wirewound products and a faster route to safety certification.

Benefits

  • Low profile allows space-saving integration which is not possible with bulky wirewound alternatives
  • UL recognition eases the compliance burden for UL approved end uses

Market Segments

  • Industrial

Applications

  • Motor drive invertors
  • Dynamic braking, inrush current limiting, snubber
  • Electronic assembly heater Element
  • Over-voltage protection in wind turbines

Features

  • UL508 certified – UL file E238661
  • Ultra-low profile – thickness <2mm
  • Rated power up to 1.4kW
  • Overload power up to 13kW
  • Isolation to 2.5kV
  • 12R to 150R in 5 size options

Product Documentation

Datasheet | PDF
Press Release | PDF
Fast Facts | PDF
CR-HR-series-welwyn

CR series is a thick film chip resistor designed for high reliability applications. Until now there have been four standard sizes for solder terminations and CR0603 adds a fifth, smaller size to the range. With the same value range 1R0 to 10M, CR0603 provides a high reliability component in compact circuits where footprint is critical.

Market Segments:

  • Aerospace
  • Military
  • Medical
  • Industrial
  • Communications

Applications:

  • Sub-sea repeaters
  • Mainframe systems
  • Hi-rel systems

Features:

  • CECC40401 release option
  • High temperature and overload 100% screening available
  • Tolerance down to 0.1%
  • Gold wire bond or solder terminations
  • Zero-ohm link available

Benefits:

  • Screened resistor enhances reliability and reduces field failures.
  • Thick-film element has higher surge tolerance than thin-film, also improving reliability.
CR-HR-series-welwyn

HR series is a thick film chip resistor designed for high ohmic value applications. Until now there have been two standard sizes for solder terminations and HR0603 adds a third, smaller size to the range. With the value range 10M to 20G, HR0603 provides a stable, high ohmic value component in compact circuits where footprint is critical.

Market Segments:

  • Aerospace
  • Military
  • Medical
  • Industrial

Features:

  • Ohmic values up to 20G
  • Tolerance down to 5%
  • Gold wire bond or solder terminations

Applications:

  • High gain amplifiers
  • Infra-red & glass break sensors
  • Smoke & gas monitors
  • Medical monitors

Benefits:

  • Single high value resistor enhances reliability and reduces field failures compared with a multi-chip solution
  • Thick-film element has higher voltage surge tolerance than thin-film, also improving reliability
LRMAP5930-Series-Welwyn

Product Specifics:

  • Resistance range 0.2mΩ to 2mΩ Request Sample
  • Excellent long term stability
  • High power rating up to 15W
  • Current sensing for power electronics
  • AEC-Q200 qualified

Product Docs

LRMAP5930 Datasheet | PDF
LRMAP5930 Release | PDF
WMHP-HS-Series-Welwyn

The WMHP-HS is a PCB mounting heatsink tailored for WMHP series power resistors. It is a compact and lightweight thermal management solution with a small PCB footprint. It can accommodate both TO-220 and TO-247 package styles, thus covering the whole range of WMHP ratings from 20 to 100W.

Product Specifics:

  • For TO-220 and TO-247 packages
  • Ideal for use with WMHP series power resistors
  • Ridged fins for higher surface area with low mass
  • Low thermal resistance
  • Black anodised finish
  • Solderable pins for robust PCB mounting

For circuit designers who need to manage temperature rise in compact power electronic assemblies we provide WMHP-HS which provides more effective cooling with lower mass than the key competing part (Ohmite)


Product Docs

WMHP-HS Datasheet | PDF
WMHP-HS Fast Facts | PDF
WMHP-HS Press Release | PDF
WMHP-HS Product Focus | PDF