TFSC680RJE

TFS Series Surge Capable Thick Film Non Inductive F e at u r e s • Appropriate for medical surge protection applications • Ideal to replace standard carbon composition resistors • Custom dimensions, values, tolerances and characteristics available The TFS Series has been specifically developed to absorb large amounts of energy by efficient use of its compact mass. Ideal for medical surge protection applications, these thick film resistors offer non-inductive performance in an axial package. Uses include power supply conversion, electron microscopes, X-ray systems, high-resolution CRT displays, and geophysical instrument related products. S e r i e s S p e c i f i c at i o n s Type TFSA TFSB TFSC TFSD TFSE TFSF U (KV) 3 3.5 4 7 7 11 Energy* (J) 6 9 11 33 44 55 Power (W) 0.5 0.5 0.75 1 1.5 2 *Published energy rating is for 10ms pulse. For shorter pulses energy rating has to be derated according to Max. Individual Pulse Rating chart and Single Pulse Energy Rating considerations. characteristics Notes Resistive Element Thick Film Encapsulation Screen Printed Glass • Momentary overload capability is 5 times rated power for 1 second or 2 times rated power for 5 seconds. Always verify designs with pulse and surge conditions through thorough testing of the design at maximum operating temperature and maximum pulse loading (or some margin above maximum pulse loading). Resistance Value 100Ω up to 100KΩ Temperature Coefficient 100ppm/°C Tolerance 1%, 2%, 5%, 10% • Damage to the resistor by excessive pulse loading is generally indicated by an increasing resistance of the resistor. Operating Temperature -55°C to +200°C Test VDE 0750 (Pulse Duration 10 msec) • Energy ratings are based on single pulses (at least 1 minute between pulses). • For multiple pulse applications the energy pulse rating should be reduced and the average power should not exceed the nominal power rating of the selected model. • See Single Pulse Energy section for more information dimensions mm C A Type B 0.50mm 0.25mm H E TFSA TFSB Watts A B C H E 0.5 9 5.5 10 0.7 1.3 ~ 1.6 0.5 TFSC 0.75 TFSE 1.5 TFSD TFSF 1 2 11 5.5 13 5.5 21 10.5 21 26 8 10.5 10 10 10 10 10 0.7 0.7 0.9 0.9 0.9 1.3 ~ 1.6 1.3 ~ 1.6 1.4 ~ 1.8 1.4 ~ 1.8 1.4 ~ 1.8 (continued) 58 1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com TFS Series Surge Capable Thick Film Non Inductive S i n g l e P u l s e E n e r g y R at i n g Example A 1µF capacitor is charged to 3.5kV and model TFSC, 1KOhm has been selected. Model TFSC is rated for 4kV, so the peak voltage of 3.5kV is acceptable. 1 Ea = –– CV2 = 6.1J 2 ta = R C = 1 ms 6.1J Er = ––– x 100 = 55% 11J According to the pulse chart, an energy ratio of 55% for a pulse width of 1ms falls well above the energy curve. The limit is actually located around 25-30%. Model TFSC cannot be used for this application. A bigger model should be chosen, for example TFSD. Model TFSD, 1KOhm, can be used for this application because we have an energy ratio Er of 18%, which is below the energy curve. 6.1J Er = ––– x 100 = 18% 33J Maximum Individual Pulse Rating 1000 Energy Rating % Although Ohmite’s TFS Series resistors have been specially designed and developed to absorb much more energy than standard resistors, pulses and transients require special consideration since they cause an instantaneous temperature rise in the resistor film. This application note can guide you through these considerations. For applications with transients, pulses or surges the following must be considV 2t ered: V E = ––– R 1. Do not exceed the normal rated operating voltage of the device. t 2. Using the figure at right, estimate the E=1 –CV2 energy (Ea) and the pulse duration V 2 (ta) for a single pulse in your applicat = RC tion. t 3. Calculate the energy ratio in percent (Er) between the nominal energy rating of the model you have chosen V2t V E = ––– 3R (see table) and the single pulse energy in your application (Ea from t step 2) using the formula: Ea Er = –––––––– x 100 V2t V E = ––– Enominal 3R 4. Refer to the Pulse Chart. On this t chart find the point where the energy E = Energy (joules) ratio (Er), found at step 3, and time t = Time (seconds) (ta) coincide. Qualify that this point V = Voltage (volts) falls below the maximum pulse R = Resistance (ohms) energy curve. If the point is above C = Capacitance (farads) the curve a bigger model should be chosen. 100 10 1 0.1 1µs 10µs 100µs 1 ms Pulse Width 10 ms 33 Joules 1 Watts 44 Joules 1.5 Watts 100 ms O r d e r i n g i n f o r m at i o n RoHS Compliant TFSA100KJE Series Energy Rating joules A = 6 D = 33 B = 9 E = 44 C = 11 F = 55 Ohm Value Example: 100R = 100Ω 2K40 = 2400Ω Tolerance F = 1% G = 2% J = 5% K = 10% Standard Part Numbers for TFS Series Ohms Tol. 100 100 220 270 470 470 680 750 1,000 1,000 1,500 2,200 2,700 4,700 4,700 4,990 5,000 6,800 10,000 10,000 16,000 20,000 20,000 22,000 27,000 47,000 50,000 51,000 75,000 6 Joules 0.5 Watts 9 Joules 0.5 Watts 11 Joules 0.75 Watts 1% TFSA100RFE 5% TFSB100RJE TFSD100RJE 1% TFSA220RFE 5% TFSA270RJE TFSC270RJE TFSD270RJE 1% TFSA470RFE 55 Joules 2 Watts TFSF100RJE TFSF270RJE 5% TFSB470RJE TFSE470RJE 5% TFSA680RJE TFSC680RJE TFSE680RJE TFSF680RJE 5% TFSB750RJE TFSD750RJE TFSF750RJE 1% TFSA1K00FE 5% TFSA1K00JE TFSB1K00JE TFSC1K00JE TFSD1K00JE TFSE1K00JE TFSF1K00JE 5% TFSA1K50JE TFSC1K50JE TFSD1K50JE TFSF1K50JE 1% TFSA2K20FE 5% TFSB2K70JE TFSE2K70JE 1% TFSA4K70FE 5% TFSA4K70JE TFSC4K70JE TFSD4K70JE 1% TFSA4K99FE 5% TFSA75K0JE 5% TFSB6K80JE TFSE6K80JE 1% TFSA10K0FE 5% TFSA10K0JE TFSB10K0JE TFSC10K0JE TFSD10K0JE TFSF10K0JE 5% TFSF16K0JE 1% TFSA20K0FE TFSF20K0JE 5% TFSB20K0JE TFSD20K0JE 1% TFSA22K0FE 5% TFSA27K0JE TFSC27K0JE TFSE27K0JE 1% TFSA47K0FE 5% TFSA50K0JE TFSF51K0JE 5% TFSB51K0JE TFSC51K0JE TFSD51K0JE 5% TFSE75K0JE 100,000 1% TFSA100KFE 100,000 5% TFSB100KJE TFSC100KJE TFSD100KJE rev 7/19-2 1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com 59 TFSF100KJE