The glossary for our website

Actuators convert electrical voltage into precise mechanical movement. In piezoelectric versions, this is achieved by the inverse piezo effect in PZT ceramic. Rotima offers Piezo Haptic Actuators(30-1250 pF, designs from 2.5×0.5×0.3 mm) and Haptic Feedback Actuators with displacements of 12-120 µm at operating voltages from -15 to +200 V. Stripe Actuators from APC International complete the portfolio for dosing and valve control in medical technology, HMI and OEM systems.

AC/DC-Wandler converters(100-180 W, 700 V GaN switch, DFN8×8) and non-isolated types - HV-BUCK(650-700 V, 5-500 mA), HV-LDO (＜15mW standby), FLYBACK (6-20 W) - in SOP8/DIP8 for switching power supplies, LED drivers, industrial automation and smart home.

Spulen made of thermoplastic wire(Ø 0.015-1.0 mm), the windings of which are joined by a melted layer of baked enamel to retain their shape - by hot air, electric shock, oven or hydrogen flame. Rotima manufactures these according to customer specifications: single and bifilar windings, HF strands, assembled in shell cores. Mini baked enamel coils from 0.70 mm inner diameter are produced fully automatically .

An Bipolartransistor mit isolierter Gate-Elektrodecombines the voltage-controlled control of a MOSFET with the current-carrying capacity of a bipolar transistor. Rotima offers the BID series from Bourns with trench-gatefield-stop technology: VCE up to 650 V, IC up to 75 A @ 100 °C, VCE(sat) from 1.35 V in TO-247 and TO-252, for SMPS, UPS and PFC circuits, operating temperature -55 °C to +175 °C.

Chip-Widerstände are lead-free SMD components on a ceramic carrier with a thick-film resistor layer. Rotima offers thick-film types from Hongda Capacitors in sizes 01005 to 2512 (1/32 W to 1 W), resistance ranges 0.1 Ω-100 MΩ, tolerances ±0.5-5 %, TCR ±100-500 ppm/°C. Arrays and networks according to AEC-Q200 for automotive, medical technology and industrial electronics.

Chemical hoses are designed for the safe transportation of aggressive media - acids, alkalis, solvents. Designed to withstand chemical, thermal and mechanical stress. Rotima offers variants made of PTFE, FKM fluoroelastomer, silicone, PVC and PE: pressure-resistant due to fabric reinforcement or wire braiding, temperature-stable and vacuum-resistant. Available as standard and customized high-pressure versions for chemical, laboratory and industrial systems.

Coil inductors are wound inductors for signal stabilization, EMC filtering and energy storage in DC-DC converters and RF circuits. Rotima offers series of Hongda Capacitors: Whole-Shield types(HDCDH, HDSFD, HDSL) with inductances from 1-1000 µH, DCR from 4.7 mΩ, Isat up to 28 A as well as unshielded CD types(HDSD) for compact layouts. Test frequencies 1-100 kHz, RoHS-compliant.

Wirewound resistors consist of a resistor alloy wound around a ceramic or axial core. Rotima offers series of VPG Foil Resistors and Bourns: Wirewound types with TCR from ±0.2 ppm/°C, tolerances from ±0.005 %, rated power 0.1-2500 W - as fusible, through-hole and ceramic packages. Used in measurement technology, medical devices, telecommunications and high-performance electronics.

Pressure sensors convert mechanical pressure into an electrical signal via a piezoresistive silicon diaphragm(MEMS technology). Rotima offers the BPS series from Bourns: compensated versions(BPS110-BPS170) with 12-13 bit DAC, accuracy ±0.25 %FS, measuring ranges 0.15-500 psi, operation -40 °C to +150 °C. As analog and I²C output. Uncompensated BPS300 types for customer-specific calibration, SMD design.

Diodes are p-n junction semiconductor devices that conduct current in the forward direction and block current in the reverse direction. Rotima offers chip diodes from Bourns(AEC-Q100, JEDEC-compliant, RoHS): small signal diodes in 0603/1005 with Cu/Ni/Au connections, Schottky, Zener and high-speed switching diodes in SOT23 to SMC packages as well as Power TVS diodes with surge current capability up to 15 kA for overvoltage protection.

Chokes are inductive components - a wire coil around a magnetic core - that limit current flow, attenuate voltage peaks and filter HF interference. Core parameters are inductance L [H], saturation current I_sat, rated current I_rated, DC resistance R_DC and quality factor Q. Rotima manufactures toroidal chokes ( EMC filtering) and storage chokes ( DC-DC converters, switching power supplies) according to customer specifications in cooperation with Kaschke Components.

Electrical insulating tapes insulate electrical conductors, tape coils and shield against EMC. Rotima stocks the 3M range: PTFE film up to 15 kV / 180 °C, polyimide film (0.025 mm) up to 7.5 kV / 180 °C, PVC film up to 12 kV, glass fabric tape up to 3 kV / 200 °C. Plus EMC shielding foils made of copper and aluminum as well as electrically conductive fabric tapes - UL, CSA and IEC certified.

EMC shielding foils made of aluminum dissipate electrostatic charges, ground assemblies and shield against electromagnetic interference fields. Rotima offers three 3M types: Foil 1170 (0.081 mm, conductive acrylic adhesive, 10 MΩ), embossed foil 1267 (0.127 mm, non-conductive, 5 MΩ) and polyester-coated AL-36FR (0.061 mm, solvent-resistant, 20 MΩ) - all easily die-cut for automated manufacturing.

EI transformers are based on a core made up of E- and I-shaped laminations - cost-effective, proven for 50/60 Hz applications. Rotima manufactures PE, PEV (encapsulated), PES (with shield) and WEK series in core sizes 30-150 mm according to customer specifications: defined transformation ratios, insulation material classes B to H, for switching power supplies, control systems and medical technology in accordance with IEC 60076.

Electronic components are passive and active components for controlling, converting and filtering electrical signals and energy. Rotima stocks resistors (chip, wire, shunt), capacitors (MLCC, electrolytic, tantalum), inductors, GaN ICs, IGBT, diodes(AEC-Q100), sensors, actuators and circuit protection - from Bourns, VPG Foil Resistors, Hongda Capacitors and Dongke Semiconductor.

Earthing straps are fine-stranded copper or aluminum braids for equipotential bonding, protective conductor connection and EMC earthing. Rotima offers Cu-ETP types(99.9 % Cu, max. 1.7241 µΩ-cm at 20 °C) as flat, round, extra-flex and PBFC braids as well as aluminum braids (EN 1715-2, 61.5 % IACS, -50 °C to +100 °C) - bare or tinned, in cross-sections 6-120 mm², UL-certified according to UL 467.

Encoders are digital rotary encoders that convert rotary motion into TTL/CMOS pulses via contacting, magnetic or optical sensing. Rotima offers Bourns series: Contacting(PEC/ECW, 9-22 mm, 6-36 PPR, IP40/IP67), Optical(EM14/EN/ES14, 8-256 PPR, up to 3000 rpm), Magnetic(EMS22, 32-1024 PPR, up to 10,000 rpm, IP65, 50-100 million revolutions) for HMI, motor control and industrial automation.

Fine wires are individually enameled copper wires with diameters less than twice the skin depth of the operating frequency. This design drastically reduces eddy current losses and proximity effect from 20 kHz. At 100 kHz, the optimum wire thickness is less than 0.10 mm. 50-500 individual wires reduce the AC resistance by a factor of 5-10 compared to solid wires. Rotima supplies PACK Litz wire fine wires in accordance with DIN EN 9001 for switching power supplies, resonant converters and inductive charging coils.

Ferrite cores are sintered ceramic components made of iron oxide and metal oxides with high permeability and low electrical conductivity and therefore low eddy currents up to the MHz range. MnZn ferrites ( µr 2000-15,000, up to 1 MHz) are suitable for switching power supplies and chokes; NiZn ferrites (µr 10-1500, up to 100 MHz) for EMC filters and HF. Rotima stocks cores from Kaschke Components, Proterial Europe and Samwha Electronics in EE, RM, PQ, toroidal and planar designs.

Film capacitors consist of two metal layers with plastic film as dielectric. Polypropylene(MKP) up to 1000 V AC with low tan δ and self-healing effect, polyester(MKT) up to 630 V AC. Typical service life 100,000-200,000 h; according to the 10°C rule, it is halved for every 10 K increase in temperature. Rotima stocks high-pulse, interference suppression and spark-killer capacitors from AIC Europe and Okaya for power electronics, EMC and motor controls.

Humidity sensors measure relative humidity capacitively. A moisture-sensitive polymer changes its dielectric constant in proportion to the water vapor concentration, which can be measured as a change in capacitance. Rotima offers Bourns® capacitive humidity sensors with high measurement accuracy, long-term stability and miniature design for control cabinet monitoring, climate control, server rooms, medical technology and automotive electronics.

Direct voltage converters (DC-DC converters) convert one direct voltage into another. Using PWM-controlled MOSFET switching with energy storage in inductive components.Step-up convertersincrease and step-down converters reduce the voltage; efficiencies of over 95 % can be achieved. Rotima offers DC converters from Bourns for industrial controls, medical technology, automotive and mobile electronics, as standard and customized versions.

Glass fabric tape is a tear-resistant, elastic insulating tape on a glass fabric carrier -resistant up to 200 °C and 3.0 kV breakdown voltage, tensile strength up to 314 N/10 mm. Rotima offers three 3M types: 27 (abrasion-resistant, printable), 69 (flame-retardant adhesive for high-temperature use) and 79 (solvent-resistant) - UL, CSA and OANZ2-certified for cable fastening, coil taping and transformer insulation.

Braided sleevings are braided protective sleevings made of PET and polyolefin to protect cables and wires from mechanical abrasion, heat and electromagnetic interference. Rotimas types operate continuously from -40 °C to +125 °C, shrink 2:1 from approx. 120 °C and are self-extinguishing within 60 s for industrial cable assemblies, electrical cables and control cabinet installations.

Fabric shrink sleeves combine a polyolefin inner jacket with woven-in PET synthetic fibers. The hybrid structure provides electrical insulation and extreme abrasion protection against vibration and friction. Material PET & polyolefin, shrink ratio 2:1 from approx. 120 °C, continuous operation -40 °C to +125 °C, self-extinguishing within 60 s. Rotima supplies these for cable assembly, vehicle technology and NVH-relevant cable protection applications.

High-pulse capacitors are film capacitors that release stored energy in short, powerful pulses. With low ESR, low ESL and self-healing effect in the event of micro-damage. Rotima carries Okaya series: HCP-S(450-1250 V, 0.01-68 µF), C1NP(250-1250 V), snubber types CF99/CF78 (630 V) and AFV/AFC/AFP(450-630 V) for laser technology, lithotripters, pulse generators and welding systems.

Hybrid-Tantalkondensatoren combine a tantalum anode with a Ta₂O₅ dielectric with a conductive polymer or liquid electrolyte. This results in lower ESR than classic tantalum types, higher current carrying capacity and longer service life. Rotima offers Hongda HTHC series(10-125 V, 160 µF-230,000 µF, ESR 0.03-0.6 Ω at 1 kHz, ISO9001/IATF16949) for ADAS, battery management systems, DC/DC converters and medical technology.

Adjustment potentiometers , also known as trimmers or Trimpot®, are adjustable miniature resistors with a cermet or wire-wound resistor element that are operated with a screwdriver for one-off or occasional circuit adjustment. Single-turn types with direct drive are suitable for quick coarse adjustments, multi-turn types (up to 25 turns) for higher resolution. Rotima carries Bourns® Trimpot®, 10 Ω-2 MΩ, THT and SMD for precision calibration in measurement, medical and industrial electronics.

Capacitors store electrical energy in an electrical field between two electrodes and are used for voltage smoothing, filtering and energy storage. Rotima offers four types: Electrolytic capacitors ( screw terminal, snap-in, SMT, radial, polymer), film capacitors MKP/MKT from AIC Europe and Okaya, ceramic capacitors MLCC (NP0, X7R, X5R, Y5V) and tantalum capacitors including hybrid HTHC series - all from Hongda Capacitors, ISO9001/IATF16949.

Ceramic capacitors (MLCC) consist of stacked ceramic dielectric layers with staggered electrodes. Class 1 types(NP0/C0G, ±30 ppm/°C) for precision circuits, Class 2 types(X7R ±15%, X5R, Y5V) for high capacitance density. Rotima offers Hongda series HLC (0.1 pF-220 µF, 4-100 V, sizes 0402-2225, -55 to +125 °C) and MQ(high voltage up to 7200 V, ISO9001/IATF16949) - for RF decoupling, EMC filtering and power electronics.

Small transformers convert alternating voltages by electromagnetic induction. The turns ratio determines the transmission ratio. Rotima manufactures three customized core shapes: EI (laminations PE/PES/WEK 30-150 mm, compact PCB transformers), UI (PU/PUS/PUV 30-60 mm, efficient coupling) and M (PM/PMD/PMV/SMD 42-102 mm, low stray field) for power supplies, galvanic isolation, impedance matching and signal transmission at 50/60 Hz.

Cold-shrink sleeves made of ethylene-propylene-diene rubber are pre-stressed elastomer sleeves that fit automatically without a heat source after the support spiral is removed. Temperature range -40 °C to +90 °C, shrink ratio 2:1, insulation up to 1 kV, resistant to UV, ozone and moisture. Rotima supplies 3M types for energy technology and telecommunications for cable sleeves, connectors and outdoor installations where heat application is excluded.

Power resistors convert electrical energy into heat. In wire, thick film or precision foil technology and limit currents under high thermal load. Rotima offers VPG foil series: Wirewound (BR/BRT 60-500 W, Metal Clad; PWR-SMD 0.5-10 W; UAL up to 250 kΩ / 50 W), Power (FHR up to 2500 W, ±50 ppm; VHP4Z TCR ±0.2 ppm/°C) from Bourns and VPG for motor controls, power supplies and BMS.

Light sensors detect light without contact using an infrared LED as a transmitter and a photodiode as a receiver. Transmissive photointerrupters (RPU) detect beam interruptions - for paper flow and banknote detection; photo-reflectors detect reflected light for barcodes and edge detection; infrared LEDs (RLD) serve as an encoder light source. Rotima offers all three series from Okaya Electric Industries for industrial automation and printing technology.

Air coils are coreless inductors made of wound enameled copper wire without a ferromagnetic core. This means no saturation effect, low losses and a high self-resonant frequency(SRF). Rotima manufactures enameled coils made of thermoplastic wire (Ø 0.015-1.0 mm), single and bifilar, with HF strands, assembled in shell cores; mini enameled coils from 0.70 mm inner diameter, fully automatic for HF circuits, resonant circuits, RFID and induction applications.

Litz wires are bundles of many individually enameled copper wires that drastically reduce the skin and proximity effect at high frequencies. Rotima supplies two types of PACK Litz Wire (DIN EN 9001, DIN/VDE/IEC/UL): RUPALIT® high-frequency l itz wires - single wire Ø below the skin depth of the operating frequency(at 1 MHz: δ ≈ 0.066 mm), e.g. 500 × 0.05 mm - and fine wires from Ø 0.015 mm for switching power supplies, resonant converters and inductive charging coils.

Food hoses are designed for the safe transport of food and beverages - made of food-safe, odorless and tasteless materials without harmful migration. Rotima offers five types: Silicone tubing(FDA-certified, BPA-free, for dairy and beverage processing), fluoroplastic tubing, protective tubing, heat-shrink tubing and specialty tubing - all compliant with FDA 21 CFR and EU Regulation 10/2011, CIP-cleanable.

Metal meshes are braided structures made of metal threads, as flat braid (2-500 mm², Ø 0.10-0.20 mm) or round braid (2-300 mm², Ø 0.10-0.25 mm) for earthing, EMC shielding and power connections. Rotima offers Cu-ETP types according to NF EN 13602 (99.9 % Cu, max. 1.7241 µΩ-cm at 20 °C, min. 200 MPa) as well as stainless steel and aluminum variants. Bare, tin-plated, silver-plated or nickel-plated. For electrical engineering, aviation and clean room technology.

M-transformers are based on a core of M-shaped laminations that reduce magnetic leakage fluxes and reduce heat generation - making them particularly low leakage field and efficient. Rotima manufactures the PM and PMD (42 mm), PMS and PMDS (55-102 mm), PMV(42-74 mm) as well as SM and SMD (55-102 mm, extra low leakage) series for power supplies, galvanic isolation and impedance matching at 50/60 Hz.

Variators consist of many stacked MOV layers made of zinc oxide ceramic - when the response voltage is exceeded, the resistance drops abruptly and dissipates transients. Compact design( 2220package ) with Imax 2 kA allows it to outperform larger single layer MOVs (4032, Imax 1200 A); operating voltages typically below 200 V at 1 mA. Rotima carries MLVs from Bourns® for mobile devices, miniature applications and sensitive low-voltage electronics.

Mains interference suppression filters suppress conducted EMI interference in the power grid through impedance matching: passive LC networks consisting of capacitors(Y/Pi filters), inductors and ferrite cores offer high impedance for RF interference and low impedance for the mains voltage. They filter switching interference from power supply units and switching regulators and ensure EMC conformity. Rotima offers standard and customized Bourns® line noise filters for industrial automation, medical technology and telecommunications.

Nicht-isolierte AC-DC Wandler convert AC mains voltage directly into DC voltage without galvanic isolation. Via rectifier, filter and switching regulator. Rotima carries Dongke series: HV-BUCK (DK503/5320/5360/5511/5512/5522-5524, 650-700 V, RDS(ON) 3.6-18 Ω, 5-500 mA), HV-LDO (DK5030-5032, standby), BUCK/BUCKBOOST/FLYBACK (DK5502/5503, 6-12 W) and Non-isolated Flyback (DK5710, 20 W) - in SOP8/DIP8/DIP7 for LED drivers, industrial automation and smart home.

Electronic component protectors from the LSP series prevent the total failure of an LED string in the event of a defective individual diode: if an LED opens the circuit, the LSP automatically routes the current around the failed LED - the remaining LEDs remain active. The cost-effective alternative to conventional solutions minimizes maintenance costs. Rotima stocks Bourns® LSP for street lighting, general lighting fixtures and backlit signage systems.

On-board resistors generate a measurable voltage drop proportional to the flowing current (U=R-I) and are integrated directly on the circuit board. Rotima stocks SBA-SBJ series from Shivalik Bimetal Controls: resistors 0-50 mΩ, sizes 1206-5930, power ratings up to 15 W, tolerances ±1-5 %; joined by electron beam welding and diffusion bonding of manganese/copper - for BMS, automotive and energy measuring devices.

Off-board are current measuring resistors mounted externally to the main circuit for high-current applications. With superior heat dissipation due to large-format design and heat sink connection. Rotima carries SBY/SBL/SBZ series from Shivalik Bimetal Controls: resistors 0.025-1 mΩ, frame sizes 3515-8518, power ratings 3-36 W, tolerance ±5-10 %; electron beam welded from manganese/copper for EV battery systems, industrial controls and smart grid applications.

Polyimide tubing (PI) is high-performance thermoset tubing, PFAS-free, manufactured using the dip-coat process with a continuous service temperature of up to +220 °C (short-term up to +400 °C), dielectric strength 22 kV/mm, internal diameters from 0.051 mm (AWG 44) and wall thicknesses from 0.0064 mm. Rotima offers Electrical Grade (micro cables, coils, relays) and Medical Grade (＜100 ppm Cu, for catheters and endoscopy) resistant to UV, ionizing radiation and most chemicals.

Piezoelemente made of PZT ceramic (relative permittivity 1700-3800) convert mechanical force into electrical voltage and vice versa, via direct and inverse piezoelectricity. Rotima carries standard and customized types from APC International (Cylinders, Stripe Actuators, Stack Actuators, Disc Benders, Ultrasonic Transducers, Buzzers, Nebulizers) and Audiowell (Ultrasonic, Flow, Level, DEF Sensors) for medical, industrial automation and automotive applications.

Potentiometers are adjustable resistors with a mechanical wiper on a resistor element made of carbon, cermet or conductive plastic. The wiper divides the input voltage variably(voltage divider). Rotima carries Bourns® series: Commercial Slide (manual/motorized), Precision Controls (22-51 mm, single/multiturn, up to IP 68), Linear Motion Potentiometers and Trimpot® (10 Ω-2 MΩ, single/multiturn) for audio, instrumentation and industrial controls.

The cross-section of an electrical conductor, specified in mm², determines its current-carrying capacity and electrical resistance: the larger the cross-section, the lower the voltage drop per meter. Rotima supplies flat and round copper ETP braids (99.9 % Cu, max. 1.7241 µΩ-cm at 20 °C) in cross-sections of 2-500 mm² as well as aluminum braids(61.5 % IACS) for earthing, equipotential bonding and EMC shielding in electrical engineering and industrial systems.

Toroidal chokes on toroidal ferrite or iron powder core. The closed magnetic circuit minimizes stray fields and magnetic radiation. Rotima offers three series from Kaschke Components: current-compensated toroidal chokes (common mode filtering, EN 138100 / DIN EN60938-2), PFC chokes and PFC circuits.

Radial electrolytic capacitors consist of an aluminum anode with Al₂O₃ dielectric and a liquid electrolyte. Both connections come out on one side and allow vertical PCB mounting. Rotima carries Hongda series (ISO9001/IATF16949): General Purpose RGR/RRL(6.3-450 V, 0.1-33,000 µF, up to 2,000 h), Long Life RLZ (up to 12,000 h, -40 to +105 °C), High Temperature RLL (up to +130 °C, 5,000-6,000 h), Low Impedance RRC(4,000-10,000 h) and Super Low Temp RGK(-55 to +105 °C) - for switching power supplies, LED drivers and solar inverters.

Radial tantalum capacitors consist of a sintered tantalum anode with Ta₂O₅ dielectric and a MnO₂ or polymer cathode - no liquid electrolyte, therefore no drying out and low leakage currents. Rotima carries the Hongda type CA42(ISO9001/IATF16949): Capacitance 0.68->680 µF, dissipation factor DF 4-16 % at 25 °C, leakage current DCL 8I/10I at 85/125 °C, operation -55 to +125 °C for telecommunications, automotive electronics and medical technology.

Heat-shrinkable tubing is heat-shrinkable polyolefin, fluoropolymer or elastomer tubing that shrinks to a ratio of 2:1 or 3:1 when heat is applied and electrically insulates, mechanically protects and seals cables. Rotima carries: Polyolefin thin-walled/medium-walled/thick-walled (with/without internal adhesive, halogen-free, yellow/green), fluoropolymer RT-375 (crystal clear), PVDF Kynar, fluoroelastomer VITON-E, rigid PVC Kopalon (super-thin, for battery packs), end caps and molded parts can be cut to special dimensions.

Storage chokes are inductors with a defined air gap in the ferrite or iron powder core. The air gap reduces the effective permeability, prevents magnetic saturation at high DC current and linearizes the energy storage. Characteristic values are inductance L [µH], saturation current I_sat, DC resistance R_DC and AL value [nH/N²]. Rotima manufactures storage chokes according to customer specifications in cooperation with Kaschke Components for DC/DC converters, switching power supplies and PFC circuits.

Quick connectors enable a tool-free, reverse polarity protected power and data connection using hermaphroditic plugs. Each element serves as both plug and socket. Rotima carries Anderson Power Products (APP®, founded in 1877): Powerpole PP15-PP180 (low voltage), Multipole SB 50-SB 350(up to 350 A), SBE/SBX series as well as Compact PowerMod - REACH/RoHS compliant for electromobility, lithium-ion systems, telecommunications and photovoltaics.

Current sensors measure the electrical current in real time. With shunt-based technology via the voltage drop across a low-ohm measuring resistor (U = R - I), with Hall-effect sensors contactless via the magnetic field of the conductor. Rotima offers Bourns® current sensors in analog and digital versions, temperature compensated - for battery management, EV charging stations, switching power supplies and industrial energy monitoring.

Temperature switches open or close an electrical circuit when a defined switching temperature is reached. In the case of bimetal types, this is due to the different coefficients of thermal expansion of two connected metal strips, which deform when the temperature changes and actuate the contact. Rotima offers Uchiya temperature switches for overheating protection of electronic components for small motors, transformers, switching power supplies, electronic circuit boards and industrial machines, as standard and customized versions.

Thermistor heaters are self-regulating heating elements made of doped BaTiO₃ ceramic with a positive temperature coefficient (PTC). As the temperature rises, their resistance increases sharply, which limits the current and stabilizes a defined equilibrium temperature without an external thermostat circuit. Rotima carries Ceramic PTC Heaters from Bourns® (AEC-Q200 compliant) - for automotive electronics, HMI, medical and industrial controls that require a compact, self-regulating heating solution.

Trimmers are adjustable miniature resistors with cermet (glass-to-metal thick film) or wirewound resistive element and mechanical wiper that are used with a screwdriver for circuit adjustment. Rotima offers Bourns® Trimpot®: single-turn (direct drive, sealed and open-frame) and multiturn(up to 25 turns, higher resolution), 10 Ω-2 MΩ, THT and SMD - for precision calibration, circuit drift correction and fine tuning in measurement, medical and industrial electronics.

Transformers convert alternating voltages by electromagnetic induction. The number of turns between the primary and secondary windings determines the ratio. Transformers transmit signals electrically isolated. Rotima carries Bourns® types: Power transformers (power electronics, voltage matching), planar transformers(compact SMD design), AEC-Q200 compliant transformers (automotive, BMS) and chip LAN transformers (network technology) for industrial, automotive and communication applications.

Tantalum capacitors consist of a sintered tantalum anode with Ta₂O₅ dielectric and a conductive cathode. No liquid electrolyte, therefore high capacitance density, low leakage currents and temperature stability -55 to +125 °C. Rotima carries Hongda series(ISO9001/IATF16949): Radial CA42 (THT, 0.68->680 µF), SMT CA45/CA55 (0.68-2,200 µF, 2.5-100 V), Automotive QCA45 and Hybrid HTHC (ESR 0.03-0.6 Ω, up to 230,000 µF) for telecommunications, automotive and medical technology.

Transistors are active semiconductor components for switching and amplifying electrical currents. BJTs are controlled by base current, FETs by gate voltage and IGBTs by a combination of both principles. Rotima only supplies the IGBT as a transistor type: BID series from Bourns (Trench-Gate Field-Stop), VCE 650 V, IC 75 A @ 100 °C, operating temperature -55 °C to +175 °C - in TO-247/TO-252 for SMPS, UPS and PFC.

Ultrasonic sensors detect distances, fill levels and flow rates without contact: A piezoelectric transducer emits high-frequency sound pulses; the transit time of the reflected echo provides the measured variable, regardless of light conditions and surface properties. Rotima offers Audiowell sensors with application-specific frequencies, measuring ranges and housing designs for industrial tanks, AdBlue systems, flow measurement in gases and liquids as well as high-temperature and underwater variants.

Ultrasonic level sensors measure the level of liquids or bulk solids without contact by ultrasonic transit time without moving parts, therefore higher accuracy and reliability than reed float sensors. Audiowell UM0059 measures DEF/AdBlue in SCR systems: Measuring range 150 mm, resolution 4 mm, accuracy ±5 mm, analog output 0-5 V, operation -40 to +85 °C, DC 12 V / max. 25 mA. Rotima distributes Audiowell Level Sensors for automotive, industrial and tank applications.

Ultrasonic rangefinders measure distances contactlessly via the transit time of ultrasonic pulses. The sensor transmits a pulse, receives the echo and outputs the distance as a pulse width or UART signal. Audiowell UM0034: 60 kHz, measuring range 20-1000 mm, accuracy 1 cm, DC 5 V / ≤9 mA, UART (TTL), 0-65 °C, IP-protected; UM0090 up to 3 m. Rotima distributes Audiowell rangefinders for AGVs, robotics, parking aids and autonomous vehicle systems.

Transformers transmit AC voltage signals electrically isolated by electromagnetic induction without a conductive connection between the primary and secondary circuits, eliminating potential differences and suppressing signal interference. Rotima carries Bourns® types: AEC-Q200 compliant transformers for BMS and automotive electronics, chip LAN transformers for interference-free network connections in routers and switches as well as planar transformers in compact SMD design for automotive, telecommunication and industrial applications.

Surge protection devices discharge transient overvoltages caused by lightning strikes, switching operations or induction before they damage sensitive electronics. Varistors (MOV) limit the voltage bidirectionally , gas discharge tubes (GDT) absorb surge currents above 25 kA, TVS diodes react in nanoseconds, TISP®thyristors(15-520 V) protect telecommunication lines. Rotima offers Okaya and Bourns solutions for industry, telecommunications and IT infrastructure.

Overcurrent protection interrupts or limits the flow of current when a fault current exceeds the rated capacity of components by irreversible melting (fusing) or reversible tripping. Rotima carries Bourns® types: Multifuse® PPTC(resettable, exponential resistance rise), Ceramic PTC (telecom, AC protection), SinglFuse™ SMD(0402-3812, one-time), Mini Breaker (TCO, thermal) and TBU® High-Speed Protectors (MOSFET-based) for battery packs, charging electronics, telecom and industrial controls.

Varistors are non-linear, bidirectional overvoltage protection components made of zinc oxide ceramic. Below the response voltage, the resistance drops abruptly and transients are dissipated. Rotima offers two types of Bourns®: Metal Oxide Varistors(MOV, various form factors, high impulse energy) for industrial, IT and household appliances and Multilayer Varistors(MLV, 0201-2220 package, Imax up to 2 kA) for miniature applications and low voltage electronics.

Potting compounds are curing synthetic resins, epoxy (cold or hot curing) or polyurethane, which completely enclose electronic components and thus protect them from moisture, dust, vibration and foreign bodies as well as insulating them electrically and fixing them mechanically. Rotima stocks 3M Scotchcast grades(8, 9, 226, 235, 280, 281) in high to low viscosity versions, Shore hardness 75 Shore A to 70 Shore D, insulation classes B/F for transformers, coils, capacitors and entire assemblies.

Resistors are passive components that limit the flow of current according to Ohm's law (U = R - I), divide voltages and attenuate signals. Characterized by resistance value [Ω], tolerance, power rating [W] and temperature coefficient TCR [ppm/°C]. Rotima supplies chip resistors (Hongda, thick film, 01005-2512), wirewound and power resistors (VPG, Bourns, TCR from ±0.2 ppm/°C), current measuring resistors/shunts(Shivalik, on/off board) and trimmers (Bourns® Trimpot®) for measurement technology, automotive and industrial electronics.

Converters convert electrical quantities. Voltage, current or signal form from one level or type to another. DC-DC converters(step-up/step-down, PWM-controlled) achieve efficiencies above 95 %, AC-DC converters rectify and regulate mains voltage. Rotima offers DC-DC converters, voltage converters and current converters from Bourns® as well as GaN-based AC-DC converter ICs from Dongke Semiconductor for industrial control, automotive and medical applications.

X capacitors are safety-certified interference suppression capacitors that are connected between the phase and neutral conductor. They short-circuit high-frequency push-pull interference from 150 kHz and allow useful signals at 50/60 Hz to pass through unhindered. Typical capacitance values are between 100 nF and 1 µF; there must be no risk of fire in the event of a dielectric breakdown(class X1/X2 according to IEC 60384-14). Rotima supplies interference suppression capacitors from Okaya Electric Industries for switching power supplies, frequency converters and industrial control systems.

The X7R capacitor is a Class 2 MLCC dielectric class with a capacitance change of ±15 % over the temperature range -55 to +125 °C, a compromise between stability and high capacitance density. Compared to NP0/C0G, X7R offers higher capacitance values in a compact design, but shows voltage dependence (DC bias effect). Rotima offers Hongda MLCCs HLC series X7R (100 pF-47 µF, 4-100 V, sizes 0402-2225, ISO9001/IATF16949) for decoupling, EMC filtering and power electronics.

Y capacitors are safety-certified interference suppression capacitors that are connected between the mains conductor and protective earth. They dissipate high-frequency common-mode interference without generating a dangerous touch current in the event of a dielectric breakdown. Class Y1 (up to 8 kV impulse voltage) and Y2 (up to 5 kV) are approved in accordance with IEC 60384-14. Rotima supplies interference suppression and film capacitors from AIC Europe and Okaya for EMC-compliant power supply units and industrial control systems.

A Zener diode uses controlled Zener breakdown in the reverse direction. When the Zener voltage UZ is reached, the voltage remains almost constant, independent of the current and thus serves as a voltage reference or overvoltage protection. Rotima offers Zener types from the Bourns® diode range(AEC-Q100, JEDEC-compliant, RoHS) in SMD designs SOT23 to SMC for voltage regulation, reference voltages and protection circuits in automotive, medical and industrial electronics.

A zinc oxide varistor (MOV - Metal Oxide Varistor) is a non-linear, bidirectional protective element made of sintered ZnO ceramic with doping additives. Below the response voltage, it behaves with high impedance; if this is exceeded, the resistance collapses abruptly and the transient energy is dissipated. In contrast to the diode, the MOV has the same effect in both current directions. Rotima offers Metal Oxide Varistors from Bourns® in various form factors for industrial, telecommunications and household appliances.