Resistors MELF Resistors WRM Series AEC-Q200 High reliability Predictable pulse handling capability Tolerances down to 0.1% TCR down to 5 ppm/C All parts arAll parts are Pb-e Pb-frfree and cee and comply with EU Diromply with EU Directivective 2011/65/EU amended be 2011/65/EU amended by (EU) 2015/863 (Ry (EU) 2015/863 (RoHS3)oHS3) Electrical Data WRM 0102 WRM 0204 WRM 0207 Power rating 70C watts 0.2 0.25 0.4 Resistance Range ohms 1R0 - 1M0 R22 -5M1 R22 - 4M7 Limiting element voltage volts 200 200 250 TCR ppm/C 15, 25, 50, 100 5, 10, 15, 25, 50, 100 15, 25, 50, 100 Resistance tolerance % 0.1, 0.25, 0.5, 1, 5 Standard values E24 & E96 Thermal impedance k/W 250 200 140 Ambient temperature range C -55 to +155 -55 to +125 10 Insulation resistance ohms >10 Zero ohm jumper current rating amps 2 4 Zero ohm jumper maximum residual resistance m 15 Physical Data Dimensions (mm) & weight (g) L 1 1 L D D K L Type Weight max max max min min D D WRM 0102 2.3 1.35 1.3 0.3 1.1 0.01 1 WRM 0204 3.7 1.55 1.55 0.5 1.5 0.02 1 K L WRM 0207 6.1 2.4 2.4 0.5 2.9 0.08 Construction Terminations A metal film is deposited onto a high dissipation ceramic Material Plated steel cap. former to which tin plated teminating caps are fitted. Solderability The pure tin finish produces ageing free contacts on which low melting solders can The resistor is adjusted to value by a helical cut in the film be used. Dipped area shall be covered with and the body is protected by a lacquer coating. a smooth and bright solder coating aerft 3 seconds immersion at 215C. Marking Resistance values are colour coded with four bands, Solvent Resistance three indicating value and one indicating the multiplier. The body protection and marking are resistant to all normal (Note this describes standard marking, but certain values industrial cleaning solvents suitable for printed circuit boards. may still be supplied with the addition of a tolerance band following the multiplier.). General Note BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT Electronics own data and is considered accurate at time of going to print. www.ttelectronics.com/resistors TT Electronics plc 07.20MELF Resistors WRM Series TCR and Tolerance Range Type Reference TCR Tolerance 5% 1.0% 0.5% 0.25% 0.1% 100ppm 1R0 - 1M0 1R0 - 1M0 - - - 50ppm 1R0 - 1M0 1R0 - 1M0 8R2 - 1M0 - - WRM0102 25ppm - 49R9 - 390K 49R9 - 200K 100R - 82K 100R - 82K 15ppm - 100R - 56K 100R - 56K 100R - 56K 100R - 56K 100ppm R22 - R91 - - - - 50ppm - 1R - 5M1 10R - 1M6 22R - 332K 43R - 332K 25ppm - 4R7 - 500K 10R - 500K 22R - 402K 43R - 332K WRM0204 15ppm - - 10R - 221K 22R - 221K 43R - 221K 10ppm - - - 22R - 221K 43R - 221K 05ppm - - - 100R - 100K 100R - 100K 100ppm R22 - R91 - - - - 50ppm - 1R - 4M7 10R -1M6 - - WRM0207 25ppm - 10R - 1M 10R - 680K 51R1 - 330K 100R - 100K 15ppm - - 51R1 - 10K 51R1 - 10K 100R - 10K * TC 10ppm & 5ppm is specified over the temperature range -10C to +85C. Performance Data R/R 0204 and 0207 0102 Test 10R - <75R & 75R - 100K <10R & >332K All values >100K - 332K Short time overload* 0.05% + 0.01 0.1% + 0.01 0.25% + 0.05 0.25% + 0.05 Bending test* 0.05% + 0.01 0.1% + 0.01 0.25% + 0.05 0.25% + 0.05 Resistance to soldering heat 0.05% + 0.01 0.1% + 0.01 0.25% + 0.05 0.25% + 0.05 Temperature rapid change 0.05% + 0.01 0.1% + 0.01 0.25% + 0.05 0.25% + 0.05 Endurance* Load life 1000h 0.15% + 0.05 0.15% + 0.05 0.3% + 0.05 0.5% + 0.05 8000h 0.3% + 0.05 0.3% + 0.05 0.6% + 0.05 1.0% + 0.05 225,000h 0.9% + 0.05 0.9% + 0.05 1.8% + 0.05 3.0% + 0.05 Climatic sequence* 0.25% + 0.05 0.5% + 0.05 1.0% + 0.05 1.0% + 0.05 Damp heat steady state* 0.25% + 0.05 0.5% + 0.05 1.0% + 0.05 1.0% + 0.05 Current noise <0.05V/V <0.25V/V <3V/V <3V/V Solderability >95% coverage Voltage coefficient 0 to -0.5ppm/V Voltage proof No flashover or breakdown * Resistors to be mounted on a PC-board according to IEC 115-1, clause 4.27.1. * AEC-Q200 approval applies to all values up to and including 3M4 at TCRs above 5ppm/C and to zero ohm jumpers. General Note BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT Electronics own data and is considered accurate at time of going to print. www.ttelectronics.com/resistors TT Electronics plc 07.20