l d d type ccr series the ccr series of resistors is constructed utilising solid ceramic composition, which is the traditional medium for absorbing high energy pulses, in cases of high inrush current. these resistors have evolved over many years to have excellent pulse withstand capabili- ties, whilst remaining very stable. these improved characteristics have been achieved by prudent selection of materials of optimum physical properties and by advances in the manufacturing process. the ccr series are ideal for circuitry associated performance in high voltage power supplies, r-c snubber circuits, and inrush limiters. key features designed for pulse withstand range of resistance tolerances solid ceramic composition low cost, high performance two sizes available wide range of resistance values available on tape characteristics - electrical power at 70c ambient: 0.5 watt. 1.0 watt. 2.0 watt. derating: derating to 0 at 200c derating to 0 at 200c derating to 0 at 200c resistance range: 10r C 100k 3r3 C 390k 3r3 C 390k resistance tolerance: 10% e12 series 10% e12 series 10% e12 series temp. coefficient (ppm/c): <100r: -900 to 300 >100r: -1300 to 300 max. working voltage: 200v 300v 400v max. overload voltage: 400v 600v 800v dielectric withstand voltage: 500 volts 500 volts 700 volts impulse withstanding voltage*: 10 kv 14 kv 20 kv nb *: please refer to resistance to pulse circuit dimensions bulk l d d (nom) l ccr1/2 9.0 1.0 3.5 0.5 0.7 30 3 ccr1 16.5 1.0 5.5 1.0 0.8 38 3 ccr2 19.0 1.0 7.0 1.0 0.8 38 3 resistance to pulse circuit resistance to pulse graphs ccr1 ccr2 characteristics - environmental operating temperature range: -40c to +200c temperature cycles (-40c to 85c, 5 cycles): r/r 2% load life (1000 hours at 70c): r/r 5% resistance to solder heat (360c for 3 seconds): r/r 3% short time overload (2x rated voltage for 5 seconds): r/r 2% humidity (40c, 95%rh 240 hrs.): r/r 5% 10k? c=1,000pf dc (max. pulse voltage) sw 1 secon 1 secoff rx 0 100 1,000 10,000 20,000 cycles 0.80 0.60 0.40 0.20 0 r/r (%) 100 ohms 1 kohm 10 kohms dc 20kv 1 sec. on 1 sec. off 0 100 1,000 10,000 20,000 cycles 0.80 0.60 0.40 0.20 0 r/r (%) 100 ohms 1 kohm 10 kohms dc 14kv 1 sec. on 1 sec. off ceramic composition resistors type ccr series literature no. 1773193 issued: 12-08 dimensions are shown for reference purposes only. dimensions are in millimetres unless otherwise specified. specifications subject to change. tycoelectronics.com passives.tycoelectronics.com
application notes limitations of potential pulsing on fixed ceramic composition resistors ceramic composition resistors are susceptible to failure under some high voltage conditions. in circuitry where there is a possibility of transient potentials, considerable high voltage may be applied to a resistor for a short period of time. these notes are intended to aid the determining of safe potential level for the ccr series when used in pulse application. for pulse power limitations please refer to the graph (fig.1). power below that specified on the graph will, generally not cause any significant degradation to the resistor, but please note that the resistance value may vary slightly due to repeated pulsing over a long period of time. the circuit designer should also be aware of the fact that the pulse voltage is limited even under the conditions on which the graph is based. the maximum peak pulse voltage for these resistors is the lesser of (a) or (b) below. (a) (b) v peak = po x r ccr1/2 800v ccr1 1200v where: ccr2 1600v po is the pulse limit power taken from the graph. r is the resistance value in ohms. the peak power is defined as the maximum power dissipated at any point in time regardless of the waveform shape. the pulse waveform, if other than square wave, must first be converted to an approximate square wave as shown below. wp - peak power. wo - rated power. t - time to attenuate down to the rated power. wp - peak power. wo - rated power. t - time to attenuate down to the rated power. application notes the following design rules determine if derating of the pulse limit power (po) obtained from the graph is required for repetitive pulse applications. 1. if t off < 4 seconds, or t off < 5m seconds and (t off/t) < 1, then the peak power is treated as continuous power and, therefore, pm = the resistors rated wattage. 2. if t off is > 4 sec, but is < 100 sec, and (t off/t) < 700, then pm = po x 0.01 x (t off/t)0.7. 3. if t off is > 100 sec, and (t off/t) < 200, then pm = po x 0.01 x (t off/t)0.85. 4. if t off is > 4 sec, but is < 100 sec, and (t off/t) < 700, or t off is >100 sec, and (t off/t) > 200, then pm = po as obtained from the pulse power graph. where: pm: derated pulse power (w) po: pulse power from graph below (w) t off: off time between pulses (sec) t: pulse width (sec) ceramic composition resistors type ccr series literature no. 1773193 issued: 12-08 dimensions are shown for reference purposes only. dimensions are in millimetres unless otherwise specified. specifications subject to change. tycoelectronics.com passives.tycoelectronics.com
pulse limiting power (po) one pulse 0.0001 0.001 0.01 0.1 1 10 pulse t ime (s) 1000000 100000 10000 1000 100 10 1 ccr 2 ccr 1 ccr 1/2 pulse power how to order ccr 1 10r k b common part _ - 0.5 watt 1 C 1.0 watt 2 C 2.0 watt power rating 10 ohm (10 ohms) 10r 1k ohms (1000 ohms) 1k0 100k ohms (100000 ohms) 100k resistance value tolerance ccr k - 10% packaging b - bulk t - taped application notes (continued) notes ? graph pulse power (po) is for ambient temperatures of 70c or less. for ambient operating temperatures greater than 70c, pulse power (po) or (pm) must be further derated by 1.18% per c above 70c in accordance with the power derating schedule of the resistor. ? if derated pulse power (pm) is calculated to be less than the resistors rated continuous power, the resistors rated wattage should be used. ceramic composition resistors type ccr series literature no. 1773193 issued: 12-08 dimensions are shown for reference purposes only. dimensions are in millimetres unless otherwise specified. specifications subject to change. tycoelectronics.com passives.tycoelectronics.com
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