1、7 SPARK IGNITER SEMICONDUCTOR RESISTANCE MEASUREMENT USING CONTROLLED ENERGY LEVELS a SAE reviews each technical report at least every five yean at which time it WE invites your written comments and suggestions. *- Copyright 19 8 5 Society of Automotive Engineers, Inc. All rights resewed. - -_ z -a
2、r - .- - - -*i 5 - - nFe Engineering AEROSPACE INFORMATION Advaming Me$ility$) -A=Rc?swrceFOr REPORT 4Qo OMMONWEALTH DRIVE, WARRENDALE, PA 1M)96 . PURPOSE The purpose of this report is to provide specific information on instrumentation and procedures to measure spark igniter tip semiconduc- tor resi
3、stance at an applied voltage level of 500 to 1000 volts without introducing heating effects. AIR 1921 I ssued March 1985 Revised SCOPE This report describes a method of semiconductor resistance measurement using control led energy levels and a digital processing osci 1 loscope to acquire and process
4、 test data. . 1. INTRODUCTION: 1.1 The technique of resistance measurement descri bed herein al 1 ows measurements to be made at high voltage without producing appreciable localized heating of the sample. The igniter tip semiconductor under test is subjected to a high voltage pulse of controlled ene
5、rgy level, and a digital processing osci 1 loscope is used to monitor the resultant current and vol tage waveforms. The effective resistance is then computed at a specified voltage level. Emperical tests have indicated that at an energy level in the order of three millijoules, the heating effects ha
6、ve no perceptible impact on the resis- tance measurement. These techniques are recommended for use as a laboratory measurement procedure during igniter development rather than as a manufac- turing test procedure. 2. DESCRIPTION OF EQUIPMENT AND TEST PROCEDURE: 2.1 Figure 1.illustrates the test circu
7、it- utilized. A 0.01-uF capacitor is charged through the igniter tip under test and a current shunt each time the mercury relay is energized. Contact is maintained with the semiconductor by means of needle-tipped probes held in a fixture so as to maintain a probe tip spacing of approximately 0.100 i
8、nches. 2,2 A Norland 3001 digital processing oscilloscope or equivalent is used to acquire simultaneous vol tage and current waveforms for the igniter tip under test. The oscilloscope is programmed to locate the specific point on the SA Technical Board Rules provide that: “This report is published b
9、y SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.“ : may be reaffirmed, a- -_ revis
10、ed, or A cancelled. Printed in U.S.A. 2.2 (Continued): vol tage waveform corresponding to 500 volts. The respective current level on the current waveform is then determined, These instantaneous voltage and current levels are used to compute the equivalent resistance. It should be noted that the osci
11、lloscope must be programmed to subtract that portion of the instantaneous voltage which results from including the current shunt in the voltage measurement. Attempts to locate the current shunt in the ground circuit were not successful due to spurious triggering of the oscilloscope. The oscilloscope
12、 is then programmed to accumulate data from five successive tests on the same sample piece and then compute the arithmetic average of the computed resistance measurements. 2.3 Figures 2, 3 and 4 illustrate the displayed data for five successive tests on a representative test sample. 2.4 The labels o
13、n the oscilloscope display correspond to the following quan- ti ties : A = Instantaneous voltage B = Computed resistance C = Summation of resistances measured D = Number of tests completed E = Average resistance for five successive tests PREPARED BY PROPULSION IGNITION SYSTEMS SAE COMMITTEE E-30, w
14、o AWI- dZ 30 -2 PO ou - ua z- mr -x n L O w m O 0-I e um m . O v) + -3- L n f 8 5 v I E o u n W I- - W gx In -0 O 8 e O ou I wz ro u JW v) L XQ nI- J- oz a ow LLr: I- V v) W e 7 w e 3 t3 6 i _-._ - _ SAE AIR*L72L 85 E 83573L10 0007086 O H -4 - 002 us B = 26141. D = 1.0000 A = 501.95 C = 2614.). E =
15、0.0000 - P v = 0.0000 Q V = 1.0156 2048 H=0.0000 US 2606 H= 1.1160 MS FIRST PULSE A = 500.00 C = 52181. E = 0.0000 002 us B = 26039. D = 2.0000 L P v = 0.0000 Q V = 1.0156 2048 H= 0.0000 US 2607 H= 1.1180 MS SECOND PULSE , FIGURE 2 -5- A = 500.00 C = 78220. E = 0,0000 A = 501.95 B = 26141 C = 1.0436
16、E+05 D = 4.0000 E = 0.0000 002 us I3 = 26039. D = 3.0000 - P v= 0.0000 Q v- 1,0156 2048 H- 0.0000 US 2607 H= 1.1180 MS l -# THIRD PULSE FOURTH PULSE P v= 0,0000 v= 1.01561 2048 H0.0000 US I !605 H= 1.1140 h FI GURE 3 : SAE AIR*l92l, 85 8357390 0007088 9 W -6- I A = 500.00 002 us I B = 26039. C = 1.3040E+05 D = 5.0000 E = 26080, I FI FTH PULSE I- ?I P VE 0.000 Q V- 1.0156 2048 H= O. O000 US 2605 H = 1.1140 MS FI GURE 4