KTR18 Resistors Endured high voltage fixed thick film chip resistors KTR18 (3216 size: 1 / 4W) z Features 1) Power rating of 1 / 4W 2) Limiting element voltage of KTR series is twice compared with that of MCR series. 3) Highly reliable chip resistor Ruthenium oxide dielectric offers superior resistance to the elements. 4) ROHM resistors have approved ISO9001 certification. Design and specifications are subject to change without notice. Carefully check the specification sheet before using or ordering it. z Ratings Item Conditions Specifications 0.25W (1 / 4W) Rated power Power must be derated according to the power derating curve in at 70C Figure 1 when ambient temperature exceeds 70C. 100 80 60 40 20 0 55 0 70 100 155 AMBIENT TEMPERATURE (C) Fig.1 Rated voltage The voltage rating is calculated by the following equation. If the value obtained exceeds the limiting element voltage, the voltage rating is equal to the maximum operating voltage. E: Rated voltage (V) E= PR P: Rated power (W) Limiting element voltage 400V R: Nominal resistance ( ) Nominal resistance See Table 1. 55C to +155C Operating temperature 1/6 POWER LOAD (%)KTR18 Resistors Table 1 Resistance range Resistance temperature coefficient Resistance tolerance ( ) (ppm / C) F (1%) 5.6 R 10M (E24,96) 100 J (5%) 5.6 R 10M (E24) 200 z Before using components in circuits where they will be exposed to transients such as pulse loads (shortduration, highlevel loads), be certain to evaluate the component in the mounted state. In addition, the reliability and performance of this component cannot be guaranteed if it is used with a steady state voltage that is greater than its rated voltage. z Characteristics Guaranteed value Item Test conditions (JIS C 5201-1) Resistor type J : 5% Resistance JIS C 5201-1 4.5 F : 1% Variation of resistance JIS C 5201-1 4.8 See Table.1 with temperature Measurement : 55 / +25 / +125C JIS C 5201-1 4.13 Rated voltage (current) 2.5, 2s. Overload (2.0%+0.1 ) Limiting Element Voltage2 : 800V JIS C 5201-1 4.17 A new uniform coating of minimum of RosinEthanol (25%WT) Solderability 95% of the surface being immersed Soldering condition : 2355C and no soldering damage. Duration of immersion : 2.00.5s. JIS C 5201-1 4.18 Resistance to (1.0%+0.05 ) Soldering condition : 2605C soldering heat No remarkable abnormality on the appearance. Duration of immersion : 101s. Rapid change of JIS C 5201-1 4.19 (1.0%+0.05 ) Test temp. : 55C to +125C 5cyc temperature JIS C 5201-1 4.24 Damp heat, steady state (3.0%+0.1 ) 40C, 93%RH Test time : 1,000h to 1,048h JIS C 5201-1 4.25.1 Rated voltage (current), 70C Endurance at 70C (3.0%+0.1 ) 1.5h : ON 0.5h : OFF Test time : 1,000h to 1,048h JIS C 5201-1 4.25.3 Endurance (3.0%+0.1 ) 155C Test time : 1,000h to 1,048h JIS C 5201-1 4.29 Resistance to solvent (1.0%+0.05 ) 235C, Immersion cleaning, 50.5min. Solvent : 2-propanol Bend strength of (1.0%+0.05 ) JIS C 5201-1 4.33 the end face plating Without mechanical damage such as breaks. 2/6